EditableTree.java Source code

Introduction

Here is the source code for EditableTree.java

Source

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Enumeration;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.MutableTreeNode;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;

public class EditableTree extends JFrame {

    private DefaultMutableTreeNode m_rootNode = new DefaultMutableTreeNode("AA");

    private DefaultTreeModel m_model = new DefaultTreeModel(m_rootNode);

    private JTree m_tree = new JTree(m_model);

    private JButton m_addButton = new JButton("Add Node");

    private JButton m_delButton = new JButton("Delete Node");

    private JButton m_searchButton = new JButton("Search Node");

    private JButton m_searchAndDeleteButton = new JButton("Search and Delete Node");

    private JTextField m_searchText;

    public EditableTree() {
        DefaultMutableTreeNode forums = new DefaultMutableTreeNode("A");
        forums.add(new DefaultMutableTreeNode("B"));
        DefaultMutableTreeNode articles = new DefaultMutableTreeNode("E");
        articles.add(new DefaultMutableTreeNode("F"));
        DefaultMutableTreeNode examples = new DefaultMutableTreeNode("G");
        examples.add(new DefaultMutableTreeNode("H"));

        m_rootNode.add(forums);
        m_rootNode.add(articles);
        m_rootNode.add(examples);

        m_tree.setEditable(true);
        m_tree.setSelectionRow(0);

        JScrollPane scrollPane = new JScrollPane(m_tree);
        getContentPane().add(scrollPane, BorderLayout.CENTER);

        JPanel panel = new JPanel();

        m_addButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                DefaultMutableTreeNode selNode = (DefaultMutableTreeNode) m_tree.getLastSelectedPathComponent();
                if (selNode == null) {
                    return;
                }
                DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("New Node");
                m_model.insertNodeInto(newNode, selNode, selNode.getChildCount());

                TreeNode[] nodes = m_model.getPathToRoot(newNode);
                TreePath path = new TreePath(nodes);
                m_tree.scrollPathToVisible(path);
                m_tree.setSelectionPath(path);
                m_tree.startEditingAtPath(path);
            }
        });
        panel.add(m_addButton);

        m_delButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                DefaultMutableTreeNode selNode = (DefaultMutableTreeNode) m_tree.getLastSelectedPathComponent();
                removeNode(selNode);
            }
        });
        panel.add(m_delButton);

        JPanel searchPanel = new JPanel();
        searchPanel.setBorder(BorderFactory.createEtchedBorder());

        m_searchText = new JTextField(10);
        searchPanel.add(m_searchText);

        m_searchButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                DefaultMutableTreeNode node = searchNode(m_searchText.getText());
                if (node != null) {
                    TreeNode[] nodes = m_model.getPathToRoot(node);
                    TreePath path = new TreePath(nodes);
                    m_tree.scrollPathToVisible(path);
                    m_tree.setSelectionPath(path);
                } else {
                    System.out.println("Node with string " + m_searchText.getText() + " not found");
                }
            }
        });
        searchPanel.add(m_searchButton);

        m_searchAndDeleteButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                DefaultMutableTreeNode node = searchNode(m_searchText.getText());
                if (node != null) {
                    removeNode(node);
                } else {
                    System.out.println("Node with string " + m_searchText.getText() + " not found");
                }
            }
        });
        searchPanel.add(m_searchAndDeleteButton);
        panel.add(searchPanel);
        getContentPane().add(panel, BorderLayout.SOUTH);
        setSize(700, 400);
        setVisible(true);
    }

    public DefaultMutableTreeNode searchNode(String nodeStr) {
        DefaultMutableTreeNode node = null;
        Enumeration e = m_rootNode.breadthFirstEnumeration();
        while (e.hasMoreElements()) {
            node = (DefaultMutableTreeNode) e.nextElement();
            if (nodeStr.equals(node.getUserObject().toString())) {
                return node;
            }
        }
        return null;
    }

    public void removeNode(DefaultMutableTreeNode selNode) {
        if (selNode == null) {
            return;
        }
        MutableTreeNode parent = (MutableTreeNode) (selNode.getParent());
        if (parent == null) {
            return;
        }
        MutableTreeNode toBeSelNode = getSibling(selNode);
        if (toBeSelNode == null) {
            toBeSelNode = parent;
        }
        TreeNode[] nodes = m_model.getPathToRoot(toBeSelNode);
        TreePath path = new TreePath(nodes);
        m_tree.scrollPathToVisible(path);
        m_tree.setSelectionPath(path);
        m_model.removeNodeFromParent(selNode);
    }

    private MutableTreeNode getSibling(DefaultMutableTreeNode selNode) {
        MutableTreeNode sibling = (MutableTreeNode) selNode.getPreviousSibling();
        if (sibling == null) {
            sibling = (MutableTreeNode) selNode.getNextSibling();
        }
        return sibling;
    }

    public static void main(String[] arg) {
        EditableTree editableTree = new EditableTree();
    }
}