I HATE JTREE UPDATES!!!

Question

I've tried everything I can think of, but the JTree never updates properly.
Here's an example of what's going on.
I have a JTree that uses Drag and Drop. I have 2 folders in the C:\ drive. They are C:\NewFolder1 and C:\NewFolder2
I open Windows Explorer and drag C:\NewFolder1 into my JTree, dropping it in C:\NewFolder2
Windows Explorer shows it now as C:\NewFolder2\NewFolder1, however my bastard JTree never changed. When I try to refresh the JTree, I can get the JTree to collapse itself, but when I re-expand it, it is the same old structure.
Below is the relevant portions of code... Any suggestions?
    // ------------------TREE CREATION--------  //
    DFM = new DefaultTreeModel( getRoot() ); //The Default Tree Model
    tree = new JTree( DFM );
    tree.setToggleClickCount(1);
    tree.setCellRenderer( new MyTreeRenderer() );
    tree.getSelectionModel().setSelectionMode( TreeSelectionModel.SINGLE_TREE_SELECTION ); //set single selection for the Tree
    tree.addTreeSelectionListener( new TreeSelectionListener()
      public void valueChanged( TreeSelectionEvent e )
        DefaultMutableTreeNode node = ( DefaultMutableTreeNode ) tree.getLastSelectedPathComponent();
        getChildren( node );
    scrollPane1.getViewport().add( tree, null );
// Should properly rebuild JTree //
  public void refreshTree()
    DFM.reload( getRoot() );     //getRoot() returns a DefaultMutableTreeNode
    //tree.setModel(DFM);
    //tree = new JTree(DFM);
    //scrollPane1.removeAll();
    //scrollPane1.getViewport().add( tree, null );
    scrollPane1.revalidate();
    scrollPane1.repaint();
  }

Answer 1

Below is my code...Maybe someone can spot something out of the ordinary?
package DND;
import jExplorer.DiskObject;
import javax.swing.*;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreePath;
import java.awt.*;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.dnd.*;
import java.io.File;
public class AutoscrollTree extends JTree implements Autoscroll, DragGestureListener, DragSourceListener
  private static final int AUTOSCROLL_MARGIN = 25;
  private Insets autoscrollInsets = new Insets( 0,0,0,0 );    // AutoScroll methods.
  private DefaultTreeModel dtModel;
  private DefaultMutableTreeNode root;
  public AutoscrollTree( DefaultMutableTreeNode root )
    super();
    this.root = root;
    dtModel = new DefaultTreeModel( root );
    setModel( dtModel );
    DragSource dragSource = DragSource.getDefaultDragSource();
    dragSource.createDefaultDragGestureRecognizer(
      this, // component where drag originates
      DnDConstants.ACTION_COPY_OR_MOVE, // actions
      this ); // drag gesture recognizer
    new DropTarget( this, getTargetListener() );
// AUTO SCROLLING //
  public void autoscroll( Point location )
  {        //System.out.println("mouse at " + location);
    int top = 0, left = 0, bottom = 0, right = 0;
    Dimension size = getSize();
    Rectangle rect = getVisibleRect();
    int bottomEdge = rect.y + rect.height;
    int rightEdge = rect.x + rect.width;
    if( location.y - rect.y <= AUTOSCROLL_MARGIN && rect.y > 0 ) top = AUTOSCROLL_MARGIN;
    if( location.x - rect.x <= AUTOSCROLL_MARGIN && rect.x > 0 ) left = AUTOSCROLL_MARGIN;
    if( bottomEdge - location.y <= AUTOSCROLL_MARGIN && bottomEdge < size.height ) bottom = AUTOSCROLL_MARGIN;
    if( rightEdge - location.x <= AUTOSCROLL_MARGIN && rightEdge < size.width ) right = AUTOSCROLL_MARGIN;
    rect.x += right - left;
    rect.y += bottom - top;
    scrollRectToVisible( rect );
  public Insets getAutoscrollInsets()
    Dimension size = getSize();
    Rectangle rect = getVisibleRect();
    autoscrollInsets.top = rect.y + AUTOSCROLL_MARGIN;
    autoscrollInsets.left = rect.x + AUTOSCROLL_MARGIN;
    autoscrollInsets.bottom = size.height - ( rect.y + rect.height ) + AUTOSCROLL_MARGIN;
    autoscrollInsets.right = size.width - ( rect.x + rect.width ) + AUTOSCROLL_MARGIN;
    return autoscrollInsets;
// Drag Listeners                                               //
  public void dragGestureRecognized( DragGestureEvent e )
    // drag anything ...
    String directory = getDirectory();
    e.startDrag( DragSource.DefaultCopyDrop, // cursor type
      new StringSelection( directory ),      // transferable
      this );                                // drag source listener
    System.out.println( "Start: " + directory );
  public void dragDropEnd( DragSourceDropEvent e )
    String directory = getDirectory();
    System.out.println( "End: " + directory );
  public void dragEnter( DragSourceDragEvent e )
    System.out.println( "Enter" );
  public void dragExit( DragSourceEvent e )
    System.out.println( "Exit" );
  public void dragOver( DragSourceDragEvent e )
    //  System.out.println( "Over" );
  public void dropActionChanged( DragSourceDragEvent e )
    System.out.println( "Action Changed" );
// DROP LISTENERS //
  public DropTargetListener getTargetListener()
    DropTargetListener dtl = new DropTargetAdapter()
      public void dragOver( DropTargetDragEvent dtde )
        int x = dtde.getLocation().x;
        int y = dtde.getLocation().y;
        TreePath path = getClosestPathForLocation( x, y );
        if( path != null )
          setSelectionPath( path );
      public void drop( DropTargetDropEvent dtde )
        try
// Ok, get the dropped object and try to figure out what it is.
          Transferable tr = dtde.getTransferable();
          DataFlavor[] flavors = tr.getTransferDataFlavors();
          for( int i = 0; i < flavors.length; i++ )
            System.out.println( "Possible flavor: " + flavors.getMimeType() );
// Check for file lists specifically.
if( flavors[i].isFlavorJavaFileListType() )
// Great! Accept copy drops...
dtde.acceptDrop( DnDConstants.ACTION_COPY );
System.out.println( "Successful file list drop.\n\n" );
// And add the list of file names to our text area
java.util.List list =
( java.util.List ) tr.getTransferData( flavors[i] );
// Destination directory
String directory = getDirectory();
File dir = new File( directory );
for( int j = 0; j < list.size(); j++ )
// Source File
File file = (File)list.get(j);
// Move file to new directory
boolean success = file.renameTo(new File(dir, file.getName()));
if (success)
System.out.println( "Moved "+list.get(j) + " to "+directory+"\n" );
else
System.out.println( "<ERROR>: Could not move "+list.get(j)+" to "+directory );
// If we made it this far, everything worked.
dtde.dropComplete( true );
// rebuild jtree
//if source folder still exists
// expand tree at source folder
// else expand tree at parent folder
// refresh table to match jtree
//refreshTree();
return;
// Hmm, the user must not have dropped a file list.
System.out.println( "Drop failed: " + dtde );
dtde.rejectDrop();
catch( Exception e )
e.printStackTrace();
dtde.rejectDrop();
return dtl;
// MISC FUNCTIONS //
public String getDirectory()
TreePath tp = getSelectionPath();
if( tp != null )
DefaultMutableTreeNode dmtn = ( DefaultMutableTreeNode ) tp.getLastPathComponent();
DiskObject dObj = ( DiskObject ) dmtn.getUserObject();
return dObj.getPath();
return null;
public void refreshTree()
System.out.println( "Refreshing Tree" );
dtModel.reload( root );
//dtModel.nodeChanged( root );
//dtModel.nodeStructureChanged( root() );
//setModel(dtModel);
//new AutoscrollTree(dtModel);