## 模型封装(用的最多) action:实现ModelDriven接口,传入要封装的对象.实现getModel方法.创建私有属性并实例化. ~~~ public class HelloAction extends ActionSupport implements ModelDriven<User> { private User user = new User(); @Override public User getModel() { return user; } public String index() { System.out.println(user); return null; } } ~~~