private DefaultMutableTreeNode root = new DefaultMutableTreeNode("根节点");

private DefaultTreeModel treeModel = new DefaultTreeModel(root);

private JTree tree = new JTree(treeModel);

DefaultMutableTreeNode node = new DefaultMutableTreeNode("一级节点");DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("二级节点");/*方法：insertNodeInto(DefaultMutableTreeNode child, DefaultMutableTreeNode parent, int index)形参：child  所要插入的节点形参：parent 插入节点的上级节点形参: index  插入节点在父节点下的位置*/treeModel.insertNodeInto(node, root, root.getChildCount());treeModel.insertNodeInto(node2, node, node.getChildCount());

tree.addTreeSelectionListener(new TreeSelectionListener(){       public void valueChanged(TreeSelectionEvent e){           //监听器操作代码       }});

JFrame jf = new JFrame("树形结构");jf.add(tree);jf.setVisiable(true);

//获取树节点渲染器DefaultTreeCellRenderer cellRenderer = tree.getCellRenderer();//设置未选择时为黑色cellRenderer.setTextNonSelectionColor(Color.black);//设置选择时为蓝色cellRenderer.setTextSelectionColor(Color.blue);//设置选择模式只能选择一个tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);

package test;import java.awt.Color;import java.awt.Dimension;import java.awt.Toolkit;import javax.swing.JFrame;import javax.swing.JTree;import javax.swing.event.TreeSelectionEvent;import javax.swing.event.TreeSelectionListener;import javax.swing.tree.DefaultMutableTreeNode;import javax.swing.tree.DefaultTreeCellRenderer;import javax.swing.tree.DefaultTreeModel;import javax.swing.tree.TreeSelectionModel;@SuppressWarnings("serial")public class Test extends JFrame implements TreeSelectionListener{    private DefaultMutableTreeNode root, node_1, node_2;    private DefaultTreeModel treeModel;    private JTree tree;    public Test(){        this.setSize(200, 150);        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();        int x = (screenSize.width - this.getSize().width)/2;        int y = (screenSize.height - this.getSize().height)/2;        this.setLocation(x, y);                root = new DefaultMutableTreeNode("根节点");        node_1 = new DefaultMutableTreeNode("一级");        node_2 = new DefaultMutableTreeNode("二级");                treeModel = new DefaultTreeModel(root);        treeModel.insertNodeInto(node_1, root, root.getChildCount());        treeModel.insertNodeInto(node_2, node_1, node_1.getChildCount());                tree = new JTree(treeModel);        tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);                DefaultTreeCellRenderer cellRenderer = (DefaultTreeCellRenderer)tree.getCellRenderer();        cellRenderer.setTextNonSelectionColor(Color.black);        cellRenderer.setTextSelectionColor(Color.blue);                this.add(tree);        this.setVisible(true);    }    public void valueChanged(TreeSelectionEvent e) {            }    public static void main(String[] args){        @SuppressWarnings("unused")        Test test = new Test();    }    }