Bug 5699 Add ResourceTransfer to packages view
The packages view should add the ResoruceTransfer as a drag source to its list of transfers
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/dnd/JdtTreeViewerDropAdapter.java
private static final long HOVER_THRESHOLD= 1500;
	public JdtTreeViewerDropAdapter(AbstractTreeViewer viewer, int style) {
		super(viewer, style);
	}
	
	public void dragOver(DropTargetEvent event) {
		 
		
		Object oldTarget= fTarget;
		super.dragOver(event);
		if (oldTarget != fTarget) {
			hoverStart= System.currentTimeMillis();
		} else {
			
			if (hoverStart > 0 && (System.currentTimeMillis() - hoverStart) > HOVER_THRESHOLD) {
				expandSelection((TreeItem) event.item);
				hoverStart= 0;
			}
		}
	}
	
	private void expandSelection(TreeItem item) {
		if (item == null)
			return;
		Object element= item.getData();
		if (element == null)
			return;
		((AbstractTreeViewer)getViewer()).expandToLevel(element, 1);
	}
}