找到解决方案:参考
https://blog.youkuaiyun.com/u014523777/article/details/80993526
本人测试后,方案二有效:
进入workspace/.metadata/.plugins/目录
重命名 org.eclipse.core.resources to org.eclipse.core.resources_old.
然后重启 eclipse
Close eclipse
Delete org.eclipse.core.resources
Rename org.eclipse.core.resources_old back to org.eclipse.core.resources