if (input instanceof List) return ((List)input).contains(element);
if (input instanceof Collection) return ((Collection)input).contains(element);
	protected boolean isValidElement(Object element) {		if (element == null)			return false;		element= getSuitableJavaElement(element);		if (element == null)			return false;		Object input= getViewer().getInput();		if (input == null)			return false;		if (input instanceof List)			return ((List)input).contains(element);		else			return input.equals(element);	}