一、建立滾動條容器，將該容器新增到當前框架。（因為樹模型需要在滾動條中才能顯示完全）

JScrollPane scrollPane = new JScrollPane(); 

二、建立樹模型

JTree tree = new JTree(); 

DefaultMutableTreeNode dft =new DefaultMutableTreeNode("Jtree") {
   {
    DefaultMutableTreeNode node_1;
    node_1 = new DefaultMutableTreeNode("colors");
     node_1.add(new DefaultMutableTreeNode("blue"));
     node_1.add(new DefaultMutableTreeNode("violet"));
     node_1.add(new DefaultMutableTreeNode("red"));
     node_1.add(new DefaultMutableTreeNode("yellow"));
    add(node_1);
    node_1 = new DefaultMutableTreeNode("sports");
     node_1.add(new DefaultMutableTreeNode("basketball"));
     node_1.add(new DefaultMutableTreeNode("soccer"));
     node_1.add(new DefaultMutableTreeNode("football"));
     node_1.add(new DefaultMutableTreeNode("hockey"));
    add(node_1);
    node_1 = new DefaultMutableTreeNode("food");
     node_1.add(new DefaultMutableTreeNode("hot dogs"));
     node_1.add(new DefaultMutableTreeNode("pizza"));
     node_1.add(new DefaultMutableTreeNode("ravioli"));
     node_1.add(new DefaultMutableTreeNode("bananas"));
    add(node_1);
   }
  };

DefaultTreeModel dem =new DefaultTreeModel(dft);
  tree.setModel(dem);

三、將tree加入滾動條

scrollPane.setViewportView(tree);

完成之後是該模型

實現監聽就需要進行如下操作：

為Tree的物件新增addTreeSelectionListener事件監聽，通過node.toString()獲取節點名，具體程式碼：

tree.addTreeSelectionListener(new TreeSelectionListener() {
   public void valueChanged(TreeSelectionEvent e) {
    DefaultMutableTreeNode node = (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
    if (node == null) {
     return;
    }
    if (node.toString().equals("colors")) {
     JOptionPane.showMessageDialog(contentPane, "點中了cloors節點", "OK", JOptionPane.INFORMATION_MESSAGE);
    }
   }
  });

結果：