example of rxPlayer implementation

RxPlayer.java

package xD;

import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.media.MediaPlayer;
import android.util.Log;

import hugo.weaving.DebugLog;
import io.reactivex.Observable;
import io.reactivex.ObservableEmitter;
import io.reactivex.ObservableOnSubscribe;
import io.reactivex.disposables.Disposable;
import io.reactivex.functions.Cancellable;

/**
 * Project ***
 * <p>
 * Created by Lukasz Marczak
 * on 30.06.2017.
 */
public class RxPlayerMinimalistic {

    public static final String TAG = RxPlayerMinimalistic.class.getSimpleName();

    private Context context;

    public RxPlayerMinimalistic(Context context) {
        this.context = context;
    }

    public Observable<Boolean> play(final String path) {
        return Observable.create(new MediaPlayerObservableOnSubscribe(context, path));
    }

    public static class MediaPlayerObservableOnSubscribe 
            implements ObservableOnSubscribe<Boolean>, Cancellable {

        public static final String TAG = MediaPlayerObservableOnSubscribe.class.getSimpleName();

        MediaPlayer mediaPlayer;

        final String assetPath;
        final Context context;

        public MediaPlayerObservableOnSubscribe(Context context, String assetPath) {
            this.assetPath = assetPath;
            this.context = context;
        }

        @Override public void subscribe(final ObservableEmitter<Boolean> emitter) throws Exception {

            emitter.setCancellable(this);

            mediaPlayer = new MediaPlayer();
            mediaPlayer.reset();
            AssetFileDescriptor afd = context.getAssets().openFd(assetPath);
            mediaPlayer.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());
            afd.close();
            mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                @Override public void onPrepared(MediaPlayer mp) {
                    mp.start();
                    mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
                        @Override public void onCompletion(MediaPlayer mp) {
                            stopPlay(mp);
                            emitter.onNext(true);
                            emitter.onComplete();
                        }
                    });
                }
            });
            mediaPlayer.prepareAsync();
        }

        @Override public void cancel() throws Exception {
            stopPlay(mediaPlayer);
        }

        public boolean stopPlay(MediaPlayer mediaPlayer) {
            if (mediaPlayer == null) {
                return false;
            }

            mediaPlayer.setOnPreparedListener(null);
            mediaPlayer.setOnCompletionListener(null);

            try {
                mediaPlayer.stop();
            } catch (IllegalStateException ignored) {

            }
            try {
                mediaPlayer.reset();
            } catch (IllegalStateException ignored) {
            }
            try {
                mediaPlayer.release();
            } catch (IllegalStateException ignored) {
            }
            return true;
        }
    }
}