1.java程序:
package com.eduask;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//编写一个时间日期函数，当用户点击显示时间按钮，服务器会自动显示当前系统时间;
public class Demo1 extends HttpServlet {
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setCharacterEncoding("utf-8");
resp.setContentType("text/html;charset=utf-8");
Date date=new Date();
PrintWriter out =resp.getWriter();
out.print("当前系统时间是："+date);
}
}
2.date.jsp文件
<input id="input1"type="button" value="获得系统时间" οnclick="getXhr()" >
<script type="text/javascript">
var input1=document.getElementById("input1");
input1.οnclick=function(){
var xhr=getXhr();
xhr.onreadystatechange=function(){
if(xhr.readyState==4){
if(xhr.status==200){
var msg=xhr.responseText;
document.write(msg);
}
}
};
xhr.open("get","/ajax/Demo1",true);
xhr.send(null);
};
function getXhr(){
var xhr;
if(window.XMLHttpRequest){
xhr=new XMLHttpRequest();
}else{
xhr=new ActiveXObject("microsoft.xmlhttp");
}
return xhr;
}
</script>
3.web.xml配置文件
<servlet>
<servlet-name>Demo1</servlet-name>
<servlet-class>com.eduask.Demo1</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Demo1</servlet-name>
<url-pattern>/Demo1</url-pattern>
</servlet-mapping>
