After modifying the code, idea does not compile.

Describe the situation I encountered:

1. Every time you modify the code, you need mvn clean install to load the latest code.

2. The test test cannot find the class class

Solution:  

The reason is because someone submitted the .idea code to git. 

After I delete the .idea, I close the idea and reopen the project to change it. 

(The specific reason has not been investigated yet, but it can indeed be solved)