Set tree DropMode to DropMode.USE_SELECTION : Drag Drop « Swing « Java Tutorial

import java.awt.BorderLayout;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.DropMode;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.JTree;
import javax.swing.TransferHandler;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreePath;

public class DndTree {
  public static void main(String args[]) {
    JFrame f = new JFrame();

    JPanel top = new JPanel(new BorderLayout());
    JLabel dragLabel = new JLabel("Drag me:");
    JTextField text = new JTextField();
    top.add(dragLabel, BorderLayout.WEST);
    top.add(text, BorderLayout.CENTER);
    f.add(top, BorderLayout.NORTH);

    final JTree tree = new JTree();
    final DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
    tree.setTransferHandler(new TransferHandler() {
      public boolean canImport(TransferHandler.TransferSupport support) {
        if (!support.isDataFlavorSupported(DataFlavor.stringFlavor) || !support.isDrop()) {
          return false;
        JTree.DropLocation dropLocation = (JTree.DropLocation) support.getDropLocation();
        return dropLocation.getPath() != null;

      public boolean importData(TransferHandler.TransferSupport support) {
        if (!canImport(support)) {
          return false;
        JTree.DropLocation dropLocation = (JTree.DropLocation) support.getDropLocation();
        TreePath path = dropLocation.getPath();
        Transferable transferable = support.getTransferable();

        String transferData;
        try {
          transferData = (String) transferable.getTransferData(DataFlavor.stringFlavor);
        } catch (IOException e) {
          return false;
        } catch (UnsupportedFlavorException e) {
          return false;

        int childIndex = dropLocation.getChildIndex();
        if (childIndex == -1) {
          childIndex = model.getChildCount(path.getLastPathComponent());

        DefaultMutableTreeNode newNode = new DefaultMutableTreeNode(transferData);
        DefaultMutableTreeNode parentNode = (DefaultMutableTreeNode) path.getLastPathComponent();
        model.insertNodeInto(newNode, parentNode, childIndex);

        TreePath newPath = path.pathByAddingChild(newNode);
        return true;

    JScrollPane pane = new JScrollPane(tree);
    f.add(pane, BorderLayout.CENTER);

    f.setSize(300, 400);

14.112.Drag Drop
14.112.1.Basic drag and drop
14.112.2.Dragging Text from a JLabelDragging Text from a JLabel
14.112.3.Drag-and-Drop Support for ImagesDrag-and-Drop Support for Images
14.112.4.Drag and drop icons: use an icon property.
14.112.5.implements DragGestureListener, Transferable
14.112.6.Dragging and dropping text between a text area, a list, and a tableDragging and dropping text between a text area, a list, and a table
14.112.7.Drag and drop between JTextArea and JTextField
14.112.8.Transfer both Text and Color between JTextField and JTextArea
14.112.9.Drag and drop between JList and JTextField
14.112.13.Set tree DropMode to DropMode.USE_SELECTION
14.112.14.Set tree drag mode to DropMode.ON
14.112.15.Set tree drag mode to DropMode.INSERT
14.112.16.Set tree drag mode to DropMode.ON_OR_INSERT
14.112.17.Choose Drop Action
14.112.18.Various drop actions
14.112.19.JTable drag and drop
14.112.20.Create a drag source a drop target and a transferable object.
14.112.21.Making a Component Draggable
14.112.22.Detect a drag initiating gesture in your application
14.112.23.Illustrates cut, copy, paste and drag and drop using three instances of JList
14.112.24.Location sensitive drag and drop
14.112.25.Demonstration of the top-level TransferHandler support on JFrame
14.112.26.Drag-and-Drop customization: drag the foreground color from the first label and drop it as the background color into the second one
14.112.27.Demonstrates how to add copy and drag support to a Swing component with TransferHandler
14.112.28.ScribblePane allows individual PolyLine lines to be selected, cut, copied, pasted, dragged, and dropped
14.112.29.Built-in drag and drop support: utilize a TransferHandler class
14.112.30.DND Drag and drop List