How to get KQueue to be available in Java in OSX?-CodePudding

My packages are as following:

    implementation("io.netty:netty-transport-native-epoll:$nettyVersion")
    implementation("io.netty:netty-transport-native-kqueue:$nettyVersion")
    implementation("io.netty:netty-transport-native-epoll:$nettyVersion:linux-aarch_64")
    implementation("io.netty:netty-transport-native-epoll:$nettyVersion:linux-x86_64")
    implementation("io.netty:netty-transport-native-kqueue:$nettyVersion:osx-x86_64")

Gradle showing the package getting installed correctly: (where <source> is the path to our internal library storage)

Cached resource <source>/releases/io/netty/netty-transport-native-kqueue/4.1.78.Final/netty-transport-native-kqueue-4.1.78.Final-osx-x86_64.jar is up-to-date (lastModified: Fri Jun 24 17:45:28 PDT 2022).

Gradle output showing the system:

------------------------------------------------------------------------
Detecting the operating system and CPU architecture
------------------------------------------------------------------------
os.detected.name=osx
os.detected.arch=x86_64
os.detected.version=12.4
os.detected.version.major=12
os.detected.version.minor=4
os.detected.classifier=osx-x86_64

Simplest way I can reproduce is:

KQueue.isAvailable()

returns false.

If I run the following to get more information:

KQueue.unavailabilityCause().printStackTrace();

I get: (removed repeating or unnecessary stack traces)

java.lang.UnsatisfiedLinkError: could not load a native library: netty_transport_native_kqueue_x86_64
        at io.netty.util.internal.NativeLibraryLoader.load(NativeLibraryLoader.java:239)
        at io.netty.channel.kqueue.Native.loadNativeLibrary(Native.java:155)
        ...
        Suppressed: java.lang.UnsatisfiedLinkError: no netty_transport_native_kqueue_x86_64 in java.library.path: /Users/kdilsiz/Library/Java/Extensions:/Library/Java/Extensions:/Network/Library/Java/Extensions:/System/Library/Java/Extensions:/usr/lib/java:.
        ...

Am I not supposed to be able to run this code? What am I missing?

If I search online for the error, it shows outdated Netty package loading errors (only showing up in debug level logging). This is NOT my problem. The package loads correctly when I run gradle and I can see it is being cached/loaded with gradle -info --refresh-dependencies.

CodePudding user response：

It was due to one of the dependencies importing netty-all. This was causing the Kqueue packages to be imported twice and with different versions.

The problem was that I did not fully read the stack trace from:

KQueue.unavailabilityCause().printStackTrace();

In the end of that stack trace, it said:

Caused by: java.lang.IllegalStateException: Multiple resources found for 'META-INF/native/libnetty_transport_native_kqueue_x86_64.jnilib' with different content:
...

After that, I was able to find where the package was coming from and fix it. Then I was able to locally run the Java Code to run domain socket and test it locally.

I used IntelliJ to run it after the fix. (VsCode had a problem even after the fix, hence wanted to mention it)