使用Gson解析Json数据案例

来源：互联网发布：alfred mac app store 编辑：程序博客网时间：2024/05/30 19:33

代码托管地址：https://github.com/SleepyzzZ/HttpGsonDemo

最近在做Android远程控制sony相机的项目，主要通过http实现手机端与相机端的通信，其中通信协议用的是json数据格式。原本使用自带的API即JsonObject和JsonArray的配合使用来实现数据传输，之后改用goole的Gson来生成和解析Json数据。

话不多说，为了学会使用Gson，我们直接以案例的形式快速入门。

首先给出手机端和sony相机端的通信协议(此文档来自sony android api)

案例1：

案例2：

针对案例1所示的JsonExample创建序列化的Bean:

package com.sleepyzzz.httpjsontest.bean;import java.util.Collection;import java.util.List;/** * User: datou_SleepyzzZ(SleepyzzZ19911002@126.com) * Date: 2016-05-30 * Time: 13:32 * FIXME */public class WhiteBalance {    public WhiteBalance(String method, List params, int id, String version) {        this.method = method;        this.params = params;        this.id = id;        this.version = version;    }    private String method;    private List params;    private int id;    private String version;    public String getMethod() {        return method;    }    public void setMethod(String method) {        this.method = method;    }    public Collection getParams() {        return params;    }    public void setParams(List params) {        this.params = params;    }    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getVersion() {        return version;    }    public void setVersion(String version) {        this.version = version;    }    @Override    public String toString() {        // TODO Auto-generated method stub        return "method: "+method+"\n"                +"params: "+params.get(0)+","+params.get(1)+","+params.get(2)+"\n"                +"id: "+id+"\n"                +"version: "+version+"\n";    }}

针对案例2所示的JsonExample创建序列化的Bean:

package com.sleepyzzz.httpjsontest.bean;import java.util.List;/** * User: datou_SleepyzzZ(SleepyzzZ19911002@126.com) * Date: 2016-05-30 * Time: 14:50 * FIXME */public class TrackFocus {    private int id;    private String method;    private List<FocusPoint> params;    private String version;    public TrackFocus(int id, String method, List<FocusPoint> params, String version) {        this.id = id;        this.method = method;        this.params = params;        this.version = version;    }    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getMethod() {        return method;    }    public void setMethod(String method) {        this.method = method;    }    public List<FocusPoint> getParams() {        return params;    }    public void setParams(List<FocusPoint> params) {        this.params = params;    }    public String getVersion() {        return version;    }    public void setVersion(String version) {        this.version = version;    }    @Override    public String toString() {        return "id: "+id+"\n"                +"method: "+method+"\n"                +"params: "+params.get(0).getxPosition()+","+params.get(0).getyPosition()+"\n"                +"version: "+version+"\n";    }}

package com.sleepyzzz.httpjsontest.bean;/** * User: datou_SleepyzzZ(SleepyzzZ19911002@126.com) * Date: 2016-05-30 * Time: 14:51 * FIXME */public class FocusPoint {    private double xPosition;    private double yPosition;    public FocusPoint(double xPosition, double yPosition) {        this.xPosition = xPosition;        this.yPosition = yPosition;    }    public double getxPosition() {        return xPosition;    }    public void setxPosition(double xPosition) {        this.xPosition = xPosition;    }    public double getyPosition() {        return yPosition;    }    public void setyPosition(double yPosition) {        this.yPosition = yPosition;    }}

这里为了测试方便直接写一个servlet服务端demo用于与手机端通信：

package com.sleepyzzz.servlet;import java.io.IOException;import java.io.PrintWriter;import java.util.ArrayList;import java.util.List;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.google.gson.Gson;/** * Servlet implementation class gsonserver */@WebServlet("/gsonserver")public class gsonserver extends HttpServlet {private static final long serialVersionUID = 1L;    /**     * @see HttpServlet#HttpServlet()     */    public gsonserver() {        super();        // TODO Auto-generated constructor stub    }/** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubdoPost(request, response);}/** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubresponse.setContentType("text/html;charset=utf-8");PrintWriter writer = response.getWriter();Gson gson = new Gson();/*String WTstr = request.getParameter("jsonWT");WhiteBalance WTbean = gson.fromJson(WTstr, WhiteBalance.class);System.out.println(WTbean.toString());*///解析来自客户端的Json数据String TFstr = request.getParameter("jsonTF");TrackFocus TFbean = gson.fromJson(TFstr, TrackFocus.class);System.out.println(TFbean.toString());List<Integer> result = new ArrayList<Integer>();result.add(0);Result responseBean = new Result(result, 1);String resJsonString = gson.toJson(responseBean, Result.class);writer.println(resJsonString);}}

这里只给出案例2的测试结果，其他不在赘述

大致流程：Android端生成Json发给服务端，服务端解析数据后返回Json格式，最后Android端解析服务器端返回的数据。

Android端代码片段：

package com.sleepyzzz.httpjsontest;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.Button;import android.widget.TextView;import com.google.gson.Gson;import com.sleepyzzz.httpjsontest.bean.FocusPoint;import com.sleepyzzz.httpjsontest.bean.Result;import com.sleepyzzz.httpjsontest.bean.TrackFocus;import com.sleepyzzz.httpjsontest.bean.WhiteBalance;import com.sleepyzzz.httpjsontest.okhttp.OkHttpUtils;import com.sleepyzzz.httpjsontest.okhttp.callback.StringCallback;import java.util.ArrayList;import java.util.List;import butterknife.Bind;import butterknife.ButterKnife;import butterknife.OnClick;import okhttp3.Call;public class MainActivity extends AppCompatActivity {    private static final String URL = "http://10.10.77.129:8080/HttpGsonServer/gsonserver";    @Bind(R.id.btn_whitebalance)    Button mBtnWhitebalance;    @Bind(R.id.tv_whitebalance)    TextView mTvWhitebalance;    @Bind(R.id.tv_response1)    TextView mTvResponse1;    @Bind(R.id.btn_trackfocus)    Button mBtnTrackfocus;    @Bind(R.id.tv_trackfocus)    TextView mTvTrackfocus;    @Bind(R.id.tv_response2)    TextView mTvResponse2;    private String jsonStr;    private Gson mGson;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ButterKnife.bind(this);        mGson = new Gson();    }    //生成Json格式数据-案例1    private void generateWTJson() {        List params = new ArrayList();        params.add("Color Temperature");        params.add(true);        params.add(2500);        WhiteBalance bean = new WhiteBalance("setWhiteBalance",                params, 1, "1.0");        jsonStr = mGson.toJson(bean);        mTvWhitebalance.setText("request: "+jsonStr);    }    //生成Json格式数据-案例2    private void generateTFJson() {        List<FocusPoint> points = new ArrayList<FocusPoint>();        points.add(new FocusPoint(23.4,45.6));        TrackFocus trackFocus = new TrackFocus(1, "actTrackingFocus",                points, "1.0");        jsonStr = mGson.toJson(trackFocus);        mTvTrackfocus.setText("request: "+jsonStr);    }    @OnClick({R.id.btn_whitebalance, R.id.btn_trackfocus})    public void onClick(View view) {        switch (view.getId()) {            case R.id.btn_whitebalance:                generateWTJson();                OkHttpUtils.post()                        .url(URL)                        .addParams("jsonWT", jsonStr)                        .build()                        .execute(new StringCallback() {                            @Override                            public void onError(Call call, Exception e) {                            }                            //解析Json格式数据-案例1                            @Override                            public void onResponse(String response) {                                Result result = mGson.fromJson(response, Result.class);                                mTvResponse1.setText("response: "+result.toString());                            }                        });                break;            case R.id.btn_trackfocus:                generateTFJson();                OkHttpUtils.post()                        .url(URL)                        .addParams("jsonTF", jsonStr)                        .build()                        .execute(new StringCallback() {                            @Override                            public void onError(Call call, Exception e) {                            }                            //解析Json格式数据-案例2                            @Override                            public void onResponse(String response) {                                Result result = mGson.fromJson(response, Result.class);                                mTvResponse2.setText("response: "+result.toString());                            }                        });                break;        }    }}

测试结果：

Android端

服务器端：

0 0