Bug 31374 Package Explorer does not show children of linked directories
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/StandardJavaElementContentProvider.java
try {
			
			Object[] members= folder.members();
			List nonJavaResources= new ArrayList();
			for (int i= 0; i < members.length; i++) {
				Object o= members[i];
				if (!(o instanceof IFolder && JavaCore.create((IFolder)o) != null)) {
					nonJavaResources.add(o);
				}	
			}
			return nonJavaResources.toArray();
		} catch(CoreException e) {
			return NO_CHILDREN;
		}
	}
	
	/**
	 * Note: This method is for internal use only. Clients should not call this method.
	 */
	protected boolean isClassPathChange(IJavaElementDelta delta) {
		int flags= delta.getFlags();
		return (delta.getKind() == IJavaElementDelta.CHANGED && 
			((flags & IJavaElementDelta.F_ADDED_TO_CLASSPATH) != 0) ||
			 ((flags & IJavaElementDelta.F_REMOVED_FROM_CLASSPATH) != 0) ||
			 ((flags & IJavaElementDelta.F_CLASSPATH_REORDER) != 0));
	}
	
	/**
	 * Note: This method is for internal use only. Clients should not call this method.
	 */