Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.Dimension;
import java.awt.FlowLayout;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeExpansionEvent;
import javax.swing.event.TreeExpansionListener;
import javax.swing.event.TreeModelEvent;
import javax.swing.event.TreeModelListener;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreePath;
import javax.swing.tree.TreeSelectionModel;

public class Main {
    public static void main(String args[]) {
        JFrame f = new JFrame("JTree Demo");
        f.setSize(260, 240);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        DefaultMutableTreeNode root = new DefaultMutableTreeNode("Root");
        DefaultMutableTreeNode aNode = new DefaultMutableTreeNode("A");
        root.add(aNode);

        DefaultMutableTreeNode bNode = new DefaultMutableTreeNode("B");
        aNode.add(bNode);

        DefaultMutableTreeNode cNode = new DefaultMutableTreeNode("C");
        aNode.add(cNode);

        cNode.add(new DefaultMutableTreeNode("D"));
        cNode.add(new DefaultMutableTreeNode("E"));

        DefaultMutableTreeNode fNode = new DefaultMutableTreeNode("F");
        root.add(fNode);

        DefaultMutableTreeNode gNode = new DefaultMutableTreeNode("G");
        fNode.add(gNode);
        fNode.add(new DefaultMutableTreeNode("H"));
        gNode.add(new DefaultMutableTreeNode("I"));

        JTree jtree = new JTree(root);
        jtree.setEditable(true);

        TreeSelectionModel tsm = jtree.getSelectionModel();
        tsm.setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);

        jtree.addTreeExpansionListener(new TreeExpansionListener() {
            public void treeExpanded(TreeExpansionEvent tee) {
                TreePath tp = tee.getPath();
                System.out.println("Expansion: " + tp.getLastPathComponent());
            }

            public void treeCollapsed(TreeExpansionEvent tee) {
                TreePath tp = tee.getPath();
                System.out.println("Collapse: " + tp.getLastPathComponent());
            }
        });

        jtree.addTreeSelectionListener(new TreeSelectionListener() {
            public void valueChanged(TreeSelectionEvent tse) {
                TreePath tp = tse.getPath();
                System.out.println("Selection event: " + tp.getLastPathComponent());
            }
        });

        jtree.getModel().addTreeModelListener(new TreeModelListener() {
            public void treeNodesChanged(TreeModelEvent tme) {
                TreePath tp = tme.getTreePath();
                Object[] children = tme.getChildren();
                DefaultMutableTreeNode changedNode;
                if (children != null)
                    changedNode = (DefaultMutableTreeNode) children[0];
                else
                    changedNode = (DefaultMutableTreeNode) tp.getLastPathComponent();

                System.out.println("Model change path: " + tp + "New data: " + changedNode.getUserObject());

            }

            public void treeNodesInserted(TreeModelEvent tme) {
            }

            public void treeNodesRemoved(TreeModelEvent tme) {
            }

            public void treeStructureChanged(TreeModelEvent tme) {
            }
        });

        f.add(new JScrollPane(jtree));
        f.setVisible(true);
    }
}