和asp.net里面没有什么区别啦：
jsp
<%@ page language="java" contentType="text/html" pageEncoding="utf-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="content" content="text/html;charset=utf-8">
<script type="text/javascript" src="jquery-1.3.2.js"></script>
<script type="text/javascript">
function sub()
{
$.ajax({
type:"post",
url:"loginServlet",
data:{
username:$("#username").val(),
content:$("#content").val()
},
success:function(data,textStatus){
$("#resText").html(data);
}
});
}
</script>
</head>
<body>
<form action="./test" id="form1" method="post">
<p></p>
<p><input type="text" name="username" id="username"/></p>
<p><textarea name="content" id="content" rows="2" cols="20"></textarea></p>
<p><input type="button" id="send" value="" onclick="sub();"/></p>
</form>
<div class="comment">
</div>
<div id="resText">
</div>
</body>
</html>
Servlet
package com;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class test extends HttpServlet {
public void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
System.out.println("start............");
String username=request.getParameter("username");
String content=request.getParameter("content");
//username=new String(username.getBytes("gb2312"),"utf-8");
PrintWriter out = response.getWriter();
out.write(username);
System.out.println("username>>=="+username);
out.write(content);
out.flush();
out.close();
System.out.println("end");
}
}