在网络上传输数据时最常用的格式有两种:XML和JSON,今天学习如何解析JSON格式的数据。

接着上一章XML解析。在Apache的htdocs目录下,新建一个get_data.json文件,内容如下:

[{"id":"5","version":"5.5","name":"Clash of Clans"},
{"id":"6","version":"7.0","name":"Boom Beach"},
{"id":"7","version":"3.5","name":"Clash Royale"}]

在浏览器中验证 http://10.39.131.104/get_data.json 可以访问 (IP依据实际情况而定)

1、使用JSONObject

布局文件activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     tools:context=".MainActivity">    <Button
         android:id="@+id/send_request"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="Send Request"/>    <ScrollView
         android:layout_width="match_parent"
         android:layout_height="match_parent">        <TextView
             android:id="@+id/response_text"
             android:layout_width="match_parent"
             android:layout_height="wrap_content" />
     </ScrollView></LinearLayout>


 

主MainActivity

package com.example.networktest;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import org.json.JSONArray;
import org.json.JSONObject;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.URL;

import javax.net.ssl.HttpsURLConnection;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParserFactory;

import okhttp3.FormBody;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

public class MainActivity extends AppCompatActivity {

    TextView responseText;
    Response response;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final Button sendRequest = (Button) findViewById(R.id.send_request);
        responseText = (TextView) findViewById(R.id.response_text);
        sendRequest.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                sendRequestWithOkHttp();
            }
        });
    }

    private void sendRequestWithOkHttp(){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    OkHttpClient client = new OkHttpClient();
                    Request request = new Request.Builder()
                            .url("http://10.39.131.104/get_data.json")
                            .build();
                    response = client.newCall(request).execute();
                    String responseData = response.body().string();
                    Log.d("MainActivity", "--responseData--"+responseData);
//                    parseXMLWithPull(responseData);
//                    parseXMLWithSAX(responseData);
                    parseJSONWithJSONObject(responseData);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }

    private void parseJSONWithJSONObject(String jsonData){
        try {
            JSONArray jsonArray = new JSONArray(jsonData);
            for (int i = 0 ; i < jsonArray.length(); i++){
                JSONObject jsonObject = jsonArray.getJSONObject(i);
                String id = jsonObject.getString("id");
                String version = jsonObject.getString("version");
                String name = jsonObject.getString("name");
                Log.d("MainActivity", "id is :"+id);
                Log.d("MainActivity", "version is :"+version);
                Log.d("MainActivity", "name is :"+name);
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }

}

运行效果(点击button)

android发送json数据到服务器 安卓json格式怎么打开_json

2、使用GSON

在build.gradle中添加包依赖

dependencies {
    ......
    compile 'com.google.code.gson:gson:2.7'
}

GSON库主要是可以将一段JSON格式字符串自动映射成一个对象,从而不需要我们手动去编写代码去解析。

新建解析类App

package com.example.networktest;

public class App {

    private String id;

    private String name;

    private String version;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getVersion() {
        return version;
    }

    public void setVersion(String version) {
        this.version = version;
    }
}

在MainActiity中修改

public class MainActivity extends AppCompatActivity {

    ......

    private void sendRequestWithOkHttp(){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    OkHttpClient client = new OkHttpClient();
                    Request request = new Request.Builder()
                            .url("http://192.168.31.108/get_data.json")
                            .build();
                    response = client.newCall(request).execute();
                    String responseData = response.body().string();
                    Log.d("MainActivity", "--responseData--"+responseData);
//                    parseXMLWithPull(responseData);
//                    parseXMLWithSAX(responseData);
//                    parseJSONWithJSONObject(responseData);
                    parseJSONWithGSON(responseData);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }

    private void  parseJSONWithGSON(String jsonData){
        Gson gson = new Gson();
        List<App> appList = gson.fromJson(jsonData, new TypeToken<List<App>>()
                            {}.getType());
        for (App app: appList){
            Log.d("MainActivity", "id is :"+app.getId());
            Log.d("MainActivity", "name is :"+app.getName());
            Log.d("MainActivity", "version is :"+app.getVersion());
        }
    }

}

运行效果

android发送json数据到服务器 安卓json格式怎么打开_Android JSONObject_02