导入java项目有红×

1.configure build path
https://blog.csdn.net/qq_35016445/article/details/65431503?utm_medium=distribute.pc_relevant.none-task-blogdefaultbaidujs_title~default-no_search_link&spm=1001.2101.3001.4242
2.tomcat jar包导入
https://blog.csdn.net/u012151556/article/details/38173425
3.项目上还有红叉，但内容没有
https://blog.csdn.net/SeanfanJo/article/details/111159558

至此解决完成

附了三个链接，发布转载没法贴三个链接，如侵联系，删