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
if (expandedElements.length > 0) {
			IMemento expandedMem= memento.createChild(TAG_EXPANDED);
			for (int i= 0; i < expandedElements.length; i++) {
				IMemento elementMem= expandedMem.createChild(TAG_ELEMENT);
				
				Object o= expandedElements[i];
				if (o instanceof IJavaElement)
					elementMem.putString(TAG_PATH, ((IJavaElement) expandedElements[i]).getHandleIdentifier());
			}
		}
	}
	private void restoreFilterAndSorter() {
		fViewer.setSorter(new JavaElementSorter());
		if (fMemento != null)	
			fActionSet.restoreFilterAndSorterState(fMemento);
	}
	private void restoreUIState(IMemento memento) {
		restoreExpansionState(memento);
		restoreSelectionState(memento);
		
		
	}
	private void restoreLinkingEnabled(IMemento memento) {
		Integer val= memento.getInteger(PreferenceConstants.LINK_PACKAGES_TO_EDITOR);
		if (val != null) {
			fLinkingEnabled= val.intValue() != 0;
		}
	}
	protected void restoreScrollState(IMemento memento, Tree tree) {
		ScrollBar bar= tree.getVerticalBar();