保定阿里云代理商：android获取服务器json数据类型

Android获取服务器返回的JSON数据类型有以下几种方式：

方式一：使用Android自带的JSONObject和JSONArray解析JSON数据，代码如下：

String jsonString = "{'name':'Tom','age':18,'address':{'city':'Beijing','road':'No.11'}}";
try {
    JSONObject jsonObject = new JSONObject(jsonString);
    String name = jsonObject.getString("name");
    int age = jsonObject.getInt("age");
    JSONObject addressObject = jsonObject.getJSONObject("address");
    String city = addressObject.getString("city");
    String road = addressObject.getString("road");
    Log.d("JSON", "name:" + name + ",age:" + age + ",city:" + city + ",road:" + road);
} catch (JSONException e) {
    e.printStackTrace();
}

方式二：使用第三方库Gson解析JSON数据，代码如下：

String jsonString = "{'name':'Tom','age':18,'address':{'city':'Beijing','road':'No.11'}}";
Gson gson = new Gson();
Person person = gson.fromJson(jsonString, Person.class);
Log.d("Gson", person.toString());

其中Person类的定义如下：

public class Person {
    private String name;
    private int age;
    private Address address;

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public Address getAddress() {
        return address;
    }

    public void setAddress(Address address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "name:" + name + ",age:" + age + ",address:" + address.toString();
    }
}

public class Address {
    private String city;
    private String road;

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getRoad() {
        return road;
    }

    public void setRoad(String road) {
        this.road = road;
    }

    @Override
    public String toString() {
        return "city:" + city + ",road:" + road;
    }
}

方式三：使用RxJava和Retrofit结合解析JSON数据，代码如下：

public interface ApiService {
    @GET("api")
    Observable<Person> getPerson();
}

public class RetrofitManager {
    private static final String HOST = "http://xxx.xxx.xxx.xxx/";
    private ApiService apiService;

    private RetrofitManager() {
        OkHttpClient httpClient = new OkHttpClient.Builder().build();
        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(HOST)
                .addConverterFactory(GsonConverterFactory.create())
                .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
                .client(httpClient)
                .build();
        apiService = retrofit.create(ApiService.class);
    }

    public static RetrofitManager getInstance() {
        return SingletonHolder.INSTANCE;
    }

    private static class SingletonHolder {
        private static final RetrofitManager INSTANCE = new RetrofitManager();
    }

    public Observable<Person> getPerson() {
        return apiService.getPerson();
    }
}

RetrofitManager.getInstance().getPerson()
        .subscribeOn(Schedulers.io())
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe(new Subscriber<Person>() {
            @Override
            public void onCompleted() {

            }

            @Override
            public void onError(Throwable e) {
                e.printStackTrace();
            }

            @Override
            public void onNext(Person person) {
                Log.d("Retrofit", person.toString());
            }
        });

需要注意的是：第三种方式需要引入RxJava和Retrofit的依赖库。

Android获取服务器json数据类型可以使用HttpURLConnection或者OkHttp，再利用JSON.parseObject()方法将JSON字符串转化为Java对象。

使用HttpURLConnection获取JSON数据：

public String httpURLConnectionMethod(String urlString) throws IOException {
   URL url = new URL(urlString);
   HttpURLConnection conn = (HttpURLConnection) url.openConnection();
   conn.setRequestMethod("GET");
   conn.connect();
   String result = convertStreamToString(conn.getInputStream()); //转换输入流为 String
   return result;
}

private String convertStreamToString(InputStream is) throws IOException {
   BufferedReader reader = new BufferedReader(new InputStreamReader(is));
   StringBuilder sb = new StringBuilder();
   String line = null;
   while ((line = reader.readLine()) != null) {
       sb.append(line + "n");
   }
   is.close();
   return sb.toString();
}

使用OkHttp获取JSON数据：

public String okHttpMethod(String url) throws IOException {
   OkHttpClient client = new OkHttpClient();
   Request request = new Request.Builder()
           .url(url)
           .build();
   Response response = client.newCall(request).execute();
   String result = response.body().string();
   return result;
}

将获取到的JSON数据转换为Java对象：

String jsonStr = httpURLConnectionMethod(urlString);
User user = JSON.parseObject(jsonStr, User.class);

以上代码中的 User 类是你定义的 Java 对象类，可以根据 JSON 数据的结构来定义。例如，如果 JSON 数据的结构如下：

{
   "name": "Mike",
   "age": 22,
   "gender": "male"
}

则可以定义如下的 User 类：

public class User {
   private String name;
   private int age;
   private String gender;

   // getter and setter methods here

}