8265796: vmTestbase/nsk/jdi/ObjectReference/referringObjects/referringObjects002/referringObjects002.java fails when running with JEP 416

Reviewed-by: cjplummer, mchung

Author: lmesnik

test/hotspot/jtreg/ProblemList.txt

@@ -38,7 +38,6 @@
 #
 #############################################################################
 
-vmTestbase/nsk/jdi/ObjectReference/referringObjects/referringObjects002/referringObjects002.java 8265796  generic-all
 
 #############################################################################
 

test/hotspot/jtreg/vmTestbase/nsk/jdi/ObjectReference/referringObjects/referringObjects002/referringObjects002.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -56,14 +56,17 @@
  * @build nsk.jdi.ObjectReference.referringObjects.referringObjects002.referringObjects002
  *        nsk.jdi.ObjectReference.referringObjects.referringObjects002.referringObjects002a
  *        nsk.share.jdi.TestClass1
+ * @build sun.hotspot.WhiteBox
+ * @run driver jdk.test.lib.helpers.ClassFileInstaller sun.hotspot.WhiteBox
  * @run main/othervm/native
  *      nsk.jdi.ObjectReference.referringObjects.referringObjects002.referringObjects002
  *      -verbose
  *      -arch=${os.family}-${os.simpleArch}
  *      -waittime=5
  *      -debugee.vmkind=java
  *      -transport.address=dynamic
- *      -debugee.vmkeys="-Xmx256M ${test.vm.opts} ${test.java.opts}"
+ *      -debugee.vmkeys="-Xmx256M -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
+ *                       -XX:+WhiteBoxAPI  ${test.vm.opts} ${test.java.opts}"
  *      -testClassPath ${test.class.path}
  */
 
@@ -97,6 +100,10 @@ protected String debuggeeClassName() {
 
     public void checkClassObjectReferrersCount(ClassObjectReference classObjectReference, int expectedCount) {
         int referrersCount = classObjectReference.referringObjects(0).size();
+        log.display("References:");
+        for (ObjectReference ref: classObjectReference.referringObjects(0)) {
+            log.display(ref);
+        }
 
         if (referrersCount != expectedCount) {
             setSuccess(false);
@@ -137,7 +144,6 @@ protected void doTest() {
         expectedReferrersCount = 3;
 
         checkClassObjectReferrersCount(classObjectReference, expectedReferrersCount);
-
         // disable collection and try unload class object
         classObjectReference.disableCollection();
 

test/hotspot/jtreg/vmTestbase/nsk/jdi/ObjectReference/referringObjects/referringObjects002/referringObjects002a.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -29,6 +29,7 @@
 import nsk.share.jdi.HeapwalkingDebuggee;
 import java.io.*;
 import java.util.*;
+import sun.hotspot.WhiteBox;
 
 /*
  * Class create and save given number of class instances
@@ -56,6 +57,8 @@ public class referringObjects002a extends HeapwalkingDebuggee {
 
     final static public String COMMAND_DELETE_CLASS_OBJECT_REFERRERS = "deleteClassObjectReferrers";
 
+    private final WhiteBox WB = WhiteBox.getWhiteBox();
+
     public static void main(String args[]) {
         new referringObjects002a().doTest(args);
     }
@@ -76,6 +79,9 @@ public void createClassObjectReferrers(String className, int instanceCount) {
 
         for (String referenceType : ObjectInstancesManager.allReferenceTypes)
             classReferrers.add(new ReferringObject(klass, referenceType));
+        // force full GC with WB to ensure that weak refernces are collected
+        // j.l.i.MethodType has ConcurrentWeakInternSet which might contain references to TestClass1
+        WB.fullGC();
     }
 
     // delete all created references to class object