private void ok() {
		String key = attributeField.getText();
		String value = valueField.getText();
		AttributeTableModel model = (AttributeTableModel) panel.getModel();
		
		// Validate Existence
		if ((key == null) || key.equals("")) {
			errorLabel.setText(ERROR_EXISTANCE);
			return;
		}
		
		// Validate alpha-numeric
		if (!XMLTools.isValidXMLAttributeName(key)) {
			errorLabel.setText(ERROR_ALPHA_NUMERIC);
			return;
		}
		
		// Validate Uniqueness
		for (int i = 0; i < model.keys.size(); i++) {
			String existingKey = (String) model.keys.get(i);
			if (key.equals(existingKey)) {
				errorLabel.setText(ERROR_UNIQUENESS);
				return;
			}
		}
		
		// All is good so lets make the change
		panel.newAttribute(key, value, false, model);
		panel.update(); // [md] Added so that modification date updates.
		
		this.hide();
	}