JTree selection questions

Question

I am wanting a user to select multiple top level folders in the tree.
Do I simply have the user ctrl select multiple folders? Or is it possible to place a checkboxes next to the tree items?
If I have a button that trigger a function. How does that function know what items were selected in the tree?

Answer 1

http://java.sun.com/docs/books/tutorial/uiswing/events/treeexpansionlistener.html
OR
let the JPanel that contains the tree implement MouseListener
then
     public void mouseClicked(MouseEvent e) {
          // right-click?
          if (e.getButton() == MouseEvent.BUTTON3)
               return;
          int x = e.getX();
          int y = e.getY();
          TreePath selPath = tree.getClosestPathForLocation(x, y);
          if (selPath == null)
               return null;
          DefaultMutableTreeNode nodeClicked = (DefaultMutableTreeNode) selPath.getLastPathComponent();
          Rectangle rect = tree.getPathBounds(selPath);
if(rect.contains(x,y))
//you get the idea...
}