Retrofit

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What about Retrofit?

Setting up Retrofit

 compile 'com.squareup.retrofit:retrofit:1.9.0'

 compile 'com.squareup.okhttp:okhttp-urlconnection:2.0.0' 
 compile 'com.squareup.okhttp:okhttp:2.0.0'

Requesting | GET Query

HttpUrlConnection-way

HttpURLConnection getTodoConnection = null;
try {
    getTodoConnection = (HttpURLConnection) mGetQueryUrl.openConnection();
} catch (IOException e) {
    Log.e(TAG, "Error: " + e.getMessage());
}

try {
    String response = parseResponse(getTodoConnection.getInputStream());
} catch (IOException e) {
    Log.e(TAG, "Error: " + e.getMessage());
} finally {
    getTodoConnection.disconnect();
}

// Send response somewhere (eg. Event bus or LocalBroadcastReceiver)

Requesting | GET Query

Retrofit-way

public interface TodoApi {

    @GET("/todos")
    void getTodosByUserId(@Query("userId") Long userId, Callback<Todo[]> todos);

}

... then create a RestAdapter once and create,

RestAdapter restAdapter = new RestAdapter.Builder().setEndpoint(Api.BASE_URL).build();
mTodoApi = restAdapter.create(TodoApi.class);

mTodoApi.getTodosByUserId(1L, new Callback<Todo[]>() {
    @Override
    public void success(Todo[] todos, Response response) {
        // Do something on success
    }

    @Override
    public void failure(RetrofitError error) {
        // Do something on failure
    }
});

Requesting | POST

public interface TodoApi {
    @FormUrlEncoded
    @POST("/todos")
    void addTodo(@Field("userId") Long userId, @Field("id") Long id, 
                 @Field("title") String title, @Field("completed") boolean completed, 
                 Callback<Todo> todo);

    @POST("/todos")
    void addTodo(@Body Todo newTodo, Callback<Todo> todo);
}

mTodoApi.addTodo(newTodo, new Callback<Todo>() {
    @Override
    public void success(Todo todo, Response response) {
        // Do something on success
    }

    @Override
    public void failure(RetrofitError error) {
        // Do something on failure
    }
});

Requesting

Requesting | Request Interceptors

public class ThrottlingInterceptor implements RequestInterceptor {
   private static final String TAG = ThrottlingInterceptor.class.getSimpleName();

   private long lastRequest = 0L;
   private final long maxRequestSpeed;
   private final Lock requestLock = new ReentrantLock();
   
   public ThrottlingInterceptor(long maxRequestSpeed) {
      this.maxRequestSpeed = maxRequestSpeed;
   }

   @Override
   public void intercept(RequestFacade request) {
      requestLock.lock();
      
      try {
         long curTime = System.currentTimeMillis();
         long diff = curTime - lastRequest;

         if (diff < maxRequestSpeed)
            try {
               Thread.sleep(maxRequestSpeed - diff);
            } catch (InterruptedException e) {
               Log.e(TAG, "Error: " + e.getMessage());
            }

         lastRequest = System.currentTimeMillis();
      } finally { requestLock.unlock(); }
   }
}

Requesting | Request Interceptors

RestAdapter restAdapter = new RestAdapter.Builder()
        // Throttle every 1s
        .setRequestInterceptor(new ThrottlingInterceptor(1000)) 
        .setEndpoint(Api.BASE_URL).build();
mTodoApi = restAdapter.create(TodoApi.class);

Requesting | Error Handler

public class TodoErrorHandler implements ErrorHandler {
    // Variable declarations and constructor...
    
    @Override
    public Throwable handleError(RetrofitError cause) {
        if (cause.getKind() == RetrofitError.Kind.NETWORK) {
            mToastHandler.post(new Runnable() {
                @Override
                public void run() {
                    Toast.makeText(mContext, R.string.error_network, Toast.LENGTH_SHORT).show();
                }
            });
        } else if (cause.getKind() == RetrofitError.Kind.HTTP) {
            mToastHandler.post(new Runnable() {
                @Override
                public void run() {
                    Toast.makeText(mContext, R.string.error_http, Toast.LENGTH_SHORT).show();
                }
            });
        }        
        return cause.getCause();
    }
}

Benchmark

Retrofit 2.0

END