public Set getSet(int row, int column) {
		String s = (String) getValueAt(row, column);
		Set set = new TreeSet();
		for (int i = 0; i < s.length(); i++) {
			if (s.charAt(i) == '!') {
				set.add("");
				continue;
			}
			set.add(s.substring(i, i + 1));
		}
		return set;
	}