public final synchronized void shutdownEngine(){
  if (uciEngine != null) {
    engineMonitor.interrupt();
    engineMonitor=null;
    uciEngine.shutDown();
    uciEngine=null;
  }
  engineState.setState(MainState.DEAD);
}

public final synchronized void shutdownEngine ( ) { if ( uciEngine != null ) { engineMonitor . interrupt ( ) ; engineMonitor = null ; uciEngine . shutDown ( ) ; uciEngine = null ; } engineState . setState ( MainState . DEAD ) ; }
stop the engine process .
