1 /*
2 * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @bug 8368799
27 * @summary Verify heapwalking API does not report array classes several times.
28 * @requires vm.jvmti
29 * @modules java.base/jdk.internal.vm.annotation java.base/jdk.internal.value
30 * @enablePreview
31 * @run main/othervm/native -agentlib:HeapwalkDupClasses HeapwalkDupClasses
32 */
33
34 import java.lang.ref.Reference;
35 import jdk.internal.value.ValueClass;
36 import jdk.internal.vm.annotation.NullRestricted;
37 import jdk.internal.vm.annotation.Strict;
38
39 public class HeapwalkDupClasses {
40
41 static native int tagWithFollowReferences(long tag);
42 static native int tagWithIterateOverReachableObjects(long tag);
43 static native Object[] getObjectsWithTags(long tag);
44
45 public static void main(String[] args) throws Exception {
46 System.loadLibrary("HeapwalkDupClasses");
47
48 Integer instance = new Integer(0);
49 Object[] testObjects = new Object[] {
50 new Integer[5],
51 ValueClass.newNullableAtomicArray(Integer.class, 5),
52 ValueClass.newNullRestrictedNonAtomicArray(Integer.class, 5, instance)
53 };
54
55 for (long tag = 1; tag <= 2; tag++) {
56 int taggedClasses;
57 if (tag == 1) {
58 System.out.println("FollowReferences");
59 taggedClasses = tagWithFollowReferences(tag);
60 } else {
61 System.out.println("IterateOverReachableObjects");
62 taggedClasses = tagWithIterateOverReachableObjects(tag);
63 }
64 System.out.println("Tagged " + taggedClasses + " classes");
65
66 Object[] taggedObjects = getObjectsWithTags(tag);
67 System.out.println("Tagged objects (total " + taggedObjects.length + "):");
68
69 int duplicates = 0;
70 boolean foundTestObjectClass[] = new boolean[testObjects.length];
71
72 for (int i = 0; i < taggedObjects.length; i++) {
73 System.out.println("[" + i + "] " + taggedObjects[i]);
74 for (int j = 0; j < i; j++) {
75 if (taggedObjects[i].equals(taggedObjects[j])) {
76 duplicates++;
77 System.out.println(" ERROR: duplicate (" + j + ")");
78 }
79 }
80 for (int j = 0; j < testObjects.length; j++) {
81 if (taggedObjects[i].equals(testObjects[j].getClass())) {
82 foundTestObjectClass[j] = true;
83 System.out.println(" FOUND expected array class");
84 }
85 }
86 }
87 if (duplicates != 0) {
88 throw new RuntimeException("Found " + duplicates + " duplicate classes");
89 }
90 for (int i = 0; i < foundTestObjectClass.length; i++) {
91 if (!foundTestObjectClass[i]) {
92 throw new RuntimeException("Expected class not found: " + testObjects[i].getClass());
93 }
94 }
95 }
96 }
97 }