CallWebService.java

import android.util.Log;

import androidx.annotation.MainThread;
import androidx.annotation.NonNull;
import androidx.annotation.WorkerThread;

import com.google.gson.JsonObject;
import com.google.gson.stream.MalformedJsonException;

import java.io.IOException;
import java.net.SocketTimeoutException;

import io.reactivex.Observable;
import io.reactivex.Observer;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.disposables.Disposable;
import io.reactivex.schedulers.Schedulers;
import khaneEghtesad.manym.Constants;
import khaneEghtesad.manym.R;
import khaneEghtesad.manym.app.base.AppController;
import retrofit2.HttpException;


/**
 * Author: Hamed Taherpour
 * *
 * Created: 10/8/2019
 */
public abstract class CallWebService<T> {

    private JsonObject jsonObject;

    @MainThread
    protected CallWebService() {
        jsonObject = new JsonObject();
        onResponseLoading();
        fetchFromNetwork();
    }

    private void fetchFromNetwork() {
        String json = getParameter(jsonObject).toString();
        createCall(json).subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Observer<T>() {
                    @Override
                    public void onSubscribe(Disposable d) {

                    }

                    @Override
                    public void onNext(T response) {
                        onResponseResult(response);
                    }

                    @Override
                    public void onError(Throwable e) {
                        String message = getCustomErrorMessage(e);
                        onResponseError(message);
                        Log.i(Constants.TAG, "Error: WebService -> " + message);
                        onResponseDone();
                    }

                    @Override
                    public void onComplete() {
                        onResponseDone();
                    }
                });
    }

    private String getCustomErrorMessage(Throwable error) {
        if (error instanceof SocketTimeoutException) {
            return AppController.getAppContext().getString(R.string.requestTimeOutError);
        } else if (error instanceof MalformedJsonException) {
            return AppController.getAppContext().getString(R.string.responseMalformedJson);
        } else if (error instanceof IOException) {
            return AppController.getAppContext().getString(R.string.networkError);
        } else if (error instanceof HttpException) {
            return (((HttpException) error).response().message());
        } else {
            return AppController.getAppContext().getString(R.string.unknownError);
        }
    }

    @WorkerThread
    protected abstract void onResponseResult(T data);

    protected abstract void onResponseLoading();

    protected abstract void onResponseError(String message);

    protected abstract void onResponseDone();

    @MainThread
    protected abstract JsonObject getParameter(JsonObject jsonObject);

    @NonNull
    @MainThread
    protected abstract Observable<T> createCall(String json);
}