何时在应用程序范围内使用锁定

I am wondering if I need to lock some code created in the application scope. If I create an object say userDAO.cfc in application scope so its available to all pages. Then if I have a method in that object say getUserInfo(userID) that would be called in different parts of the applications, do I need to lock this method?I am wondering if I need to lock some code crea