The debug of the SpringBoot project is started, there is no tick in the red dot

I encountered this problem when working on a project today, here is a note! ! !

The Debug mode of the project started successfully, and the breakpoint found that there was no red hook in the red dot, which caused the breakpoint to fail!

solution:

1. Check whether the Controller class is annotated with @Controller
2. Press Ctrl+F9 to recompile
3. When SpringBoot starts, it does not scan the package where the Controller is located, as shown in the figure below ( this method is a solution to my problems )