【Struts2学习笔记（8）】访问或添加request/session/application属性获取HttpServletRequest / HttpSession / ServletContex
（1）访问或添加request/session/application属性
public String scope() throws Exception{
ActionContext ctx = ActionContext.getContext();
ctx.getApplication().put("app", "应用范围");//往ServletContext里放入app
ctx.getSession().put("ses", "session范围");//往session里放入ses
ctx.put("req", "request范围");//往request里放入req
return "scope";
}
JSP:
<body>
${applicationScope.app} <br>
${sessionScope.ses}<br>
${requestScope.req}<br>
</body>
（2）获取HttpServletRequest / HttpSession / ServletContext / HttpServletResponse对象
方法一，通过ServletActionContext.类直接获取：
public String rsa() throws Exception{
HttpServletRequest request = ServletActionContext.getRequest();
ServletContext servletContext = ServletActionContext.getServletContext();
request.getSession()
HttpServletResponse response = ServletActionContext.getResponse();
return "scope";
}方法二，实现指定接口，由struts框架运行时注入：
public class HelloWorldAction implements ServletRequestAware, ServletResponseAware, ServletContextAware{
private HttpServletRequest request;
private ServletContext servletContext;
private HttpServletResponse response;
public void setServletRequest(HttpServletRequest req) {
this.request=req;
}
public void setServletResponse(HttpServletResponse res) {
this.response=res;
}
public void setServletContext(ServletContext ser) {
this.servletContext=ser;
}
}