最近在给公司做一个直播APK的项目,主要就是通过解析网络服务器上的json数据,然后将频道地址下载下来再调用Android的播放器进行播放,原先本来打算使用普通的json解析方法即JsonObject和JsonArray的配合使用,这对于解析小数据的json数据还是比较实用,但是当解析json数据比较复杂的时候这种方法就显得比较吃力也比较麻烦了,如果大家感兴趣的话网上有大量的实例可以到网上去看看。

          在这里我将介绍解析json数据的另外一种方法就是通过Gson解析,对于解析比较简单的json数据我就不介绍了来一个比较复杂一点的json数据,如下面我们要解析的一个json数据:



1 String json = {"a":"100","b":[{"b1":"b_value1","b2":"b_value2"}, {"b1":"b_value1","b2":"b_value2"}],"c": {"c1":"c_value1","c2":"c_value2"}}


如果使用JsonObject和JsonArray的配合起来使用也是可以解析的但是解析起来就比较麻烦了,如果使用Gson解析就比较简单了,首先我们需要定义一个序列化的Bean,这里采用内部类的形式,这样比较容易看得清晰些



首先我们需要定义一个序列化的Bean,这里采用内部类的形式,看起来会比较清晰一些:



1 public class JsonBean {
2 public String a;
3 public List<B> b;
4 public C c;
5
6 public static class B {
7
8 public String b1;
9
10 public String b2;
11 }
12
13 public static class C {
14 public String c1;
15 public String c2;
16 }
17 }


很多时候大家都是不知道这个Bean是该怎么定义,这里面需要注意几点:

             1、内部嵌套的类必须是static的,要不然解析会出错;

             2、类里面的属性名必须跟Json字段里面的Key是一模一样的;

             3、内部嵌套的用[]括起来的部分是一个List,所以定义为 public List<B> b,而只用{}嵌套的就定义为 public C c,

                  具体的大家对照Json字符串看看就明白了,不明白的我们可以互相交流,本人也是开发新手!



1              Gson gson = new Gson();
2 java.lang.reflect.Type type = new TypeToken<JsonBean>() {}.getType();
3 JsonBean jsonBean = gson.fromJson(json, type);</span>


然后想拿数据就很简单啦,直接在jsonBean里面取就可以了!

       如果需要解析的Json嵌套了很多层,同样可以可以定义一个嵌套很多层内部类的Bean,需要细心的对照Json字段来定义哦。


       下面我将以一个具体的列子来说明通过Gson方式解析复杂的json数据

1.将要解析的数据如下面的格式


{

    "error": 0,

    "status": "success",

    "date": "2014-05-10",

    "results": [

        {

            "currentCity": "南京",

            "weather_data": [

                {

                    "date": "周六(今天, 实时:19℃)",

                    "dayPictureUrl": "http://api.map.baidu.com/images/weather/day/dayu.png",

                    "nightPictureUrl": "http://api.map.baidu.com/images/weather/night/dayu.png",

                    "weather": "大雨",

                    "wind": "东南风5-6级",

                    "temperature": "18℃"

                },

                {

                    "date": "周日",

                    "dayPictureUrl": "http://api.map.baidu.com/images/weather/day/zhenyu.png",

                    "nightPictureUrl": "http://api.map.baidu.com/images/weather/night/duoyun.png",

                    "weather": "阵雨转多云",

                    "wind": "西北风4-5级",

                    "temperature": "21 ~ 14℃"

                }

            ]

        }

    ]

}

2.必须定义如下一些的javaBean数据

Status.java



1 public class Status 
2 {
3 private String error;
4 private String status;
5 private String date;
6 private List<Results> results;
7 public String getError()
8 {
9 return error;
10 }
11 public void setError(String error)
12 {
13 this.error = error;
14 }
15
16 public String getStatus()
17 {
18 return status;
19 }
20 public void setStatus(String status)
21 {
22 this.status = status;
23 }
24 public String getDate()
25 {
26 return date;
27 }
28 public void setDate(String date)
29 {
30 this.date = date;
31 }
32 public List<Results> getResults()
33 {
34 return results;
35 }
36 public void setResults(List<Results> results)
37 {
38 this.results = results;
39 }
40 @Override
41 public String toString()
42 {
43 return "Status [error=" + error + ", status=" + status
44 + ", date=" + date + ", results=" + results + "]";
45 }
46 </span>


Results.java



1 public class Results 
2 {
3 private String currentCity;
4 private List<Weather> weather_data;
5 public String getCurrentCity()
6 {
7 return currentCity;
8 }
9 public void setCurrentCity(String currentCity)
10 {
11 this.currentCity = currentCity;
12 }
13 public List<Weather> getWeather_data()
14 {
15 return weather_data;
16 }
17 public void setWeather_data(List<Weather> weather_data)
18 {
19 this.weather_data = weather_data;
20 }
21 @Override
22 public String toString()
23 {
24 return "Results [currentCity=" + currentCity + ", weather_data="
25 + weather_data + "]";
26 }


Weather.java



1 public class Weather {
2 private String date;
3 private String dayPictureUrl;
4 private String nightPictureUrl;
5 private String weather;
6 private String wind;
7 private String temperature;
8 public String getDate() {
9 return date;
10 }
11 public void setDate(String date) {
12 this.date = date;
13 }
14 public String getDayPictureUrl() {
15 return dayPictureUrl;
16 }
17 public void setDayPictureUrl(String dayPictureUrl) {
18 this.dayPictureUrl = dayPictureUrl;
19 }
20 public String getNightPictureUrl() {
21 return nightPictureUrl;
22 }
23 public void setNightPictureUrl(String nightPictureUrl) {
24 this.nightPictureUrl = nightPictureUrl;
25 }
26 public String getWeather() {
27 return weather;
28 }
29 public void setWeather(String weather) {
30 this.weather = weather;
31 }
32 public String getWind() {
33 return wind;
34 }
35 public void setWind(String wind) {
36 this.wind = wind;
37 }
38 public String getTemperature() {
39 return temperature;
40 }
41 public void setTemperature(String temperature) {
42 this.temperature = temperature;
43 }
44 @Override
45 public String toString() {
46 return "Weather [date=" + date + ", dayPictureUrl="
47 + dayPictureUrl + ", nightPictureUrl="
48 + nightPictureUrl + ", weather=" + weather
49 + ", wind=" + wind + ", temperature=" + temperature
50 + "]";
51 }
52


然后具体的javabean定义好了就将解析数据了,下面就是我的解析数据类



1 public class MainActivity extends Activity 
2 {
3 private Button tojson;
4 RequestQueue mQueue;
5 StringRequest stringRequest;
6 Gson gson;
7 String str;
8
9 &nbsp; @Override
10 protected void onCreate(Bundle savedInstanceState)
11 {
12 super.onCreate(savedInstanceState);
13 setContentView(R.layout.activity_main);
14
15 tojson = (Button)findViewById(R.id.tojson);
16 gson = new Gson();
17
18 mQueue = Volley.newRequestQueue(MainActivity.this);
19 //http://10.19.20.12/upgrade/test.txt是测试使用的json数据
20 stringRequest = new StringRequest("http://10.19.20.12/upgrade/test.txt",
21 new Response.Listener<String>()
22 {
23 @Override
24 public void onResponse(String response)
25 {
26 Log.d("TAG", response);
27 System.out.println("response="+response);
28 Status status = gson.fromJson(response, Status.class);
29 System.out.println("status="+status);
30 System.out.println("-------------------------------------");
31 List<Results> result = status.getResults();
32 System.out.println("result="+result);
33
34 }
35 },
36 new Response.ErrorListener()
37 {
38 @Override
39 public void onErrorResponse(VolleyError error)
40 {
41 Log.e("TAG", error.getMessage(), error);
42 }
43
44 });
45
46 tojson.setOnClickListener(new OnClickListener()
47 {
48 @Override
49 public void onClick(View v)
50 {
51 mQueue.add(stringRequest);
52 }
53 });
54 }
55
56
57
58 }


其中上面的RequestQueue是开源网络库Volley的使用,如果你对该库的使用还不熟悉的话可以参考前面的文章,其中对Volley的讲解也很详细了,相信各位朋友很快便能领悟出来。