日期:2014-05-17  浏览次数:20944 次

小虾请教一个问题,关于ajax和servlet交互的问题~~~
html:
HTML code

<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'index_1.jsp' starting page</title>
    
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->

  </head>
  <script type="text/javascript">
    //定义变量xmlHttp
    var xmlHttp;
    //定义函数,用来为xmlHttp赋值
    function createXMLHttpRequest(){                        
        if(window.ActiveXObject){                        
        xmlHttp= new ActiveXObject("Microsoft.XMLHTTP");                    
        }else if(window.XMLHttpRequest){                        
        xmlHttp=new XMLHttpRequest();                    
    }    
    }    
    //定义函数,向服务器发送信息                
    function sendMessage(){                        
        createXMLHttpRequest();    
        //处理缓存问题        
        
        xmlHttp.open("GET","http://localhost:80/ajax_0/servlet/Servlet_1?time="+new Date().getDay(),true);    
        xmlHttp.send(null);                    
    }                        

    
  
  </script>
  <body>
  <b>利用JavaScript的事件处理机制,通过XMLHttpRequest对象执行服务器端的程序</b><br><br><br>
  
  1、onMouseOver事件
  <a href="#" onMouseOver="sendMessage()">哈哈</a>
  <br><br><br>
  2、onClick事件
  <input type="button" value="按钮" onClick="sendMessage()" />
  <br><br><br>
  3、onBlur事件
  <input type="text" name="user" onBlur="sendMessage()"/>
  <br><br><br>
  4、onChange事件
  <input type="text" name="user" value="tianyitime" onChange="sendMessage()"/>
  <br><br><br>
  <a href="index.jsp">返回</a>
  </body>
</html>




servlet:
Java code

package com.tianyitime.ajax;

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 Servlet_1 extends HttpServlet {

    /**
     * Constructor of the object.
     */
    public Servlet_1() {
        super();
    }

    /**
     * Destruction of the servlet. <br>
     */
    public void destroy() {
        super.destroy(); // Just puts "destroy" string in log
        // Put your code here
    }

    /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method