package ajax.servlet;  

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;  

/**

 * Ajax例子后台处理程序

 * @author bing

 * @version 2011-07-07

 *

 */

public class TestAjaxServlet extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {  

        response.setContentType("text/html;charset=utf-8");

        PrintWriter out = response.getWriter();  

        String name = request.getParameter("name");

        String age = request.getParameter("age");  

        System.out.println("{\"name\":\"" + name + "\",\"age\":\"" + age + "\"}");

        out.print("{\"name\":\"" + name + "\",\"age\":" + age + "}");  

        out.flush();

        out.close();

    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {  

        doGet(request,response);

    }  

}
 

<div id="show">显示区域</div>

<div id="parameters">

    name:<input id="name" name="name" type="text" /><br />

    age:<input id="age" name="age" type="text" /><br />

</div>  

<script type="text/javascript" src="prototype.js"></script>

    <script type="text/javascript">

        function prototypeAjax()

        {

        var url = "servlet/testAjax";//请求URL

        var params = Form.serialize("parameters");//提交的表单

      var myAjax = new Ajax.Request(  

        url,{

            method:"post",// 请求方式

            parameters:params, // 参数

            onComplete:pressResponse, // 响应函数

            asynchronous:true

        });

        $("show").innerHTML = "正在处理中...";

        }

        function pressResponse(request)

        {

        var obj = request.responseText; // 以文本方式接收

        $("show").innerHTML = obj;

        var objJson = request.responseText.evalJSON(); // 将接收的文本用解析成Json格式

        $("show").innerHTML += "name=" + objJson['name'] + " age=" + objJson['age'];  

        }

</script>

<input id="submit" type="button" value="提交" onclick="prototypeAjax()" /><br />  

<script type="text/javascript" src="jquery-1.3.2.min.js"></script>

<script type="text/javascript" src="json2.js"></script>

<input id="submit" type="button" value="提交" /><br />

<script type="text/javascript">

        function jqueryAjax()

        {

            var user={"name":"","age":""};

            user.name= $("#name").val();

            user.age=$("#age").val();

            var time = new Date();

            $.ajax({

                 url: "servlet/testAjax?time="+time,

                 data: "name="+user.name+"&age="+user.age,

                 datatype: "json",//请求页面返回的数据类型

                 type: "GET",

                 contentType: "application/json",//注意请求页面的contentType 要于此处保持一致

                 success:function(data) {//这里的data是由请求页面返回的数据

                 var dataJson = JSON.parse(data); // 使用json2.js中的parse方法将data转换成json格式

                 $("#show").html("data=" + data + " name="+dataJson.name+"  age=" + dataJson.age);

                 },

                 error: function(XMLHttpRequest, textStatus, errorThrown) {

                   $("#show").html("error");

                 }

           });

        }

       $("#submit").bind("click",jqueryAjax); // 绑定提交按钮

 </script>  

<script type="text/javascript">

        var xmlhttp;

        function XMLHttpRequestAjax()

        {

            // 获取数据

         var name = document.getElementById("name").value;

             var age = document.getElementById("age").value;

         // 获取XMLHttpRequest对象

         if(window.XMLHttpRequest){

            xmlhttp = new XMLHttpRequest();

         }else if(window.ActiveXObject){

            var activxName = ["MSXML2.XMLHTTP","Microsoft.XMLHTTP"];

            for(var i =  ; i < activexName.length; i++){

               try{

                   xmlhttp = new ActiveXObject(activexName[i]);

                   break;

               }catch(e){}

            }

         }

             xmlhttp.onreadystatechange = callback;  //回调函数

             var time = new Date();// 在url后加上时间，使得每次请求不一样

             var url = "servlet/testAjax?name="+name+"&age="+age+"&time="+time;

             xmlhttp.open("GET",url,true); // 以get方式发送请求

             xmlhttp.send(null);   // 参数已在url中，所以此处不需要参送

        }

        function callback(){

           if(xmlhttp.readyState == ){

              if(xmlhttp.status == ){ // 响应成功

                  var responseText = xmlhttp.responseText;   // 以文本方式接收响应信息

                  var userdiv = document.getElementById("show");

                  var responseTextJson = JSON.parse(responseText); // 使用json2.js中的parse方法将data转换成json格式

                  userdiv.innerHTML=responseText + " name=" + responseTextJson.name + " age=" + responseTextJson.age;

              }

           }

        }

</script>

<input id="submit" type="button" value="提交" onclick="XMLHttpRequestAjax()" /><br />