ApplicationModule.java

@Module
public class ApplicationModule {

    private Application mApplication;

    public ApplicationModule(Application application) {
        mApplication = application;
    }

    @Provides
    Application provideApplication() {
        return mApplication;
    }

    @Provides
    @ApplicationContext
    Context provideContext() {
        return mApplication;
    }

    @Provides
    @Singleton
    public Retrofit getRetrofit(OkHttpClient client) {

        return new Retrofit.Builder()
                .addConverterFactory(GsonConverterFactory.create())
                .client(client)
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .baseUrl(BuildConfig.BASE_URL)
                .build();
    }

    @Provides
    @Singleton
    OkHttpClient getOkHttpClient() {
        return new WeatherOkhttp().getWeatherOkhttpClient();
    }

}