setBorder(BorderFactory.createLineBorder(Color.BLACK));
  protected void configurePopup()  {    // initialize list that will be used to display combo box's items    this.list = createList();    ((JLabel) list.getCellRenderer()).setHorizontalAlignment(SwingConstants.LEFT);    configureList();    // initialize scroller. Add list to the scroller.	    scroller = createScroller();    configureScroller();    // add scroller with list inside of it to JPopupMenu    super.add(scroller);  }