#vulnerable code 
                             @Override
	public void close() {

		if (!open.compareAndSet(true, false)) {
			return;
		}

		LOG.debug("Closing GStreamer device");

		image = null;

		LOG.debug("Unlink elements");

		pipe.setState(State.NULL);
		Element.unlinkMany(source, filter, sink);
		pipe.removeMany(source, filter, sink);
	} 
                            #location 16 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                             @Override
	public void close() {

		if (!open.compareAndSet(true, false)) {
			return;
		}

		LOG.debug("Closing GStreamer device");

		pipelineStop();

		image = null;
	}