@Override
	public String toString() {
		StringBuilder s = new StringBuilder();
		s.append("  A B C D E F G H\n");
		for (int r=0; r<size; r++) {
			s.append(r+1);
			s.append(' ');
			for (int c=0; c<size; c++) {
				if (board.getCell(r, c) != null) {
					switch (board.getCell(r, c)) {
						case BLACK_PIECE : s.append('x'); break;
						case BLACK_QUEEN : s.append('X'); break;
						case WHITE_QUEEN : s.append('Q'); break;
						case WHITE_PIECE : s.append('o'); break;
					}					
				} else {
					s.append('.');
				}
				s.append(' ');
			}
			s.append('\n');
		}		
		
		return s.toString();
	}