output: #fixed code
                               @Override
  	public void close() {
  
  		if (!open.compareAndSet(true, false)) {
  			return;
  		}
  
  		LOG.debug("Closing GStreamer device");
  
  		pipelineStop();
  
  		image = null;
  	}
input: #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