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/PackageExplorerContentProvider.java
} else {
				result.add(roots[i]);
			}
		}
		for (Iterator each= containers.iterator(); each.hasNext();) {
			IClasspathEntry element= (IClasspathEntry) each.next();
			result.add(new ClassPathContainer(project, element));
		}		
		return result.toArray();
	}
	private Object[] getContainerPackageFragmentRoots(ClassPathContainer container) throws JavaModelException {
		return container.getPackageFragmentRoots();
	}
	private Object[] getNonJavaProjects(IJavaModel model) throws JavaModelException {
		return model.getNonJavaResources();
	}
	public Object getParent(Object child) {
		if (needsToDelegateGetParent(child)) {
			return fPackageFragmentProvider.getParent(child);
		} else
			return super.getParent(child);
	}
	private boolean needsToDelegateGetParent(Object element) {
		int type= -1;
		if (element instanceof IJavaElement)
			type= ((IJavaElement)element).getElementType();
		return (!fIsFlatLayout && type == IJavaElement.PACKAGE_FRAGMENT);
	}		
	/**
	 * Returns the given objects with the resources of the parent.