What's Changed

1. Remove jdk9-compile profile configuration from pom.xml. For now, Unsafe will be considered as nonexistent package if set maven.compiler.release, no matter the release is set to 8 or not. see details at There are difference between maven.compiler.release and maven.compiler.target during compiling projects which use sun.misc.Unsafe with JDK17+ maven-compiler-plugin#990
2. Call position method of java.nio.Buffer instead of java.nio.ByteBuffer for the sake of jdk8 compatibility since position method had been moved from java.nio.Buffer to its subclass java.nio.ByteBuffer since jdk9+.

What is the purpose of the change?

The release configuration of jdk9-compile profile will cause trouble if we compile dubbo with jdk17+ and use sun.misc.Unsafe like this,

import sun.misc.Unsafe;

import static org.apache.dubbo.common.constants.CommonConstants.ThirdPartyProperty.GRAALVM_NATIVEIMAGE_IMAGECODE;

public abstract class NativeDetector {
    private Unsafe UNSAFE;
    ...

Cause

sun.misc.Unsafe had been moved to jdk.unsupported module since jdk9+, it could not be added if set maven.compiler.release

When using --release to specify a release that supports the Java Platform Module System, the --add-exports option cannot be used to enlarge the set of packages exported by the Java SE, JDK, and standard modules in the specified release.

see details at https://docs.oracle.com/en/java/javase/25/docs/specs/man/javac.html#option-release

Checklist

• Make sure there is a GitHub_issue field for the change.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit-test to verify your logic correction. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Make sure gitHub actions can pass. Why the workflow is failing and how to fix it?