@Override
	public Exit getPairedExit(int direction)
	{
		final Exit opExit=getReverseExit(direction);
		final Exit myExit=getExitInDir(direction);
		if((myExit==null)||(opExit==null))
			return null;
		if(myExit.hasADoor()!=opExit.hasADoor())
			return null;
		return opExit;
	}