android使用JSON进行网络数据交换(服务端、客户端)的实现

服务端需要加上json.jar包，下载地址：https://github.com/upictec/org.json.me

服务端：

JSONDemoServlet.java

package com.test.Demo;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.me.JSONArray;
import org.json.me.JSONObject;

publicclass JSONDemoServlet extends HttpServlet {
 privatestaticfinallong serialVersionUID =-7368225680407826408L; 
 private List<User> list;
 
 /**
 * 处理post方式提交的数据
 */
 @Override
 protectedvoid doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
 // TODO Auto-generated method stub
 doGet(request, response);
 }
 
 /**
 * 处理get方式提交的数据
 */
 @Override
 protectedvoid doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
 // TODO Auto-generated method stub
 response.setContentType("text/plain");
 response.setCharacterEncoding("UTF-8");
 PrintWriter out = response.getWriter();
 
 //准备用户数据 
 prepareData();
 
 //JSON数组 
 JSONArray array =new JSONArray();
 
 for(User bean:list){
 //单个用户JSON对象 
 JSONObject obj =new JSONObject(); 
 try{
 
 obj.put("id", bean.getId());
 obj.put("name", bean.getName());
 obj.put("email", bean.getEmail());
 obj.put("gender", bean.getGender()); 
 }catch (Exception e) {
 // TODO: handle exception
 }
 array.put(obj); 
 } 
 //输出 
 out.write(array.toString()); 
 out.flush(); 
 out.close(); 
 } 
 
 
 privatevoid prepareData()
 {
 list =new ArrayList<User>();
 User bean1 =new User();
 bean1.setId(1001); 
 bean1.setName("Tony"); 
 bean1.setEmail("tony@toeach.net"); 
 bean1.setGender("male"); 
 list.add(bean1); 
 
 User bean2 =new User();
 bean2.setId(1002);
 bean2.setName("Jack"); 
 bean2.setEmail("jack@hotmail.com");
 bean2.setGender("male"); 
 list.add(bean2); 
 
 User bean3 =new User();
 bean3.setId(1003); 
 bean3.setName("Marry");
 bean3.setEmail("marry@163.com");
 bean3.setGender("female");
 list.add(bean3);
 
 User bean4 =new User();
 bean4.setId(1004); 
 bean4.setName("Linda");
 bean4.setEmail("linda@21cn.com"); 
 bean4.setGender("female"); 
 list.add(bean4); 
 }
 
}

User.java

package com.test.Demo;

publicclass User {
 privateint id;

 private String name;

 private String email;

 private String gender;

 public String getEmail() {
 return email;
 }

 publicvoid setEmail(String email) {
 this.email = email;
 }

 public String getGender() {
 return gender;
 }

 publicvoid setGender(String gender) {
 this.gender = gender;
 }

 publicint getId() {
 return id;
 }

 publicvoid setId(int id) {
 this.id = id;
 }

 public String getName() {
 return name;
 }

 publicvoid setName(String name) {
 this.name = name;
 }

}

web.xml中配置映射路径：

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
 xmlns="http://java.sun.com/xml/ns/javaee" 
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

 <servlet>
 <servlet-name>JSONDemoServlet</servlet-name>
 <servlet-class>com.test.Demo.JSONDemoServlet</servlet-class>
 </servlet>
 
 <servlet-mapping>
 <servlet-name>JSONDemoServlet</servlet-name>
 <url-pattern>/JSONDemoServlet</url-pattern>
 </servlet-mapping>
 
 
 <welcome-file-list>
 <welcome-file>index.jsp</welcome-file>
 </welcome-file-list>
 
</web-app>

客户端：

package com.test;

import java.io.BufferedReader;
import java.io.InputStreamReader;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.json.JSONArray;
import org.json.JSONObject;

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

publicclass MainActivity extends Activity {
 /** Called when the activity is first created. */
 @Override
 publicvoid onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);

 try {
 StringBuffer sb =new StringBuffer();
 // 在测试过程中，经常是用本机做测试服务器，访问本机的IP地址要设置为10.0.2.2
 String url ="http://10.0.2.2:8080/article/JSONDemoServlet";
 String body = getContent(url);
 JSONArray array =new JSONArray(body);
 for (int i =0; i < array.length(); i++) {
 JSONObject obj = array.getJSONObject(i);
 sb.append("id:").append(obj.getInt("id")).append("\t");
 sb.append("name:").append(obj.getString("name")).append("\r\n");
 sb.append("gender:").append(obj.getString("gender")).append(
 "\t");
 sb.append("email:").append(obj.getString("email")).append(
 "\r\n");
 sb.append("----------------------\r\n");
 }
 TextView textView = (TextView) findViewById(R.id.textView);
 textView.setText(sb.toString());
 } catch (Exception e) {
 // TODO: handle exception
 }

 }

 private String getContent(String url) throws Exception {
 StringBuilder sb =new StringBuilder();
 HttpClient client =new DefaultHttpClient();
 HttpParams httpParams = client.getParams();

 // 设置网络超时参数
 HttpConnectionParams.setConnectionTimeout(httpParams, 3000);
 HttpConnectionParams.setSoTimeout(httpParams, 5000);
 HttpResponse response = client.execute(new HttpGet(url));
 HttpEntity entity = response.getEntity();
 if (entity !=null) {
 BufferedReader reader =new BufferedReader(new InputStreamReader(
 entity.getContent(), "UTF-8"), 8192);
 String line =null;
 while ((line = reader.readLine()) !=null) {
 sb.append(line +"\n");
 }
 reader.close();
 }

 return sb.toString();
 }

}

服务端截图：

客户端截图：