Test with JDK 23 (#428)

.github/workflows/build.yml

@@ -82,6 +82,8 @@ jobs:
             vm: 'openj9'
           - version: 21
             vm: 'openj9'
+          - version: 23
+            vm: 'hotspot'
     steps:
       # We use the cached working directory so that we don't have to recompile everything
       - name: Download cached build working directory

jvmti-access/src/test/java/co/elastic/otel/UniversalProfilingCorrelationTest.java

@@ -42,6 +42,8 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
@@ -185,15 +187,6 @@ public void enablingVirtualThreadSupportDoesNotThrow() {
     @Test
     @EnabledForJreRange(min = JRE.JAVA_21)
     public void testVirtualThreadsExcludedByDefault() throws Exception {
-      if (System.getProperty("java.vm.name").toUpperCase().contains("J9")) {
-        // We exclude this test on OpenJ9, because it is flaky there
-        // It seems like sometimes OpenJ9 does not disable the mount/unmount listeners
-        // even though it didn't report an error
-        // While this can cause this test to fail, in practice this doesn't cause any problems
-        // because we never disable the support after enabling it in the real world
-        return;
-      }
-
       ExecutorService exec =
           (ExecutorService)
               Executors.class.getMethod("newVirtualThreadPerTaskExecutor").invoke(null);
@@ -207,6 +200,9 @@ public void testVirtualThreadsExcludedByDefault() throws Exception {
                     .isNull();
               })
           .get();
+
+      exec.shutdown();
+      exec.awaitTermination(10, TimeUnit.SECONDS);
     }
 
     @Test
@@ -267,6 +263,26 @@ public void testVirtualThreadsStoragePropagatedWithMounts() throws Exception {
       for (Future<?> future : threadResults) {
         future.get(); // this will throw an ExecutionException if any assertions failed
       }
+
+      // We need to properly wait for all virtual threads to be actually ended and unmounted
+      // otherwise we might not correctly remove the virtual-thread TLS attached to the carrier
+      // thread and leak it to other tests
+      exec.shutdown();
+      exec.awaitTermination(10, TimeUnit.SECONDS);
+
+      // Wait until all virtual threads are GCed, just to be sure
+      List<WeakReference<Thread>> threadsWeak =
+          virtualThreads.stream().map(WeakReference::new).collect(Collectors.toList());
+      virtualThreads.clear();
+      threadLatches.clear();
+      threadResults.clear();
+      await()
+          .atMost(Duration.ofSeconds(10))
+          .until(
+              () -> {
+                System.gc();
+                return threadsWeak.stream().allMatch(weakRef -> weakRef.get() == null);
+              });
     }
   }