code: public void stop() throws IllegalStateException {
          Log.d(TAG, "stop");
  
          if (mediaPlayer != null) {
              currentState = State.STOPPED;
              mediaPlayer.stop();
          } else throw new RuntimeException("Media Player is not initialized");
      }
docs: MediaPlayer method (stop)
  
  @see <a href="http://developer.android.com/reference/android/media/MediaPlayer.html#stop%28%29">stop</a>