D&D problem since SDK1.4. Dropped object falls through JPanel

Question

Hi,
my application consists of two JInternalFrame.
First frame consists of JTree and JPanel.
Second frame consists of JTextArea.
JTree is DragSource, JTextArea is DropTarget. JPanel-object is neither DragSource, nor DropTarget.
It is possible to drag tree nodes from the JTree and to drop into the JTextArea.
Drag & drop from the JTree into JPanel does not work - as expected.
But it still possible to provide "drag & drop", even if the JTextArea is covered(partly or --completely) byJPanel. That means,that the dropped node "falls" through  the JPanel on the underlying JTextArea.
This phenomenon occurs only since jdk 1.4.
How can I prevent my application from such a behaviour?
Thanks,
Sergey35
import javax.swing.*;
import java.awt.dnd.*;
import java.awt.datatransfer.*;
public class TestDnD extends JFrame implements DragGestureListener,
DragSourceListener,
DropTargetListener
JTree tree = new JTree();
JPanel panel = new JPanel();
JTextArea text = new JTextArea();
JDesktopPane desktop = new JDesktopPane();
JInternalFrame frameFirst = new JInternalFrame("First",true,true,true,true);
JInternalFrame frameSecond = new JInternalFrame("Second",true,true,true,true);
JSplitPane split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,tree,panel);
public TestDnD()
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.getContentPane().add(desktop);
this.setSize(400,400);
this.setVisible(true);
desktop.add(frameSecond);
desktop.add(frameFirst);
frameFirst.getContentPane().add(split);
frameSecond.getContentPane().add(text);
frameFirst.setBounds(0,0,200,200);
frameSecond.setBounds(100,100,200,200);
frameSecond.setVisible(true);
frameFirst.setVisible(true);
DragSource dragSource = DragSource.getDefaultDragSource();
dragSource.createDefaultDragGestureRecognizer(tree,
DnDConstants.ACTION_COPY_OR_MOVE,
this);
new DropTarget(text, DnDConstants.ACTION_COPY_OR_MOVE,
this);
public void dragGestureRecognized(DragGestureEvent e)
Object o =tree.getLastSelectedPathComponent();
StringSelection transObject=new StringSelection(o.toString());
try
e.startDrag(DragSource.DefaultMoveDrop, // cursor
null, // Image image
null, // Point offset
transObject,
this); // drag source listener
catch(InvalidDnDOperationException dnd)
dnd.printStackTrace();
/** DragSourceListener implementation.*/
public void dragDropEnd(DragSourceDropEvent e){ }
public void dragEnter(DragSourceDragEvent e) { }
public void dragExit(DragSourceEvent e){ }
public void dragOver(DragSourceDragEvent e) { }
public void dropActionChanged(DragSourceDragEvent e) { }
/** Implementation of DropTargetListener. */
public void drop(DropTargetDropEvent e)
try
Transferable tr = e.getTransferable();
if(e.isDataFlavorSupported(DataFlavor.stringFlavor))
String string = (String)tr.getTransferData(DataFlavor.stringFlavor);
e.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
e.dropComplete(true);
text.setText(string);
else
e.rejectDrop();
catch(Exception ex)
ex.printStackTrace();
}// End drop
/** Implementation of DropTargetListener. */
public void dragOver(DropTargetDragEvent e)
System.out.print(".");
public void dropActionChanged(DropTargetDragEvent e) { }
public void dragEnter(DropTargetDragEvent e) {   }
public void dragExit(DropTargetEvent e) {   }
public static void main(String[] arg)
try
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
catch(Exception e){  }
new TestDnD();

Answer 1

Drag & drop has changed dramaticaly for jdk1.4, the methods you use are obsolete now. Check out the differences: http://java.sun.com/j2se/1.4.1/docs/guide/swing/1.4/dnd.html