ajax的简单应用

今天初学ajax，感觉ajax真是一门好技术，所以就感觉得要学好它

先写一个简单的例子吧

首先创建一个jsp吧，ajax.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>


  
     
    
    
    
       
    
    
    
                                                                    
    
  
  
    

    

    

  

然后再创建一个进行异步处理的servlet AjaxServlet.servlet

此servlet处理ajax.jsp 然后返回数据

/**
 * author botao
 * 功能:用来测试ajax的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;
public class AjaxServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException
    {
        System.out.println("doGet invoked");
        process(req, resp);
    }
    private void process(HttpServletRequest req, HttpServletResponse resp)
            throws IOException
    {
        String v1 = req.getParameter("v1");
        String v2 = req.getParameter("v2");
        System.out.println("v1=" + v1 + ", v2=" + v2);
                 
        String v3 = String.valueOf(Integer.valueOf(v1) + Integer.valueOf(v2));
        PrintWriter out = resp.getWriter();
        // try
        // {
        // Thread.sleep(5000);
        // }
        // catch (InterruptedException e)
        // {
        // e.printStackTrace();
        // }
        resp.setHeader("pragma", "no-cache");
        resp.setHeader("cache-control", "no-cache");
        out.println(v3);
        out.flush();
    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException
    {
        System.out.println("doPost invoked");
        this.process(req, resp);
    }
}

这样，一个简单的ajax异步刷新就完成了