DataManager.java

public class DataManager {

  public void getArticles(final DataManagerCallBacks dataManagerCallBacks){

        Call<UserResponse> call = this.apiService.getArticlesList();
        call.enqueue(new Callback<UserResponse>() {
            @Override
            public void onResponse(Call<UserResponse> call, Response<UserResponse> response) {

                if(response.isSuccessful()){
                    UserResponse userResponse = response.body();
                    dataManagerCallBacks.onSuccess(userResponse);
                }else{

                }
            }
            
            @Override
            public void onFailure(Call<UserResponse> call, Throwable t) {
                dataManagerCallBacks.onError(t);
            }
        });

    }




    public interface DataManagerCallBacks<T>{
        void onSuccess( T onSucces);
        void onError(Throwable onError);
    }
  
}