1 /*
2 * Copyright (c) 2007, 2018, 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 * @key stress gc
27 *
28 * @summary converted from VM Testbase gc/gctests/WeakReference/weak006.
29 * VM Testbase keywords: [gc, stress, stressopt, nonconcurrent]
30 *
31 * @library /vmTestbase
32 * /test/lib
33 * @run driver jdk.test.lib.FileInstaller . .
34 * @run main/othervm -XX:-UseGCOverheadLimit gc.gctests.WeakReference.weak006.weak006 -t 1
35 */
36
37 package gc.gctests.WeakReference.weak006;
38
39 import nsk.share.test.*;
40 import nsk.share.gc.*;
41 import nsk.share.TestFailure;
42 import java.lang.ref.WeakReference;
43 import java.lang.ref.SoftReference;
44 import java.lang.ref.PhantomReference;
45 import java.lang.ref.Reference;
46
47 /**
48 * Test that GC correctly clears references.
49 *
50 * This test randomly creates a number of weak, soft,
51 * phantom and strong references, each of which points
52 * to the next, then provokes GC with Algorithms.eatMemory().
53 * The test succedes if last reference has been cleared.
54 */
55 public class weak006 extends ThreadedGCTest {
56
57 class Worker implements Runnable {
58
59 private int length;
60 private int objectSize = 100;
61 private Object[] references;
62 private Reference lastReference;
63
64 private Object makeReference(int n, Object o) {
65 switch (n) {
66 case 0:
67 return new WeakReference(o);
68 case 1:
69 return new SoftReference(o);
70 case 2:
71 return new PhantomReference(o, null);
72 case 4: {
73 // Array of strong references
74 int len = Memory.getArrayLength(objectSize, Memory.getReferenceSize());
75 Object[] arr = new Object[len];
76 for (int i = 0; i < len; ++i) {
77 arr[i] = o;
78 }
79 return arr;
80 }
81 case 5: {
82 // reference to array of strong references and strong reference to reference
83 int len = Memory.getArrayLength(objectSize, Memory.getReferenceSize());
84 Object[] arr = new Object[len];
85 for (int i = 1; i < len; ++i) {
86 arr[i] = o;
87 }
88 Reference ref = (Reference) makeReference(LocalRandom.nextInt(3), arr);
89 if (len > 0) {
90 arr[0] = ref;
91 }
92 return ref;
93 }
94 case 3:
95 default:
96 // Strong reference
97 return o;
98 }
99 }
100
101 private void clear() {
102 lastReference = null;
103 references[length - 1] = null;
104 }
105
106 private void makeReferences(int n) {
107 clear();
108 MemoryObject obj = new MemoryObject(objectSize);
109 references[0] = new WeakReference(obj);
110 for (int i = 1; i < length; ++i) {
111 if (i != length - 1) {
112 references[i] = makeReference(LocalRandom.nextInt(2), references[i - 1]);
113 } else {
114 lastReference = (Reference) makeReference(n, references[i - 1]);
115 references[i] = lastReference;
116 }
117 }
118 for (int i = 0; i < length; ++i) {
119 references[i] = null;
120 }
121 }
122
123 public void run() {
124 makeReferences(0);
125 ExecutionController stresser = getExecutionController();
126 Algorithms.eatMemory(stresser);
127 if (!stresser.continueExecution()) {
128 return;
129 }
130 if (lastReference.get() != null) {
131 references = null;
132 throw new TestFailure("Last weak reference has not been cleared");
133 }
134 makeReferences(1);
135 Algorithms.eatMemory(stresser);
136 if (!stresser.continueExecution()) {
137 return;
138 }
139 if (lastReference.get() != null) {
140 references = null;
141 throw new TestFailure("Last soft reference has not been cleared");
142 }
143 }
144
145 public Worker() {
146 length = Memory.getArrayLength(runParams.getTestMemory() - objectSize, Memory.getReferenceSize() + objectSize);
147 System.out.println("Array size: " + length);
148 references = new Object[length];
149 }
150 }
151
152 @Override
153 protected Runnable createRunnable(int i) {
154 return new Worker();
155 }
156
157 public static void main(String[] args) {
158 GC.runTest(new weak006(), args);
159 }
160 }