Document that spring-boot-starter-parent sets maven.compiler.release and how to unset it if needed

[brucelwl]

springboot 3.2.0-RC1

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <configuration>
        <compilerArgs>
            <arg>--add-exports=java.base/jdk.internal.misc=ALL-UNNAMED</arg>
            <arg>--add-exports=java.base/jdk.internal.vm=ALL-UNNAMED</arg>
        </compilerArgs>
    </configuration>
</plugin>

the default property <maven.compiler.release>${java.version}</maven.compiler.release>

cause error

exporting a package from system module java.base is not allowed with --release

see

source plexus-compiler-javac-2.13.0.jar

[wilkinsona]

Thanks for trying to RC. Have you only just started seeing this problem? We started setting maven.compiler.release in 3.1.

[brucelwl]

I previously discovered this PR #34365, but it still caused my program to not compile properly, and currently I have not found a corresponding solution

[wilkinsona]

Yes, I suspect that #34365 introduced the problem. However, if that is the case, this would also fail with Spring Boot 3.1. Does it?

[brucelwl]

@wilkinsona I tried using Spring Boot version 3.1 and found the same problem