final JIconButton downButton = new JIconButton("icons/001_22.png");
downButton.setPreferredSize(buttonDimension);
downButton.setMaximumSize(buttonDimension);
downButton.setMinimumSize(buttonDimension);
downButton.addActionListener(new ActionListener(){
@Override
public void actionPerformed(final ActionEvent e) {
UnitermOperatorPanel.this.unitermOperator.swapTerms(term,false);
UnitermOperatorPanel.this.repaintAllTerms();
}});