public boolean isAdjacentTo(HantoCoordinate otherCoordinate) {
		if (otherCoordinate.equals(this)) return false;

		int otherX = otherCoordinate.getX();
		int otherY = otherCoordinate.getY();

		int deltaX = otherX - x;
		int deltaY = otherY - y;
		
		if (deltaX < 0 && deltaY < 0 || deltaX > 0 && deltaY > 0) return false; 

		boolean xAdjacent = Math.abs(deltaX) < 2; 
		boolean yAdjacent = Math.abs(deltaY) < 2;

		return (xAdjacent && yAdjacent); 
	}