@SessionAttribute

如果需要访问全局管理的预先存在的会话属性（即，不在控制器外部 - 例如，由过滤器管理），并且这些属性可能存在或不存在，那么可以在方法参数上使用 @SessionAttribute 注解，如下例所示：

If you need access to pre-existing session attributes that are managed globally (that is, outside the controller — for example, by a filter) and may or may not be present, you can use the @SessionAttribute annotation on a method parameter, as the following example shows:

Java
@RequestMapping("/")
public String handle(@SessionAttribute User user) { 1
	// ...
}
1 Using a @SessionAttribute annotation.
Kotlin
@RequestMapping("/")
fun handle(@SessionAttribute user: User): String { (1)
	// ...
}
2 Using a @SessionAttribute annotation.======

对于需要添加或移除会话属性的用例，请考虑将 org.springframework.web.context.request.WebRequest 或 jakarta.servlet.http.HttpSession 注入到控制器方法中。

For use cases that require adding or removing session attributes, consider injecting org.springframework.web.context.request.WebRequest or jakarta.servlet.http.HttpSession into the controller method.

如 @SessionAttributes 所述，对于在会话中作为控制器工作流的一部分的模型属性的临时存储，请考虑使用 @SessionAttributes。

For temporary storage of model attributes in the session as part of a controller workflow, consider using @SessionAttributes as described in @SessionAttributes.