struts2关于request、session和application

?? 1、访问或添加request/session/application属性（此种方式适合仅仅是往3个范围放入属性）

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2、获取HttpServletRequest/HttpSession/ServletContext/HttpServletResponse对象
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??? 方法一：通过ServletActionContext类直接获取（适用获取站点目录下某文件的绝对路径）?
public class HelloWorldAction implements ServletRequestAware,ServletResponseAware,ServletContextAware {private HttpServletRequest request;private ServletContext servletContext;private HttpServletResponse response;@Overridepublic void setServletContext(ServletContext ser) {this.servletContext = ser;}@Overridepublic void setServletResponse(HttpServletResponse rpo) {this.response = rpo;}@Overridepublic void setServletRequest(HttpServletRequest req) {this.request = req;}public String rsa() {request.setAttribute("req", "请求范围属性");request.getSession().setAttribute("ses", "会话范围属性");servletContext.setAttribute("app", "应用范围属性");return "success";}}
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