1 /*
2 * Copyright (c) 2011, 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 randomness
27 *
28 * @summary converted from VM Testbase gc/gctests/StringInternSync.
29 * VM Testbase keywords: [gc, stress, stressopt, feature_perm_removal_jdk7, nonconcurrent]
30 * VM Testbase readme:
31 * The test verifies that String.intern is correctly synchronized.
32 * Test interns same strings in different threads and verifies that all interned equal
33 * strings are same objects.
34 * This test interns a few large strings.
35 *
36 * @library /vmTestbase
37 * /test/lib
38 * @run driver jdk.test.lib.FileInstaller . .
39 * @run main/othervm
40 * -XX:+UnlockDiagnosticVMOptions
41 * -XX:+VerifyStringTableAtExit
42 * gc.gctests.StringInternSync.StringInternSync
43 * -ms low
44 */
45
46 package gc.gctests.StringInternSync;
47
48 import java.util.*;
49 import java.util.ArrayList;
50 import java.util.concurrent.locks.ReadWriteLock;
51 import java.util.concurrent.locks.ReentrantReadWriteLock;
52 import nsk.share.TestBug;
53 import nsk.share.TestFailure;
54 import nsk.share.gc.*;
55 import nsk.share.gc.gp.MemoryStrategy;
56 import nsk.share.gc.gp.MemoryStrategyAware;
57 import nsk.share.gc.gp.string.RandomStringProducer;
58
59 public class StringInternSync extends ThreadedGCTest implements MemoryStrategyAware {
60
61 // The list of strings which will be interned
62 static final List<String> stringsToIntern = new ArrayList();
63 // The global container for references to internded strings
64 static final List<List<String>> internedStrings = new ArrayList<List<String>>();
65 // Approximate size occupied by all interned strings
66 long sizeOfAllInteredStrings = 0;
67 // maximum size of one string
68 int maxStringSize;
69 RandomStringProducer gp = new RandomStringProducer();
70 MemoryStrategy memoryStrategy;
71 ReadWriteLock rwlock = new ReentrantReadWriteLock();
72
73 @Override
74 public void setMemoryStrategy(MemoryStrategy memoryStrategy) {
75 this.memoryStrategy = memoryStrategy;
76 }
77
78 private class StringGenerator implements Runnable {
79
80 List<String> internedLocal;
81
82 public StringGenerator(List<String> internedLocal) {
83 this.internedLocal = internedLocal;
84 }
85
86 public void run() {
87 try {
88 rwlock.readLock().lock();
89 internedLocal.clear();
90 for (String str : stringsToIntern) {
91 // Intern copy of string
92 // and save reference to it
93 internedLocal.add(new String(str).intern());
94 }
95 } finally {
96 rwlock.readLock().unlock();
97 }
98
99 // after each iteration 0 thread
100 // lock our main resource and verify String.intern
101 if (internedLocal == internedStrings.get(0)) {
102 try {
103 rwlock.writeLock().lock();
104 // We select first list and compare all other with it
105 // if 2 strings are equal they should be the same "=="
106 List<String> interned = internedStrings.get(0);
107
108 for (List<String> list : internedStrings) {
109 if (list == interned) {
110 continue;
111 }
112 if (list.size() == 0) {
113 continue; // this thread haven't got lock
114 }
115
116 if (list.size() != interned.size()) {
117 throw new TestFailure("Size of interned string list differ from origial."
118 + " interned " + list.size() + " original " + interned.size());
119 }
120 for (int i = 0; i < interned.size(); i++) {
121 String str = interned.get(i);
122 if (!str.equals(list.get(i))) {
123 throw new TestFailure("The interned strings are not the equals.");
124 }
125 if (str != list.get(i)) {
126 throw new TestFailure("The equal interned strings are not the same.");
127 }
128 }
129 list.clear();
130
131 }
132 interned.clear();
133 stringsToIntern.clear();
134 for (long currentSize = 0; currentSize <= sizeOfAllInteredStrings; currentSize++) {
135 stringsToIntern.add(gp.create(maxStringSize));
136 currentSize += maxStringSize;
137 }
138 } finally {
139 rwlock.writeLock().unlock();
140 }
141 }
142 }
143 }
144
145 @Override
146 public void run() {
147 sizeOfAllInteredStrings = 10 * 1024 * 1024; // let use 100 * strings of size 10000
148 maxStringSize = (int) (sizeOfAllInteredStrings / memoryStrategy.getSize(sizeOfAllInteredStrings));
149 log.debug("The overall size of interned strings : " + sizeOfAllInteredStrings / (1024 * 1024) + "M");
150 log.debug("The count of interned strings : " + sizeOfAllInteredStrings / maxStringSize);
151 for (long currentSize = 0; currentSize <= sizeOfAllInteredStrings; currentSize++) {
152 stringsToIntern.add(gp.create(maxStringSize));
153 currentSize += maxStringSize;
154 }
155 super.run();
156 }
157
158 @Override
159 protected Runnable createRunnable(int i) {
160 ArrayList list = new ArrayList();
161 internedStrings.add(list);
162 return new StringGenerator(list);
163 }
164
165 public static void main(String[] args) {
166 GC.runTest(new StringInternSync(), args);
167 }
168 }