idea struts2.5
参考
https://blog.csdn.net/shuai_wy/article/details/79027573
修复
https://blog.csdn.net/hgx_suiyuesusu/article/details/78167616
详解：Struts2工作原理和执行流程图
https://blog.csdn.net/qq_37230121/article/details/80229927
https://blog.csdn.net/weixin_34310369/article/details/89907838
action:
https://blog.csdn.net/bestmy/article/details/81068026
