Bug 31683 Show In doesn't work for class file in rt.jar
I20030611 - create Test project that uses Jar container - open NumberFormat.class - activate Show In... and choose Package Explorer Observe: NumberFormat.class doesn't get revealed.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
setProviders();
		
		JavaPlugin.getDefault().getPreferenceStore().addPropertyChangeListener(this);
	
		
		MenuManager menuMgr= new MenuManager("#PopupMenu"); 
		menuMgr.setRemoveAllWhenShown(true);
		menuMgr.addMenuListener(this);
		fContextMenu= menuMgr.createContextMenu(fViewer.getTree());
		fViewer.getTree().setMenu(fContextMenu);
		
		
		IWorkbenchPartSite site= getSite();
		site.registerContextMenu(menuMgr, fViewer);
		site.setSelectionProvider(fViewer);
		site.getPage().addPartListener(fPartListener);
		
		if (fMemento != null) {
			restoreLinkingEnabled(fMemento);
		}
		
		makeActions(); 
		
		
		restoreFilterAndSorter();
		fViewer.setInput(findInputElement());
		initDragAndDrop();
		initKeyListener();