@Override
	public Object getValueAt(int rowIndex, int columnIndex) {

		if (columnIndex < 0 || columnIndex >= COL_NAMES.length || rowIndex < 0
				|| rowIndex >= propNames.length) {
			return null;
		}

		if (columnIndex == 0) {
			return propNames[rowIndex];
		}

		if (columnIndex == 1) {
			return props.get(propNames[rowIndex]);
		}

		return null;
	}