IDEA reports an error. Error XXX reports an error. The class cannot be found

Scene description

When a relies on B to run a project, the class file in B project cannot be found

The project dependency is intact. There is no problem that the class cannot be found, but an error is reported during operation

Solution:
check whether the JDK configured in idea is consistent with the environment, and whether project B is a runnable project. If it is a runnable project, add the following contents to the POMfile (this problem is caused by bloggers)

<plugin>
  <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-maven-plugin</artifactId>
   <configuration>
       <mainClass>com.xxx</mainClass>
       <skip>true</skip>
   </configuration>
</plugin>

someone runs successfully after checking the following

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