7. Solve the problem that Idea implements the interface without @Override

Solution:

The language level is determined to be above 1.6, OK.

If the following exception occurs after solving the Override problem:

Error:java: Compilation failed: internal java compiler error

Then set the following page settings in settings:

I personally tried it, and the Target bytecode version is determined to be above 1.6, and there is no problem.

 

However, there is still a problem after the project is refreshed, and it is found that the version has changed back to 1.5. How did this happen:

in the project's pom.xml

<build>
   <plugins>
      <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-compiler-plugin</artifactId>
         <version>2.3.2</version>
         <configuration>
            <source>1.8</source>
            <target>1.8</target>
         </configuration>
      </plugin>
   </plugins>
</build>