test/jdk/java/lang/management/ThreadMXBean/ThreadLists.java

@@ -55,10 +55,13 @@
          // Bug id : JDK-8151797
          // Use a lambda expression so that call-site cleaner thread is started
          Runnable printLambda = () -> {System.out.println("Starting Test");};
          printLambda.run();
  
+         // start a virutal thread to cause supporting threads to start
+         Thread.startVirtualThread(() -> { });
+ 
          // get top-level thread group
          ThreadGroup top = Thread.currentThread().getThreadGroup();
          ThreadGroup parent;
          do {
              parent = top.getParent();