IntelliJ IDEA does not index Spring libraries, what should I do?

Question

Java

Good day.
In general, I ran into a problem: IDEA does not offer me to substitute spring-a library classes, everything is fine with all other libraries. And when writing the full class name from these libraries, automatic import does not offer.
If you write manually the import of the required classes, then everything works.
Github project (my first project).
PS any comments on the code are welcome, and preferably with explanations ^_^

Answer 1

Try doing a maven re-import or re-importing the entire project.

Answer 2

Buy the full version