Hi....My question is In a JTree i want to add nodes to only the nodes whose parent is root node.Please help me with this.In the following code it should be possible to add node to "Medieval" but not "socrates.import java.awt.BorderLayout;import java.awt.Container;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTree;import javax.swing.tree.DefaultMutableTreeNode;import javax.swing.tree.DefaultTreeModel;public class ModelJTree extends JFrame { private JTree tree; private DefaultTreeModel model; private DefaultMutableTreeNode rootNode,Medievel,Ancient,Philosophers; public ModelJTree() { DefaultMutableTreeNode philosophersNode = getPhilosopherTree(); model = new DefaultTreeModel(philosophersNode); tree = new JTree(model); JButton addButton = new JButton("Add Philosopher"); addButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent event) { addPhilosopher(); } }); JButton removeButton = new JButton("Remove Selected Philosopher"); removeButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent event) { removeSelectedPhilosopher(); } }); JPanel inputPanel = new JPanel(); inputPanel.add(addButton); inputPanel.add(removeButton); Container container = getContentPane(); container.add(new JScrollPane(tree), BorderLayout.CENTER); container.add(inputPanel, BorderLayout.SOUTH); setDefaultCloseOperation(EXIT_ON_CLOSE); setSize(400, 300); setVisible(true); } private void addPhilosopher() { DefaultMutableTreeNode parent = getSelectedNode(); System.out.println(parent); if (parent == null) { JOptionPane.showMessageDialog(ModelJTree.this, "Select an area.", "Error", JOptionPane.ERROR_MESSAGE); return; } String name = JOptionPane.showInputDialog(ModelJTree.this, "Enter Name:"); model.insertNodeInto(new DefaultMutableTreeNode(name), parent, parent.getChildCount()); } private void removeSelectedPhilosopher() { DefaultMutableTreeNode selectedNode = getSelectedNode(); if (selectedNode != null) model.removeNodeFromParent(selectedNode); } private DefaultMutableTreeNode getSelectedNode() { return (DefaultMutableTreeNode) tree.getLastSelectedPathComponent(); } private DefaultMutableTreeNode getPhilosopherTree() { DefaultMutableTreeNode rootNode = new DefaultMutableTreeNode("Philosophers"); DefaultMutableTreeNode ancient = new DefaultMutableTreeNode("Ancient"); rootNode.add(ancient); ancient.add(new DefaultMutableTreeNode("Socrates")); DefaultMutableTreeNode medieval = new DefaultMutableTreeNode("Medieval",true); rootNode.add(medieval); return rootNode; } public static void main(String args[]) { new ModelJTree(); }}