下面是别人总结的很全面
http://www./yzzh9/archive/2009/06/09/280908.html
http://www./course/4_webprogram/jsp/jsp_js/200863/121115.html#
下面是自己总结的：代码可以运行的。可以运行下看看，加深理解。
1、登录jsp页面
<%@ page language="java" contentType="text/html"
pageEncoding="utf-8"%>
<html>
<head>
<title>this first jsp and Servlet</title>
</head>
<body>
<form action="tpath" method="post">
名字：<input type="text" name="uname">
密码：<input type="text" name="password"><br>
<input type="submit" value="提交">
</form>
</body>
</html>
2、servlet类的写法
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class TestTZ extends HttpServlet{
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// TODO Auto-generated method stub
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
String path2="/testPath.jsp";
String path3="testPath.jsp";
String uname=req.getParameter("uname");
String password=req.getParameter("password");
req.setAttribute("k", uname);
req.setAttribute("v", password);
// this.getServletConfig().getServletContext().getRequestDispatcher(path2).forward(req, resp);
// req.getRequestDispatcher(path3).forward(req, resp);
// 上面两个forward方法都可以，跳转到另外一个页面（他们是服务器端跳转）。IE里面的地址看不出跳转到那个jsp页面。
//但是上面的两个跳转的具体区别，还有点不太清楚。
//============================================================
//sendRedirect它是客户端跳转，可以在IE里面看到，跳转到那个jsp页面。
//但是它不能通过request.getAttribute("变量");得到值。
resp.sendRedirect(path3);
}
}
3、接受值的jsp的写法
<%@ page language="java" contentType="text/html"
pageEncoding="utf-8"%>
<html>
<head>
<title>Insert title here</title>
</head>
<body>
结果是：<br>
<%=request.getAttribute("k") %><br>
<%=request.getAttribute("v") %>
</body>
</html>
4、servlet的配置文件web.xml的写法
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
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">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>jack3</servlet-name>
<servlet-class>org.tiaozhuan.com.TestTZ</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>jack3</servlet-name>
<url-pattern>/tpath</url-pattern>
</servlet-mapping>
</web-app>
