Trees - The Definitive Guide to Java Swing - page 662

Figure 17-20. TreePath sample tree
Using Figure 17-20 to visualize a tree starting from its root, the TreePath for the Jets node
would be described by its properties as follows:
• lastPathComponent : A DefaultMutableTreeNode whose user object is Jets .
• parentPath : A TreePath made up of the root , New York , and Football nodes.
• path : An array of DefaultMutableTreeNode nodes whose user objects are root , New York ,
Football , and Jets .
• pathCount : 4.
That's really all there is to the TreePath class. Just remember that you can't change an
existing TreePath —you can only access its elements.
Additional Expansion Events
Two listeners that can be registered with a JTree have yet to be discussed: a
TreeExpansionListener and a TreeWillExpandListener .
TreeExpansionListener Interface and TreeExpansionEvent Class
If you're interested in finding out when a tree node has been expanded or collapsed, you can
register a TreeExpansionListener with a JTree . Any registered listener will be notified after the
expansion or collapse of a parent node.
public interface TreeExpansionListener implements EventListener {
public void treeCollapse(TreeExpansionEvent treeExpansionEvent);
public void treeExpand(TreeExpansionEvent treeExpansionEvent);
}