1、若希望在多个请求之间共用某个模型属性数据,则可以在控制器类上标注一个@SessionAttributes注解, SpringMVC将在模型中对应的属性暂存到HttpSession中,该注解只能放在类的上面,而不能修饰方法。
2、@SessionAttributes除了可以通过属性名指定需要放到会话中的属性外,还可以通过模型属性的对象类型指定哪些模型属性需要放到会话中
(1)@SessionAttributes(types=User.class) 会将隐含模型中所有类型为User.class的属性添加到会话中
(2)@SessionAttributes(value={"username", "password"})
(3)@SessionAttributes(types={User.class, Dept.class})
(4)@SessionAttributes(value={"username", "password"},types={Dept.class})
3、控制器类TestRequestMappingController.java
package com.springmvc.web.controller; import java.util.Map; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.SessionAttributes; import com.springmvc.bean.UserBean; @SessionAttributes(value={"username","password"},types=UserBean.class) @Controller @RequestMapping("/springmvc") public class TestRequestMappingController { @RequestMapping("/testSessionAttributes") public String testSessionAttributes(Map<String, Object> map) { map.put("username", "lipiaoshui"); map.put("password", "123456"); UserBean user = new UserBean("zhangsan", "111111", 20); map.put("user", user); return "success"; } }
4、访问代码
<a href="<%=path%>/springmvc/testSessionAttributes">Test SessionAttributes</a>
5、显示层代码
request username: ${requestScope.username }<br> request password: ${requestScope.password }<br> session username: ${sessionScope.username }<br> session password: ${sessionScope.password }<br> request user:${requestScope.user }<br> sessin user:${sessionScope.user }<br>
6、显示效果