Auto-configure VirtualThreadMetrics from micrometer-java21

[shakuzen]

Micrometer added a new MeterBinder for virtual thread metrics via micrometer-metrics/micrometer#5067 - documentation is at https://docs.micrometer.io/micrometer/reference/reference/jvm.html#_java_21_metrics. It is in a new module micrometer-java21. It would be nice if Spring Boot has auto-configuration for VirtualThreadMetrics.

[nosan]

class file has wrong version 65.0, should be 61.0
Please remove or make sure it appears in the correct subdirectory of the classpath.

micrometer-java21 is built using JDK21, whereas Spring Boot source code is JDK17 source compatible, hence either reflection or multi-release jar should be used to add support for VirtualThreadMetrics.

I've prototyped changes in my branch by using reflection and FactoryBean.

I also checked VirtualThreadMetrics with a native-image, and unfortunately, I got the following exception:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'virtualThreadMetrics': Instantiation of supplied bean failed
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.obtainFromSupplier(AbstractAutowireCapableBeanFactory.java:1239)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1176)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:563)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:523)
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:336)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:288)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:334)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.instantiateSingleton(DefaultListableBeanFactory.java:1122)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingleton(DefaultListableBeanFactory.java:1093)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:1030)
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:987)
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:627)
        at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:146)
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752)
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:439)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:318)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1361)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1350)
        at task.gh43122.Gh43122Application.main(Gh43122Application.java:12)
        at java.base@21.0.5/java.lang.invoke.LambdaForm$DMH/sa346b79c.invokeStaticInit(LambdaForm$DMH)
Caused by: java.lang.UnsatisfiedLinkError: jdk.jfr.internal.JVM.getPid()Ljava/lang/String; [symbol: Java_jdk_jfr_internal_JVM_getPid or Java_jdk_jfr_internal_JVM_getPid__]
        at org.graalvm.nativeimage.builder/com.oracle.svm.core.jni.access.JNINativeLinkage.getOrFindEntryPoint(JNINativeLinkage.java:152)
        at org.graalvm.nativeimage.builder/com.oracle.svm.core.jni.JNIGeneratedMethodSupport.nativeCallAddress(JNIGeneratedMethodSupport.java:54)
        at jdk.jfr@21.0.5/jdk.jfr.internal.JVM.getPid(Native Method)
        at jdk.jfr@21.0.5/jdk.jfr.internal.Repository.createRepository(Repository.java:110)
        at jdk.jfr@21.0.5/jdk.jfr.internal.Repository.setBasePath(Repository.java:65)
        at jdk.jfr@21.0.5/jdk.jfr.internal.Repository.ensureRepository(Repository.java:79)
        at jdk.jfr@21.0.5/jdk.jfr.internal.PlatformRecorder.<init>(PlatformRecorder.java:81)
        at jdk.jfr@21.0.5/jdk.jfr.FlightRecorder.getFlightRecorder(FlightRecorder.java:171)
        at jdk.jfr@21.0.5/jdk.jfr.Recording.<init>(Recording.java:107)
        at jdk.jfr@21.0.5/jdk.jfr.Recording.<init>(Recording.java:131)
        at jdk.jfr@21.0.5/jdk.jfr.consumer.RecordingStream.<init>(RecordingStream.java:108)
        at jdk.jfr@21.0.5/jdk.jfr.consumer.RecordingStream.<init>(RecordingStream.java:101)
        at io.micrometer.java21.instrument.binder.jdk.VirtualThreadMetrics.createRecordingStream(VirtualThreadMetrics.java:78)
        at io.micrometer.java21.instrument.binder.jdk.VirtualThreadMetrics.<init>(VirtualThreadMetrics.java:57)
        at io.micrometer.java21.instrument.binder.jdk.VirtualThreadMetrics.<init>(VirtualThreadMetrics.java:49)
        at task.gh43122.Gh43122Application.virtualThreadMetrics(Gh43122Application.java:17)
        at task.gh43122.Gh43122Application$$SpringCGLIB$$0.CGLIB$virtualThreadMetrics$0(<generated>)
        at task.gh43122.Gh43122Application$$SpringCGLIB$$FastClass$$1.invoke(<generated>)
        at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:258)
        at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:348)
        at task.gh43122.Gh43122Application$$SpringCGLIB$$0.virtualThreadMetrics(<generated>)
        at task.gh43122.Gh43122Application__BeanDefinitions.lambda$getVirtualThreadMetricsInstanceSupplier$0(Gh43122Application__BeanDefinitions.java:32)
        at org.springframework.util.function.ThrowingFunction.apply(ThrowingFunction.java:63)
        at org.springframework.util.function.ThrowingFunction.apply(ThrowingFunction.java:51)
        at org.springframework.beans.factory.aot.BeanInstanceSupplier.lambda$get$1(BeanInstanceSupplier.java:219)
        at org.springframework.util.function.ThrowingSupplier.get(ThrowingSupplier.java:58)
        at org.springframework.util.function.ThrowingSupplier.get(ThrowingSupplier.java:46)
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiateWithFactoryMethod(SimpleInstantiationStrategy.java:88)
        at org.springframework.beans.factory.aot.BeanInstanceSupplier.invokeBeanSupplier(BeanInstanceSupplier.java:256)
        at org.springframework.beans.factory.aot.BeanInstanceSupplier.get(BeanInstanceSupplier.java:219)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.obtainInstanceFromSupplier(DefaultListableBeanFactory.java:979)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.obtainFromSupplier(AbstractAutowireCapableBeanFactory.java:1233)
        ... 20 more

Sample to reproduce: gh-43122.zip

mvn clean spring-boot:build-image -Pnative

docker run -p 8080:8080 docker.io/library/gh-43122:0.0.1-SNAPSHOT

[oleksiizaitsev7]

Hi it can be done with some conditions as we have here. But I'm not sure if that is the right way or preferable strategy for the java 21 support