public void keyTyped(KeyEvent event) {
		if (viewType == MULTI_TEXTFIELD_VIEW) {
			char typed = event.getKeyChar();
			if (! Character.isDigit(typed))
				event.consume();
			else if (event.getSource() != yearField) {
				JTextField field = (JTextField) event.getSource();
				String text = field.getText();
				if (text.length() == 2 && (field.getSelectedText() == null || field.getSelectedText().length() != 2))
					event.consume();
			} else {
				String text = yearField.getText();
				if (text.length() == 4 && (yearField.getSelectedText() == null || yearField.getSelectedText().length() != 4))
					event.consume();
			}
		}
	}