final Button duplicateButton = new Button(buttongroup, SWT.PUSH);
duplicateButton.setText("Duplicate");
duplicateButton.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(final SelectionEvent event) {
Rule ruleToCopy = (Rule) tableViewer.getElementAt(table.getSelectionIndex());
model.copyRule(ruleToCopy);
updateRules();
updateBottomDisplay();