stop IntelliJ IDEA to switch java language level every time the pom is reloaded (or change the default project language level)

Question

Using IntelliJ 12, I have a java project and I use maven with a pom.xml. My project is using java8, but it seems the default project language level has been set to 6 while importing the project.

I can change the language level to 8.0 (F4 -> Modules -> Language level) however every time I edit my pom.xml the project level is switched back to "use project language level", and I have to edit this settings again and again.

Is there something I need to add to the pom.xml to set the default language level to 8.0?

Answer 1

As per Mark's comment, here is how to do it:

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.5.1</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>
    </plugins>
</build>