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Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Sun Dec 08 12:22:59 CST 2019
There was an unexpected error (type=Internal Server Error, status=500).
An error happened during template parsing (template: "class path resource [templates/adminManageCourse.html]")
Turned out to be related with the controller in order to write. . .
@Controller things down in writing it down. . .
It stands to reason should not be, ah, can I write the order changed inexplicably good. .
Metaphysics in general. . .
I do not know why. .