ExpiringSessionHttpSession getAttribute Exception - 国内版 Bing
https://cn.bing.com/search?q=ExpiringSessionHttpSession+getAttribute+Exception&qs=n&form=QBRE&sp=-1&pq=expiringsessionhttpsession+getattribute+exception&sc=0-49&sk=&cvid=D742C51BF2B4422A914D66EA1775A7ED
ExpiringSessionHttpSession getAttribute checkState - 国际版 Bing
https://cn.bing.com/search?q=ExpiringSessionHttpSession%20getAttribute%20checkState&qs=n&form=QBRE&sp=-1&pq=expiringsessionhttpsession%20getattribute%20checkstate&sc=0-50&sk=&cvid=4DD1E26C53754F33A9E1EA070104B9A0
NullPointerException in sessionDestroyed listener · Issue #499 · spring-projects/spring-session · GitHub
https://github.com/spring-projects/spring-session/issues/499
Improve session event handling by vpavic · Pull Request #939 · spring-projects/spring-session · GitHub
https://github.com/spring-projects/spring-session/pull/939
Unable to publish SessionDestroyedEvent · Issue #1198 · spring-projects/spring-session · GitHub
https://github.com/spring-projects/spring-session/issues/1198
sessionDestroyed侦听器中的NullPointerException·问题＃499·spring-projects / spring-session·GitHub
https://github.com/spring-projects/spring-session/issues/499
从Spring-Session源码看Session机制的实现细节 - 沧海一滴 - 博客园
https://www.cnblogs.com/softidea/p/10323310.html
spring-session源码解读-4_weixin_34187862的博客-CSDN博客
https://blog.csdn.net/weixin_34187862/article/details/90625332