ActionContext(用new ThreadLocal()邦定了线程)

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 　　　　  |--ServletActionContext

public class ContextAction extends ActionSupport {                        public String test(){                                //获取request对象                HttpServletRequest request=ServletActionContext.getRequest();                request.setAttribute("username", "username_request");                                //获取response对象                HttpServletResponse response=ServletActionContext.getResponse();                                //获取session对象                Map
     
       session=ServletActionContext.getContext().getSession();                session.put("username", "username_session");                                //获取ServletContext对象                ServletContext sc=ServletActionContext.getServletContext();                sc.setAttribute("username", "username_application");                                return "text";            }                    }