public void destroy(){
  if (keyRotationExecutor != null) {
    keyRotationExecutor.shutdown();
    _log.debug("Shutting down key rotation thread");
  }
}

public void destroy ( ) { if ( keyRotationExecutor != null ) { keyRotationExecutor . shutdown ( ) ; _log . debug ( "Shutting down key rotation thread" ) ; } }
terminates scheduled threads executor
