Bug 15301 'show in packages view' - does not work fo java files not in source folders
20020502 open a java file that is in a resource folder (so it is not an ICompilationUnit - just a file with .java extension) 'show in packages view' is present in the context menu but it does nothing
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
private void initDragAndDrop() {
		int ops= DND.DROP_COPY | DND.DROP_MOVE | DND.DROP_LINK;
		final LocalSelectionTransfer lt= LocalSelectionTransfer.getInstance();
		Transfer[] transfers= new Transfer[] {
			lt, 
			ResourceTransfer.getInstance(),
			FileTransfer.getInstance()};
		
		
		TransferDropTargetListener[] dropListeners= new TransferDropTargetListener[] {
			new SelectionTransferDropAdapter(fViewer),
			new FileTransferDropAdapter(fViewer)
		};
		fViewer.addDropSupport(ops, transfers, new DelegatingDropAdapter(dropListeners));
		
		
		Control control= fViewer.getControl();
		TransferDragSourceListener[] dragListeners= new TransferDragSourceListener[] {
			new SelectionTransferDragAdapter(fViewer),
			new ResourceTransferDragAdapter(fViewer),
			new FileTransferDragAdapter(fViewer)
		};
		DragSource source= new DragSource(control, ops);
		
		source.addDragListener(new DelegatingDragAdapter(dragListeners) {
			public void dragStart(DragSourceEvent event) {
				IStructuredSelection selection= (IStructuredSelection)getSelection();
				for (Iterator iter= selection.iterator(); iter.hasNext(); ) {