private boolean has6Neighbors(PieceCoordinate butterflyPos) {
		int neighbors = 0;
		
		Iterator<Entry<PieceCoordinate, HantoPiece>> pieces = board.entrySet().iterator();
		PieceCoordinate next;
		while(pieces.hasNext()) {
			Entry<PieceCoordinate, HantoPiece> entry = pieces.next();
			next = entry.getKey();
			if (next.isAdjacentTo(butterflyPos)) neighbors++;
		}
		
		return neighbors == 6;
	}