this.setLayout(new BorderLayout());
BeanDirectory root = CampaignClient.getInstance().getRootDirectory();
DocumentNode all = new DocumentNode(root, root.isDirectory());
MyTreeModel treeModel = new MyTreeModel(all);
tree = new JTree();
tree.setModel(treeModel);
tree.setRootVisible(false);
tree.getSelectionModel().setSelectionMode(
TreeSelectionModel.SINGLE_TREE_SELECTION);