Javaweb_Servlet_Session

Session-Server side(store info in server, server created the session)

server(tomcat) will create a session to each client(browser), one session with one browser.

 1  //中文乱码问题，英文环境不需要考虑该情况.
 2         req.setCharacterEncoding("utf-8");
 3         resp.setCharacterEncoding("utf-8");
 4         resp.setContentType("text/html;charset=utf-8");
 5         //get session
 6         HttpSession session = req.getSession();
 7         session.setAttribute("name", "Mingyue");//set value to session
 8         String sessionId = session.getId();//get session id
 9         //to know whether the session is new or not
10         if (session.isNew()) {
11             resp.getWriter().write("created a session, ID = " + sessionId);
12         } else {
13             resp.getWriter().write("session existed in the server and ID = " + sessionId);
14         }
15         //what happened when session created
16 //        Cookie cookie = new Cookie("JSESSIONID", sessionId);
17 //        resp.addCookie(cookie);

get attribute of session.

1 HttpSession session = req.getSession();
2         String name = (String) session.getAttribute("name");//get 
3         resp.getWriter().write(name);
4         System.out.println(name);

remove attribute and invalidate session.

1  HttpSession session = req.getSession();
2         session.removeAttribute("name");
3         session.invalidate();

set attribute as an object and get attibute of it.

1  session.setAttribute("name",new Person("Mingyue",1));//set an object in session
2   Object name = session.getAttribute("name");
3         resp.getWriter().write(name.toString());
4         System.out.println(name.toString());

 configure session time in xml.

1  <session-config>
2 <!--expired in 15 min-->
3     <session-timeout>15</session-timeout>
4   </session-config>

 

posted @ 2023-06-14 06:59  ming1010  阅读(16)  评论(0)    收藏  举报