import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.tree.*;

public class ModifyTree extends JApplet {
  // Create a combo box for choosing selection modes
  private JComboBox jcboSelectionMode = new JComboBox(new String[]{
    "CONTIGUOUS_TREE_SELECTION", "DISCONTIGUOUS_TREE_SELECTION",
    "SINGLE_TREE_SELECTION"});

  // Create a check box for specifying editable
  private JCheckBox jchkEditable = new JCheckBox();

  // Create two buttons
  private JButton jbtAdd =
    new JButton("Add a Child for Selected Node");
  private JButton jbtRemove = new JButton("Remove Selected Nodes");

  // Declare two trees
  private JTree jTree1, jTree2;

  public ModifyTree() {
    // Create the first tree
    DefaultMutableTreeNode root, europe, northAmerica, us;

    europe = new DefaultMutableTreeNode("Europe");
    europe.add(new DefaultMutableTreeNode("UK"));
    europe.add(new DefaultMutableTreeNode("Germany"));
    europe.add(new DefaultMutableTreeNode("France"));
    europe.add(new DefaultMutableTreeNode("Norway"));

    northAmerica = new DefaultMutableTreeNode("North America");
    us = new DefaultMutableTreeNode("US");
    us.add(new DefaultMutableTreeNode("California"));
    us.add(new DefaultMutableTreeNode("Texas"));
    us.add(new DefaultMutableTreeNode("New York"));
    us.add(new DefaultMutableTreeNode("Florida"));
    us.add(new DefaultMutableTreeNode("Illinois"));
    northAmerica.add(us);
    northAmerica.add(new DefaultMutableTreeNode("Canada"));

    root = new DefaultMutableTreeNode("World");
    root.add(europe);
    root.add(northAmerica);

    jcboSelectionMode.setSelectedIndex(1);

    JPanel p1 = new JPanel();
    p1.add(new JLabel("selectionMode"));
    p1.add(jcboSelectionMode);
    p1.add(new JLabel("editable"));
    p1.add(jchkEditable);

    JPanel p2 = new JPanel(new GridLayout(1, 2));
    p2.add(new JScrollPane(jTree1 = new JTree(root)));
    p2.add(new JScrollPane(jTree2 =
      new JTree(new DefaultTreeModel(root)))); // Same root as jTree1

    JPanel p3 = new JPanel();
    p3.add(jbtAdd);
    p3.add(jbtRemove);

    add(p1, BorderLayout.NORTH);
    add(p2, BorderLayout.CENTER);
    add(p3, BorderLayout.SOUTH);

    // Register listeners
    jcboSelectionMode.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        if (jcboSelectionMode.getSelectedItem().
            equals("CONTIGUOUS_TREE_SELECTION"))
          jTree1.getSelectionModel().setSelectionMode(
            TreeSelectionModel.CONTIGUOUS_TREE_SELECTION);
        else if (jcboSelectionMode.getSelectedItem().
            equals("DISCONTIGUOUS_TREE_SELECTION"))
          jTree1.getSelectionModel().setSelectionMode(
            TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION);
        else
          jTree1.getSelectionModel().setSelectionMode(
            TreeSelectionModel.SINGLE_TREE_SELECTION);
      }
    });

    jchkEditable.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        jTree1.setEditable(jchkEditable.isSelected());
      }
    });

    jbtAdd.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        DefaultMutableTreeNode parent = (DefaultMutableTreeNode)
          jTree1.getLastSelectedPathComponent();

        if (parent == null) {
          JOptionPane.showMessageDialog(null,
            "No node in the left tree is selected");
          return;
        }

        // Enter a new node
        String nodeName = JOptionPane.showInputDialog(
          null, "Enter a child node for "+ parent, "Add a Child",
          JOptionPane.QUESTION_MESSAGE);

        // Insert the new node as a child of treeNode
        parent.add(new DefaultMutableTreeNode(nodeName));

        // Reload the model since a new tree node is added
        ((DefaultTreeModel)(jTree1.getModel())).reload();
        ((DefaultTreeModel)(jTree2.getModel())).reload();
      }
    });

    jbtRemove.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        // Get all selected paths
        TreePath[] paths = jTree1.getSelectionPaths();

        if (paths == null) {
          JOptionPane.showMessageDialog(null,
            "No node in the left tree is selected");
          return;
        }

        // Remove all selected nodes
        for (int i = 0; i < paths.length; i++) {
          DefaultMutableTreeNode node = (DefaultMutableTreeNode)
              (paths[i].getLastPathComponent());

          if (node.isRoot()) {
            JOptionPane.showMessageDialog(null,
              "Cannot remove the root");
          }
          else
            node.removeFromParent();
        }

        // Reload the model since a new tree node is added
        ((DefaultTreeModel)(jTree1.getModel())).reload();
        ((DefaultTreeModel)(jTree2.getModel())).reload();
      }
    });
  }

  public static void main(String[] args) {
    ModifyTree applet = new ModifyTree();
    JFrame frame = new JFrame();
    //EXIT_ON_CLOSE == 3
    frame.setDefaultCloseOperation(3);
    frame.setTitle("ModifyTree");
    frame.getContentPane().add(applet, BorderLayout.CENTER);
    applet.init();
    applet.start();
    frame.setSize(650, 320);
    Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);
  }
}