Bug 64880 Wrong rendering of unbound User library in package explorer [package explorer]
RC1 - create a user library for JUnit - now edit the .classpath file so that the class path entry points to a non existing library (e.g. <classpathentry kind="con" path="org.eclipse.jdt.USER_LIBRARY/JUnit2"/>) - save - the package explorer contain two JRE entries.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/ClassPathContainer.java
} catch (JavaModelException e) {
			fContainer= null;
		}
	}
	public boolean equals(Object obj) {
		if (obj instanceof ClassPathContainer) {
			ClassPathContainer other = (ClassPathContainer)obj;
			if (fProject.equals(other.fProject) &&
				fClassPathEntry.equals(other.fClassPathEntry)) {
				return true;	
			}
			
		}
		return false;
	}
	public int hashCode() {
		return fProject.hashCode()*17+fClassPathEntry.hashCode();
	}
	public Object[] getPackageFragmentRoots() {
		return fProject.findPackageFragmentRoots(fClassPathEntry);
	}
	public Object getAdapter(Class adapter) {
		if (adapter == IWorkbenchAdapter.class) 
			return this;
		if ((adapter == IResource.class) && (fContainer instanceof IAdaptable))
			return ((IAdaptable)fContainer).getAdapter(IResource.class);
		return null;
	}
	public Object[] getChildren(Object o) {
		return concatenate(getPackageFragmentRoots(), getRequiredProjects());