【Java】生成图形验证码

昵称67046736 2020-07-30

展开全文

生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML 4.01 Transitional//EN"

"http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML 4.01 Transitional//EN"

"http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"

"http://www.www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>-instance" xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>-instance" xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>

生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML 4.01 Transitional//EN"

"http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML 4.01 Transitional//EN"

"http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"

"http://www.www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>-instance" xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>-instance" xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>

生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML 4.01 Transitional//EN"

"http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML 4.01 Transitional//EN"

"http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"

"http://www.www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>-instance" xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://生成验证码工具类

package com.util;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.awt.geom.AffineTransform;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtils {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，

去掉了1,0,i,o几个容易混淆的字符

public static final String VERIFY_CODES =

"23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

private static Random random = new Random();

/**

* 使用系统默认字符源生成验证码

* @param verifySize 验证码长度

* @return

public static String generateVerifyCode(int verifySize){

return generateVerifyCode(verifySize, VERIFY_CODES);

}

/**

* 使用指定源生成验证码

* @param verifySize 验证码长度

* @param sources 验证码字符源

* @return

public static String generateVerifyCode(int verifySize, String

sources){

if(sources == null || sources.length() == 0){

sources = VERIFY_CODES;

}

int codesLen = sources.length();

Random rand = new Random(System.currentTimeMillis());

StringBuilder verifyCode = new StringBuilder(verifySize);

for(int i = 0; i < verifySize; i++){

verifyCode.append(sources.charAt(rand.nextInt(codesLen-

1)));

}

return verifyCode.toString();

}

/**

* 生成随机验证码文件,并返回验证码值

* @param w

* @param h

* @param outputFile

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, File

outputFile, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, outputFile, verifyCode);

return verifyCode;

}

/**

* 输出随机验证码图片流,并返回验证码值

* @param w

* @param h

* @param os

* @param verifySize

* @return

* @throws IOException

public static String outputVerifyImage(int w, int h, OutputStream

os, int verifySize) throws IOException{

String verifyCode = generateVerifyCode(verifySize);

outputImage(w, h, os, verifyCode);

return verifyCode;

}

/**

* 生成指定验证码图像文件

* @param w

* @param h

* @param outputFile

* @param code

* @throws IOException

public static void outputImage(int w, int h, File outputFile,

String code) throws IOException{

if(outputFile == null){

return;

}

File dir = outputFile.getParentFile();

if(!dir.exists()){

dir.mkdirs();

}

try{

outputFile.createNewFile();

FileOutputStream fos = new FileOutputStream(outputFile);

outputImage(w, h, fos, code);

fos.close();

} catch(IOException e){

throw e;

}

/**

* 输出指定验证码图片流

* @param w

* @param h

* @param os

* @param code

* @throws IOException

public static void outputImage(int w, int h, OutputStream os,

String code) throws IOException{

int verifySize = code.length();

BufferedImage image = new BufferedImage(w, h,

BufferedImage.TYPE_INT_RGB);

Random rand = new Random();

Graphics2D g2 = image.createGraphics();

g2.setRenderingHint

(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

Color[] colors = new Color[5];

Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,

Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA,

Color.ORANGE,

Color.PINK, Color.YELLOW };

float[] fractions = new float[colors.length];

for(int i = 0; i < colors.length; i++){

colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];

fractions[i] = rand.nextFloat();

}

Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色

g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);

g2.setColor(c);// 设置背景色

g2.fillRect(0, 2, w, h-4);

//绘制干扰线

Random random = new Random();

g2.setColor(getRandColor(160, 200));// 设置线条的颜色

for (int i = 0; i < 20; i++) {

int x = random.nextInt(w - 1);

int y = random.nextInt(h - 1);

int xl = random.nextInt(6) + 1;

int yl = random.nextInt(12) + 1;

g2.drawLine(x, y, x + xl + 40, y + yl + 20);

}

// 添加噪点

float yawpRate = 0.05f;// 噪声率

int area = (int) (yawpRate * w * h);

for (int i = 0; i < area; i++) {

int x = random.nextInt(w);

int y = random.nextInt(h);

int rgb = getRandomIntColor();

image.setRGB(x, y, rgb);

}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));

int fontSize = h-4;

Font font = new Font("Algerian", Font.ITALIC, fontSize);

g2.setFont(font);

char[] chars = code.toCharArray();

for(int i = 0; i < verifySize; i++){

AffineTransform affine = new AffineTransform();

affine.setToRotation(Math.PI / 4 * rand.nextDouble() *

(rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2,

h/2);

g2.setTransform(affine);

g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5,

h/2 + fontSize/2 - 10);

}

g2.dispose();

ImageIO.write(image, "png", os);

}

private static Color getRandColor(int fc, int bc) {

if (fc > 255)

fc = 255;

if (bc > 255)

bc = 255;

int r = fc + random.nextInt(bc - fc);

int g = fc + random.nextInt(bc - fc);

int b = fc + random.nextInt(bc - fc);

return new Color(r, g, b);

}

private static int getRandomIntColor() {

int[] rgb = getRandomRgb();

int color = 0;

for (int c : rgb) {

color = color << 8;

color = color | c;

}

return color;

}

private static int[] getRandomRgb() {

int[] rgb = new int[3];

for (int i = 0; i < 3; i++) {

rgb[i] = random.nextInt(255);

}

return rgb;

}

private static void shear(Graphics g, int w1, int h1, Color color)

{

shearX(g, w1, h1, color);

shearY(g, w1, h1, color);

}

private static void shearX(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(2);

boolean borderGap = true;

int frames = 1;

int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(0, i, w1, 1, (int) d, 0);

if (borderGap) {

g.setColor(color);

g.drawLine((int) d, i, 0, i);

g.drawLine((int) d + w1, i, w1, i);

}

private static void shearY(Graphics g, int w1, int h1, Color

color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;

int frames = 20;

int phase = 7;

for (int i = 0; i < w1; i++) {

double d = (double) (period >> 1)

* Math.sin((double) i / (double) period

+ (6.2831853071795862D * (double) phase)

/ (double) frames);

g.copyArea(i, 0, 1, h1, 0, (int) d);

if (borderGap) {

g.setColor(color);

g.drawLine(i, (int) d, i, 0);

g.drawLine(i, (int) d + h1, i, h1);

}

public static void main(String[] args) throws IOException{

File dir = new File("C:/Users/H__D/Desktop/");

int w = 200, h = 80;

String verifyCode = generateVerifyCode(4);

File file = new File(dir, verifyCode + ".jpg");

outputImage(w, h, file, verifyCode);

}

使用图形验证码

1、使用流程

技术图片

2、服务器端生成验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class CreateCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

resp.setHeader("Pragma", "No-cache");

resp.setHeader("Cache-Control", "no-cache");

resp.setDateHeader("Expires", 0);

resp.setContentType("image/jpeg");

//生成随机字串

String verifyCode = VerifyCodeUtils.generateVerifyCode(4);

//存入会话session

req.getSession().setAttribute("CODE", verifyCode.toLowerCase

());

//生成图片

int width = 100;//宽

int height = 40;//高

VerifyCodeUtils.outputImage(width, height,

resp.getOutputStream(), verifyCode);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

doGet(req, resp);

}

3、服务器端验证验证码servlet

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.util.VerifyCodeUtils;

public class VerifyCodeServlet extends HttpServlet {

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

String code = req.getParameter("code");

String key = (String) req.getSession().getAttribute("CODE");

if(code != null && code.equalsIgnoreCase(key)){

req.getSession().removeAttribute("CODE");

resp.getWriter().println(true);

}else{

resp.getWriter().println(false);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse

resp) throws ServletException, IOException {

// TODO Auto-generated method stub

super.doGet(req, resp);

}

4、servet的注册，web.xml文件

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.-instance"

xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>-instance" xmlns="http://java./xml/ns/javaee"

xsi:schemaLocation="http://java./xml/ns/javaee

http://java./xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"

version="3.0">

<display-name>test-captcha</display-name>

<servlet-name>CreateCodeServlet</servlet-name>

<servlet-class>com.servlet.CreateCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>CreateCodeServlet</servlet-name>

<url-pattern>/createCode</url-pattern>

</servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<servlet-class>com.servlet.VerifyCodeServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>VerifyCodeServlet</servlet-name>

<url-pattern>/verifyCode</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

5、前端html文件

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//深圳市博纳网络信息技术有限公司//DTD HTML

4.01 Transitional//EN" "http://www.">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<h2>测试验证码：</h2>

请输入验证码：<input type="text" name="code" /><img id="codeimg"

src="${pageContext.request.contextPath }/createCode"

onclick="changeImg()"><a href="javascript:void(0);"

onclick="changeImg()">看不清，换一张</a>

//改变验证码事件

function changeImg(){

var img = document.getElementById(‘codeimg‘);

img.src = "${pageContext.request.contextPath

}/createCode?x=" + Math.floor(Math.random()*100)

}

//提交验证并验证验证码

function submit(){

var input = document.getElementsByTagName(‘input‘)[0];

//ajax提交

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function(){

if(xhr.readyState == 4 && xhr.status == 200) {

alert(xhr.responseText);

}

xhr.open(‘get‘,‘${pageContext.request.contextPath

}/verifyCode?code=‘ + input.value);

xhr.send(null);

}

</script>

</body>

</html>

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