TreeSelectionListener() - one click two events!

Question

Hi, I am working with a JTree, when I click a leaf node it fires two events and so the code handling the event runs twice (this is not a double click just clicking on the leaf node). Obviously this not what I want and I do not want to have to build a 'memory' into the associated classes as this seems a bit messy. I am still working to resolve this issue for myself and have 'googled it'. If I resolve the issue I will post back but any help gratefully received......
Trevor
The associated code I am using is shown below:
//instantiation of the Tree:
jTreeSubjects = new javax.swing.JTree(rootNode);
jTreeSubjects.setEditable(true);
//setting selection model and attatching the listener:   
jTreeSubjects.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);
        jTreeSubjects.setShowsRootHandles(true);
        jTreeSubjects.addTreeSelectionListener(new TreeSelectionListener() {
            public void valueChanged(TreeSelectionEvent e) {
                jTreeSubjectsValueChanged(e);
//Handeling the events
private void jTreeSubjectsValueChanged(javax.swing.event.TreeSelectionEvent evt) {                                          
        DefaultMutableTreeNode node = (DefaultMutableTreeNode) jTreeSubjects.getLastSelectedPathComponent();
        if (node == null){
            return;
        RegionTreeNode nodeInfo = (RegionTreeNode) node.getUserObject();
        if (node.isLeaf()){
            RegionTreeNode RegionTreeNodeSelected = nodeInfo;
            System.err.println(RegionTreeNodeSelected.file.getAbsoluteFile());
        } else {
            return;
}

Answer 1

Just to explain
I added the code shown using the post creation code feature in netbeans, Prior to this I had added a handler for event valuechanged (jTreeSubjectsValueChanged). Hence one component two listners.