remove.setEnabled(index != -1);
remove.setEnabled(index != -1 && errorListModel.getSize() != 0);
	private void updateButtons()	{		int index = list.getSelectedIndex();		remove.setEnabled(index != -1);		moveUp.setEnabled(index > 0);		moveDown.setEnabled(index != -1 && index != listModel.getSize() - 1);	}