if (context.get() == null) return null; LinkedList ll = (LinkedList) context.get(); return ll.size()>0 ? ll.getLast() : null;
return _context.size()>0 ? _context.getLast() : null;
    public Object currentContext(){        if (context.get() == null) return null;        LinkedList ll = (LinkedList) context.get();        return ll.size()>0 ? ll.getLast() : null;    }