Java中：struts2+jQuery+ajax调用演示

收云轩 2017-04-06

展开全文

环境：

操作系统：Windows 7

应用程序服务器：apache-tomcat-7.0.11

开发工具：IntelliJ IDEA 11.1.1

Java版本：Java(TM) SE Runtime Environment (build 1.7.0_03-b05)

Struts版本：struts-2.2.1.1

jQuery版本：1.7.2

MySql版本： 5.5.16 MySQL Community Server (GPL)

mysql-connector-java：5.1.15

2013年4月16日注:本例中采用的JSON数据格式,推荐使用性能更好的jackson进行序列化,不要使用json-lib

关键点：

1.引入包：struts2对数据进行json序列化，必须要用到struts2的json-lib，struts2-json-plugin包；

2.json数据处理：异步提交的数据采用json格式，struts2-json-plugin会对数据进行json处理，所以struts2配置文件struts.xml中的package节点的extends必须是：extends="json-default"；

例如：<package name="default" namespace="/test" extends="json-default">

3.同样的由于返回的是json数据，所以result的类型也必须采用json；

注意：struts2只能在引入json-lib，struts2-json-plugin包时，result的type属性设定json才不会报错：<result name="userInfo" type="json"></result>

4.针对异步提交，action的result节点值应该为空，即不能再转向(例如：只能为<result name="userInfo" type="json"></result>)；

时序：

绿色代表客户端请求；紫色代表从数据库返回到客户端。

jsp-----(表单提交)---->jQuery------(ajax异步)----->Struts2-----(action取得json数据)----->调用service------->其它(spring，hibernate等)-----(model)----->DB

DB----(model)------>hibernate,spring--------->service-------Struts2(action,result)------->jQuery(ajax)---------->jsp

代码：

1. 入口jsp：input_user.jsp

<%--
  Created by IntelliJ IDEA.
  User: Anyx
  Date: 12-4-15
  Time: 下午3:46
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title></title>
    <script type="text/javascript" src="/js/jquery-1.7.2.js"></script>
    <script type="text/javascript" src="/js/myJs.js"></script>
</head>
<body>
    <div>
        请输入用户：
    </div>
    <div>
        <form id="subUserForm">
        <input type="text" name="userInfo.id" id="id"/>
        <input type="text" name="userInfo.name" id="name"/>
        </form>
    </div>
    <div>
        <input id="addUser" type="button" value="添加"/>
         <input id="users" type="button" value="所有用户"/>
         <a href="/test/load_allUser_jump.action">所有用户：非异步方式</a>
         <input id="msg" type="button" value="hello"/>
         <input id="msgUserInfo" type="button" value="userInfo"/>
         <input id="msgUserInfoList" type="button" value="userInfoList"/>
    </div>
<div id="allUser">
input_user:
</div>
</body>
</html>

2. jQuery文件：myJs.js

$(document).ready(function () {
    $("#msg").click(function () {
        $.ajax({
            url:'/test/input_user!queryHello',
            type:'POST',
            data:"{}",
            dataType:'json',
            success:function (data) {
                $("#allUser").append("输出了：id:" + data.hello);
            }
        });
        /*$.getJSON("/test/input_user!queryHello", function (data) {
         //通过.操作符可以从data.hello中获得Action中hello的值
         $("#allUser").html("输出了: " + data.hello);
         });*/
    });

    $("#msgUserInfo").click(function () {
        $.ajax({
            url:'/test/userInfo!loadUserInfo',
            type:'post',
            data:"{}",
            dataType:'json',
            success:function (data) {
                $("#allUser").append("<div>输出了：id:" + data.userInfo.id + ", name: " + data.userInfo.name + "</div>");
            }
        });
    });

    $("#msgUserInfoList").click(function () {
        $.ajax({
            url:'/test/userInfoList.action',
            type:'post',
            data:"{}",
            dataType:'json',
            success:function (data) {
                /*$.each(data.userList, function(i, value){
                 $("#allUser").append("<div>输出了：id:"+value.id+", name: "+value.name+"</div>");
                 });*/
                $(data.userList).each(function (i, value) {
                    $("#allUser").append("<div>输出了：id:" + value.id + ", name: " + value.name + "</div>");
                });

            }
        });
    });

    $("#addUser").click(function () {
        //必须先对提交表单数据数据进行序列化，采用jQuery的serialize()方法
        var params = $("#subUserForm").serialize();
        $.ajax({
            url:'/test/add_user.action',
            type:'post',
            data:params,
            dataType:'json',
            success:function (data) {
                /*$.each(data.userList, function(i, value){
                 $("#allUser").append("<div>输出了：id:"+value.id+", name: "+value.name+"</div>");
                 });*/
                $(data.userList).each(function (i, value) {
                    $("#allUser").append("<div>输出了：id:" + value.id + ", name: " + value.name + "</div>");
                });

            }
        });
    });

    $("#users").click(function () {
        $.ajax({
            url:'/test/load_allUser.action',
            type:'post',
            data:"{}",
            dataType:'json',
            success:function (data) {
                /*$.each(data.userList, function (i, value) {
                 $("#allUser").append("<div>输出了：id:" + value.id + ", name: " + value.name + "</div>");
                 });*/
                $(data.userList).each(function (i, value) {
                    $("#allUser").append("<div>输出了：id:" + value.id + ", name: " + value.name + "</div>");
                });

            }
        });
    });
});

3.action类：UserAction.java

public class UserAction extends ActionSupport {

    UserService us = new UserService();

    public String inputUser() {
        return "INPUT_USER";
    }

    public String queryHello() {
        this.hello = "hello world";
        return "hel";
    }

    public String loadUserInfo() {
        userInfo = new UserInfo();
        userInfo.setId(3);
        userInfo.setName("取得userInfo");
        return "userInfo";
    }

    public String loadUserInfoList() {
        userList = new ArrayList<UserInfo>();

        UserInfo u1 = new UserInfo();
        u1.setId(1);
        u1.setName("取得userInfo1");

        UserInfo u2 = new UserInfo();
        u2.setId(2);
        u2.setName("取得userInfo2");

        UserInfo u3 = new UserInfo();
        u3.setId(3);
        u3.setName("取得userInfo3");

        userList.add(u1);
        userList.add(u2);
        userList.add(u3);
        return "userInfoList";
    }


    public String addUser() {
        /*userInfo = new UserInfo();
        userInfo.setId(7);
        userInfo.setName("张7");*/

        //如果是异步提交json格式，必须先在js中对提交的表单form进行序列化
        //var params = $("subUserForm").serialize();
        us.addUser(userInfo);

        userList = us.getUser();
        return "ADD_SUCCESS";
    }

    public String loadAllUser() {

        userList = us.getUser();

        return "USER";
    }

    /////////////////
    private String hello;

    public String getHello() {
        return hello;
    }

    public void setHello(String hello) {
        this.hello = hello;
    }

    public List<UserInfo> getUserList() {
        return userList;
    }

    public void setUserList(List<UserInfo> userList) {
        this.userList = userList;
    }

    public UserInfo getUserInfo() {
        return userInfo;
    }

    public void setUserInfo(UserInfo userInfo) {
        this.userInfo = userInfo;
    }

    private UserInfo userInfo;
    private List<UserInfo> userList;
}

4.Struts配置文件：struts.xml

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

<!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
        "http://struts./dtds/struts-2.1.7.dtd">

<struts>
    <!--struts2的开发模式-->
    <constant name="struts.devMode" value="true"/>

    <!--采用json数据格式，package的extends必须是extends="json-default"-->
    <!--并且必须要用到struts2的json-lib，struts2-json-plugin包-->
    <!--采用异步提交方式，result的type="json"，并且result节点值为空-->
    <package name="default" namespace="/test" extends="json-default">
        <!--客户端请求采用DMI（动态调用）-->
        <action name="input_user" class="com.agcro.jquery.action.UserAction">
            <result name="INPUT_USER">/input_user.jsp</result>
            <result name="hel" type="json"></result>
        </action>

        <!--客户端请求（非动态调用）-->
        <action name="userInfo" class="com.agcro.jquery.action.UserAction" method="loadUserInfo">
            <result name="userInfo" type="json"></result>
        </action>

        <action name="userInfoList" class="com.agcro.jquery.action.UserAction" method="loadUserInfoList">
            <result name="userInfoList" type="json"></result>
        </action>


        <action name="add_user" class="com.agcro.jquery.action.UserAction" method="addUser">
            <result name="ADD_SUCCESS" type="json"></result>
        </action>

        <action name="load_allUser" class="com.agcro.jquery.action.UserAction" method="loadAllUser">
            <result name="USER" type="json"></result>
        </action>

        <!--不采用异步提交方式显示-->
        <action name="load_allUser_jump" class="com.agcro.jquery.action.UserAction" method="loadAllUser">
            <result name="USER">/user.jsp</result>
        </action>

    </package>
</struts>

5.Service类：UserService.java

public class UserService {

    public List<UserInfo> getUser(){
        Connection conn=Db.createConnection();
        String sql="select * from user";

        UserInfo userInfo =null;
        List<UserInfo> users =new ArrayList<UserInfo>();
        try{
            PreparedStatement ps=Db.prepare(conn, sql);
            ResultSet rs= ps.executeQuery();
            while(rs.next()){
                userInfo = new UserInfo();
                userInfo.setId(rs.getInt("id"));
                userInfo.setName(rs.getString("name"));
                users.add(userInfo);
            }
            Db.close(rs);
            Db.close(ps);
            Db.close(conn);
        }catch (Exception e){
            e.printStackTrace();
        }
        return users;
    }

    public void addUser(UserInfo userInfo){
        Connection conn=Db.createConnection();
        String sql="insert into user (id, name) values(?,?)";

        try{
            PreparedStatement ps=Db.prepare(conn, sql);
            ps.setInt(1, userInfo.getId());
            ps.setString(2, userInfo.getName());
            ps.executeUpdate();

            Db.close(ps);
            Db.close(conn);
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

6.采用非异步提交后转向的jsp：user.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib uri="/struts-tags" prefix="s" %>
<html>
<head>
    <title></title>
</head>
<body>
    <div id="u">
        <s:iterator value="userList" var="c">
        	<s:property value="#c.id"/> |
        	<s:property value="#c.name"/> |
        	</br>
        </s:iterator>
    </div>

</body>
</html>

7.每个人都知道的应用程序配置文件：web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java./xml/ns/javaee"
           xmlns:xsi="http://www./2001/XMLSchema-instance"
           xsi:schemaLocation="http://java./xml/ns/javaee
		  http://java./xml/ns/javaee/web-app_2_5.xsd"
           version="2.5">

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

    <filter>
        <filter-name>struts2</filter-name>
        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>struts2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

8.访问数据库类：Db.java

package com.agcro.jquery.util;
import java.sql.*;
/**
 * Created by IntelliJ IDEA.
 * UserInfo: Anyx
 * Date: 12-4-15
 * Time: 下午4:44
 * To change this template use File | Settings | File Templates.
 */
public class Db {
    public static Connection createConnection(){
        Connection conn=null;
        String url="jdbc:mysql://localhost/test";
        String username="root";
        String password="123";

        try{
            Class.forName("com.mysql.jdbc.Driver");
            conn= DriverManager.getConnection(url, username, password);
        }catch (Exception e){
            e.printStackTrace();
        }
        return conn;
    }

    public static PreparedStatement prepare(Connection conn, String sql){
        PreparedStatement ps=null;

        try{
            ps=conn.prepareStatement(sql);
        }catch (Exception e){
            e.printStackTrace();
        }
        return ps;
    }

    public static void close(Connection conn){
        if(conn == null){
            return;
        }
        try{
            conn.close();
            conn=null;
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    public static void close(PreparedStatement ps){
        try{
            ps.close();
            ps=null;
        }catch(Exception e){
            e.printStackTrace();
        }
    }

    public  static void close(ResultSet rs){
        try{
            rs.close();
            rs=null;
        }catch (Exception e){
            e.printStackTrace();
        }
    }

}

我的工程结构：