Drag and drop files

Question

Hello,
I've been working with Swing for a while now and it seems to work out perfectly well, only there is one thing I just don't understand. I have read numerous tutorials on this subject but wasn't able to find the current situation.
For example:
I have a JTable, populated with rows and columns. I want the user to be able to drag a row, to a folder somewhere on his computer, lets say desktop. I think the following needs to happen:
User begins dragging of the selected row
User drops it on the desktop
Desktop somehow magically returns the path where it was dropped
and some function, which I define, does the rest
What do I need to do in general to get this working?
Thanks

Answer 1

Ok, I have written the code with help of the tutorial, though, this is what I expected that would happen.
* ZFileTable.java
* Created: 14 may 2007
* Author: Lars 'Levia' Wesselius
* Description: The list for showing the files in the opened zip archive.
package Zipper;
import java.awt.*;
import java.io.*;
import java.util.*;
import java.awt.event.*;
import java.awt.dnd.*;
import java.awt.datatransfer.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;
public class ZFileTable extends JTable
                        implements DropTargetListener, DragSourceListener, DragGestureListener
    private ZControls m_Controls;
    DropTarget dropTarget = new DropTarget(this, this);
    DragSource dragSource = DragSource.getDefaultDragSource();
    public ZFileTable(DefaultTableModel model, ZControls controls)
        m_Controls = controls;
        dragSource.createDefaultDragGestureRecognizer(this, DnDConstants.ACTION_COPY_OR_MOVE, this);
        setModel(model);
    /* Method fired when something is dropped upon this table. */
    public synchronized void drop(DropTargetDropEvent dropTargetDropEvent)
        System.out.println("drop");
        try
            Transferable transferable = dropTargetDropEvent.getTransferable();
            if (transferable.isDataFlavorSupported(DataFlavor.javaFileListFlavor))
                dropTargetDropEvent.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
                java.util.List fileList = (java.util.List)transferable.getTransferData(DataFlavor.javaFileListFlavor);
                Iterator iterator = fileList.iterator();
                if (fileList.size() != 1)
                    dropTargetDropEvent.rejectDrop();
                    return;
                while (iterator.hasNext())
                    File file = (File)iterator.next();
                    m_Controls.doArchive(file.getCanonicalPath());
                dropTargetDropEvent.getDropTargetContext().dropComplete(true);
            else
                dropTargetDropEvent.rejectDrop();
        catch (IOException io)
        catch (UnsupportedFlavorException ufe)
    public void dragOver(DropTargetDragEvent dropTargetDragEvent)
        System.out.println("DragOver");
    public void dragExit(DropTargetEvent dropTargetEvent)
        System.out.println("DragExit");
    public void dropActionChanged(DropTargetDragEvent dropTargetDragEvent)
        System.out.println("DropActionChanged");
    public void dragEnter(DropTargetDragEvent dropTargetDragEvent)
        System.out.println("DragEnter");
        dropTargetDragEvent.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);       
    public void dragExit(DragSourceEvent dragSourceEvent)
        System.out.println("DragExit");
    public void dropActionChanged(DragSourceDragEvent dragSourceDragEvent)
        System.out.println("dropActionChanged");
    public void dragOver(DragSourceDragEvent dragSourceDragEvent)
        System.out.println("DragOver");
    public void dragDropEnd(DragSourceDropEvent dragSourceDropEvent)
        System.out.println("DragdropEnd");
    public void dragEnter(DragSourceDragEvent dragSourceDragEvent)
        System.out.println("DragEnter");
    public void dragGestureRecognized(DragGestureEvent dragGestureEvent)
        System.out.println("DragGestureRecognized");
        // Get the value we want to transfer
        String str = (String)getValueAt(getSelectedRow(), getSelectedColumn());
        // Check if the value is not null
        if (str != null)
            ZTransferable transferable = new ZTransferable(str);
            dragGestureEvent.startDrag(DragSource.DefaultCopyDrop, transferable, this);
    public Class getColumnClass(int column)
        return getValueAt(0, column).getClass();
    public boolean isCellEditable(int rowIndex, int vColIndex)
        return false;
}It currently accepts dropping and that works fine. Only when I drag an item from the table, and drop it on the desktop, I get an error..I suppose it should be changed and handled in the transferable. When I drag it into a text editor, I get to see the string, which is right, which comes from the transferable.
* ZTransferable.java
* Created: 14 may 2007
* Author: Lars 'Levia' Wesselius
* Description: This class is going to transfer data via DnD.
package Zipper;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.datatransfer.Transferable;
import java.awt.dnd.*;
import javax.swing.*;
import java.io.IOException;
import java.io.File;
import java.util.Vector;
class ZTransferable extends Vector implements Transferable
    DataFlavor flavors[] = {
                            DataFlavor.javaFileListFlavor,
                            DataFlavor.stringFlavor
    public ZTransferable(String str)
        addElement(str);
    public synchronized DataFlavor[] getTransferDataFlavors()
         return flavors;
    public boolean isDataFlavorSupported(DataFlavor flavor)
        boolean isSupported = false;
        isSupported |= flavor.equals(flavors[0]);
        isSupported |= flavor.equals(flavors[1]);
        return isSupported;
    public synchronized Object getTransferData(DataFlavor flavor)
                   throws UnsupportedFlavorException, IOException
        if (flavor.equals(flavors[0]))
             return this;
         else if (flavor.equals(flavors[1]))
            return elementAt(0);
        else
            throw new UnsupportedFlavorException(flavor);
}What do I need to change?