【学习笔记15】访问或添加几个属性

一、访问或添加request/session/application属性：

Action：
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
   //System.out.println("servletContext.getAttribute : " + (String) (ctx.getApplication().get("app")));
   return "scope";
}

JSP：
${applicationScope.app}<br>
${sessionScope.ses}<br>
${requestScope.req}<br>

二、获取HttpServletRequest / HttpSession / ServletContext / HttpServletResponse对象：
方法1，通过ServletActionContext类直接获取：

public String rsa() throws Exception{
  HttpServletRequest request = ServletActionContext.getRequest();
  ServletContext servletContext = ServletActionContext.getServletContext();
  HttpServletResponse response = ServletActionContext.getResponse();
  HttpSession session = request.getSession();
  return "scope";
}

方法2，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;
  }
}

（本学习笔记是根据传智播客的视频教程整理而来）