MediatorLiveData for retrofit response

CustomApiCallback.java

import android.arch.lifecycle.MediatorLiveData;
import android.arch.lifecycle.MutableLiveData;
import android.arch.lifecycle.Observer;

import com.abhinav.basemvvmsample.data.model.FailureResponse;

import java.net.SocketTimeoutException;
import java.net.UnknownHostException;

import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;

public abstract class CustomApiCallback<T> extends MediatorLiveData<T> implements Callback<T> {


    private MutableLiveData<FailureResponse> failureLiveData;
    private MutableLiveData<Boolean> noNetworkLiveData;
    private MutableLiveData<Throwable> errorLiveData;

    private void initLiveData() {
        failureLiveData = new MutableLiveData<>();
        noNetworkLiveData = new MutableLiveData<>();
        errorLiveData = new MutableLiveData<>();
    }

    protected abstract Observer<Boolean> getNoNetworkObserver();

    protected abstract Observer<FailureResponse> getFailureObserver();

    protected abstract Observer<Throwable> getErrorObserver();

    @Override
    protected void onInactive() {
        super.onInactive();
        removeSource(failureLiveData);
        removeSource(noNetworkLiveData);
        removeSource(errorLiveData);
    }

    @Override
    protected void onActive() {
        super.onActive();
        initLiveData();
        addSource(failureLiveData, getFailureObserver());
        addSource(noNetworkLiveData, getNoNetworkObserver());
        addSource(errorLiveData, getErrorObserver());
    }

    @Override
    public void onResponse(Call<T> call, Response<T> response) {
        if (response.isSuccessful()) {
            setValue(response.body());
        } else {
            failureLiveData.setValue(getFailureErrorBody(call.request().url().url().getFile(), response));
        }
    }

    @Override
    public void onFailure(Call<T> call, Throwable t) {
        if (t instanceof SocketTimeoutException || t instanceof UnknownHostException) {
            noNetworkLiveData.setValue(true);
        } else {
            errorLiveData.setValue(t);
        }
    }

    /**
     * Create your custom failure response out of server response
     * Also save Url for any further use
     */
    protected final FailureResponse getFailureErrorBody(String url, Response<T> errorBody) {
        FailureResponse failureResponse = new FailureResponse();
        failureResponse.setErrorMessage(errorBody.message());
        failureResponse.setErrorCode(errorBody.code());
        return failureResponse;
    }
}