/** Listener to handle button actions */
 public void actionPerformed(ActionEvent e) {
   // Check if the user changed the service filter option
   if (e.getSource() == service_box) {
     service_list.setEnabled(service_box.isSelected());
     service_list.clearSelection();
     remove_service_button.setEnabled(false);
     add_service_field.setEnabled(service_box.isSelected());
     add_service_field.setText("");
     add_service_button.setEnabled(false);
   }
   // Check if the user pressed the add service button
   if ((e.getSource() == add_service_button) || (e.getSource() == add_service_field)) {
     String text = add_service_field.getText();
     if ((text != null) && (text.length() > 0)) {
       service_data.addElement(text);
       service_list.setListData(service_data);
     }
     add_service_field.setText("");
     add_service_field.requestFocus();
   }
   // Check if the user pressed the remove service button
   if (e.getSource() == remove_service_button) {
     Object[] sels = service_list.getSelectedValues();
     for (int i = 0; i < sels.length; i++) {
       service_data.removeElement(sels[i]);
     }
     service_list.setListData(service_data);
     service_list.clearSelection();
   }
 }
 /** Constructor */
 public ServiceFilterPanel(String text, Vector list) {
   empty_border = new EmptyBorder(5, 5, 0, 5);
   indent_border = new EmptyBorder(5, 25, 5, 5);
   service_box = new JCheckBox(text);
   service_box.addActionListener(this);
   service_data = new Vector();
   if (list != null) {
     service_box.setSelected(true);
     service_data = (Vector) list.clone();
   }
   service_list = new JList(service_data);
   service_list.setBorder(new EtchedBorder());
   service_list.setVisibleRowCount(5);
   service_list.addListSelectionListener(this);
   service_list.setEnabled(service_box.isSelected());
   service_scroll = new JScrollPane(service_list);
   service_scroll.setBorder(new EtchedBorder());
   remove_service_button = new JButton("Remove");
   remove_service_button.addActionListener(this);
   remove_service_button.setEnabled(false);
   remove_service_panel = new JPanel();
   remove_service_panel.setLayout(new FlowLayout());
   remove_service_panel.add(remove_service_button);
   service_area = new JPanel();
   service_area.setLayout(new BorderLayout());
   service_area.add(service_scroll, BorderLayout.CENTER);
   service_area.add(remove_service_panel, BorderLayout.EAST);
   service_area.setBorder(indent_border);
   add_service_field = new JTextField();
   add_service_field.addActionListener(this);
   add_service_field.getDocument().addDocumentListener(this);
   add_service_field.setEnabled(service_box.isSelected());
   add_service_button = new JButton("Add");
   add_service_button.addActionListener(this);
   add_service_button.setEnabled(false);
   add_service_panel = new JPanel();
   add_service_panel.setLayout(new BorderLayout());
   JPanel dummy = new JPanel();
   dummy.setBorder(empty_border);
   add_service_panel.add(dummy, BorderLayout.WEST);
   add_service_panel.add(add_service_button, BorderLayout.EAST);
   add_service_area = new JPanel();
   add_service_area.setLayout(new BorderLayout());
   add_service_area.add(add_service_field, BorderLayout.CENTER);
   add_service_area.add(add_service_panel, BorderLayout.EAST);
   add_service_area.setBorder(indent_border);
   setLayout(new BorderLayout());
   add(service_box, BorderLayout.NORTH);
   add(service_area, BorderLayout.CENTER);
   add(add_service_area, BorderLayout.SOUTH);
   setBorder(empty_border);
 }