//中忙你写了个，看看吧
import java.awt.Color;
import javax.swing.*;
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.TreePath;

public class TestJTree implements TreeSelectionListener {
    JTree tree;
    DefaultMutableTreeNode root;
    DefaultTreeModel model;
    JSplitPane mainSplitpane;

    public TestJTree() {

        mainSplitpane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT); // 分割面板

        

        
        model = new DefaultTreeModel(root); // 设置树的缺省模式
        tree = new JTree(model);
        root = new DefaultMutableTreeNode("TestTree");//树根
        DefaultMutableTreeNode level1 = new DefaultMutableTreeNode("A");
        DefaultMutableTreeNode level2 = new DefaultMutableTreeNode("分支1"); // 树叶
        DefaultMutableTreeNode level3 = new DefaultMutableTreeNode("分支2");

        level1.add(level2);
        level1.add(level3);
        root.add(level1);

        tree = new JTree(root);

        DefaultTreeCellRenderer render = new DefaultTreeCellRenderer(); // 树叶
        render.setTextSelectionColor(Color.blue); // 选择时候的颜色
        render.setTextNonSelectionColor(Color.black); // 非选择时候颜色
        tree.setCellRenderer(render);
        tree.addTreeSelectionListener(this);

        
        JPanel firstimg = new JPanel();
        firstimg.setLayout(null);
        ImageIcon img = new ImageIcon("img/firstimg.jpg");
        JLabel imgLabel = new JLabel(img); // 面板，此处实际是一张图片
        imgLabel.setBounds(0, 0, img.getIconWidth(), img
                .getIconHeight());
        firstimg.add(imgLabel);
        
        mainSplitpane.setDividerLocation(185);
        mainSplitpane.setLeftComponent(tree);
        mainSplitpane.setRightComponent(firstimg);
        
        JFrame jf = new JFrame("TestTree");
        jf.setSize(900, 600);
        jf.setContentPane(mainSplitpane);
        jf.setLocationRelativeTo(null);
        jf.setVisible(true);
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        
    }

    public void valueChanged(TreeSelectionEvent e) {
        if (e.getSource() == tree) {
            DefaultMutableTreeNode node = (DefaultMutableTreeNode) tree
                    .getLastSelectedPathComponent();

            if (node.isLeaf()) {
                System.out.println(node.toString());
                TreePath visiblePath = new TreePath(model.getPathToRoot(node));
                System.out.println(visiblePath.toString());
                if (node.toString().equals("分支1")) {
                    //mainSplitpane.setRightComponent(...do what you want here...);   重点在这里
                }
            }
        }
    }

    public static void main(String[] args) {
        new TestJTree();

    }
}