jquery的ajax向后台servlet传递json类型的多维数组

后台运行结果： 前台运行结果：

first.jsp:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>   
    <script type="text/javascript" src="jQuery/jquery-1.9.1.min.js"></script>
    <script type="text/javascript">  
       function test2(){  
       
          //用这种方式组装的json数组是正确的  
          var testArray = new Array();
          for(var i = 0; i < 5; i++) {
              var tempArray = new Array();  
              for(var j = 0; j < 10; j++){
                tempArray.push(i*j);
              }
              testArray.push(tempArray);
          }
          alert("tempArray=" + tempArray);
          
          //用这种方式组装的json数组是正确的
          var jsonArr = new Array();             
          for ( var j = 0; j < 3; j++) {                 
            var jsonObj = {};                  
            jsonObj["gradeId"]=1;                 
            jsonObj["gradeName"]=2;                 
            jsonObj["level"]=3;                 
            jsonObj["boundary"]=4;                 
            jsonObj["status"]=5;                 
            jsonArr.push(jsonObj)             
          }
          alert("jsonArr=" + jsonArr);            
          
          // 用这种方式组装的json数组是错误的，接收侧只能接收到整个的这个字符串            
          var employees='[';
          for ( var j = 0; j < 5; j++) {                          
            employees+= '{';                             
            employees+="name:";                            
            employees+="zhang";
            employees+=",";
            employees+="old:";                            
            employees+=30 + j;
            employees +='}';
            if(j!=4){                             
                employees+=','
            };                         
          } 
          employees+=']';
          alert("employees=" + employees);
          
           $.ajax({
                type:"POST", //请求方式  
                url:"./testJson", //请求路径  
                cache: false,     
                data:{//传参  
                    "name":"zhang3",
                    "testArray":testArray,    
                    "students": //用这种方式传递多维数组也是正确的
                        [
                            {"name":"jackson","age":100},
                            {"name":"michael","age":51}
                        ],
                    "employees":employees,
                    "jsonArr":jsonArr    
                },
                dataType: 'json',   //返回值类型  
                success:function(json){        
                    alert(json[0].username+" " + json[0].password);    //弹出返回过来的List对象  
                    alert(json[1].username+" " + json[1].password);    //弹出返回过来的List对象
                }  
            });  
      }  
    </script>  
  </head>  
    
  <body>  
    <input type="button" name="b" value="TestJson" onclick="test2()"/>
  </body>  

</html>

TestJson.java

package com.zm.servlet;  
  
import java.io.BufferedReader;
import java.io.IOException;  
import java.io.PrintWriter;  
import java.util.ArrayList;  
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;  
import java.util.Map;
  
import javax.servlet.ServletException;  
import javax.servlet.http.HttpServlet;  
import javax.servlet.http.HttpServletRequest;  
import javax.servlet.http.HttpServletResponse;  
import javax.servlet.http.HttpSession;
  
import net.sf.json.JSONArray;  
import net.sf.json.JSONObject;
  
public class TestJson extends HttpServlet {  
  
    public void doGet(HttpServletRequest request, HttpServletResponse response)  
            throws ServletException, IOException {  
           doPost(request,response);  
    }  
    public void doPost(HttpServletRequest request, HttpServletResponse response)  
            throws ServletException, IOException {  
        response.setContentType("text/html");
        System.out.println("into doPost");
        
        //用map来接收request发送过来的多维数组
        Map map = request.getParameterMap();
        Iterator<String> iter = map.keySet().iterator();
        while (iter.hasNext()) {
            String key = iter.next();
            System.out.println("key=" + key );
            String[] value =  (String[]) map.get(key);
            System.out.print("value=");
            for(String v:value){                
                System.out.print(v + "  ");
            }            
            System.out.println();
        }        
        
        String sName= request.getParameter("name");//得到ajax传递过来的paramater  
        System.out.println(sName);

        PrintWriter printWriter = response.getWriter();  
        List list = new ArrayList();//传递List  
        
        Map m=new HashMap();//传递Map      
        User u1=new User();  
        u1.setUsername("zah");  
        u1.setPassword("123");  
        User u2=new User();  
        u2.setUsername("ztf");  
        u2.setPassword("456");    
        list.add(u1); //添加User对象        
        list.add(u2);     //添加User对象    
        
        m.put("u1", u1);  
        m.put("u2", u2);     
          
        JSONArray jsonArray2 = JSONArray.fromObject( list );  
        //把java数组转化成转化成json对象   
        //JSONObject jsonObject =JSONObject.fromObject(m);//转化Map对象  
        printWriter.print(jsonArray2);//返给ajax请求  
        //printWriter.print(jsonObject);//返给ajax请求  
        printWriter.flush();
        printWriter.close();
        System.out.println("finish");
    }  
}

web.xml:

    <!-- 测试jquery json-->
    <servlet>  
    <servlet-name>testJson</servlet-name>  
    <servlet-class>com.zm.servlet.TestJson</servlet-class>  
  </servlet>  
   <servlet-mapping>  
    <servlet-name>testJson</servlet-name>  
    <url-pattern>/testJson</url-pattern>  
  </servlet-mapping>