Tue, 28 Jan 2014 14:56:01 -0800
Added tag jdk8u5-b06 for changeset 956c0e048ef2
1 /*
2 * Copyright (c) 2013, 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 */
24 /*
25 * @test G1AddMetaspaceDependency
26 * @bug 8010196
27 * @summary Checks that we don't get locking problems when adding metaspace dependencies with the G1 update buffer monitor
28 * @run main/othervm -XX:+UseG1GC -XX:G1UpdateBufferSize=1 G1AddMetaspaceDependency
29 */
31 import java.io.InputStream;
33 public class G1AddMetaspaceDependency {
35 static byte[] getClassBytes(String name) {
36 byte[] b = null;
37 try (InputStream is = ClassLoader.getSystemResourceAsStream(name)) {
38 byte[] tmp = new byte[is.available()];
39 is.read(tmp);
40 b = tmp;
41 } finally {
42 if (b == null) {
43 throw new RuntimeException("Unable to load class file");
44 }
45 return b;
46 }
47 }
49 static final String a_name = G1AddMetaspaceDependency.class.getName() + "$A";
50 static final String b_name = G1AddMetaspaceDependency.class.getName() + "$B";
52 public static void main(String... args) throws Exception {
53 final byte[] a_bytes = getClassBytes(a_name + ".class");
54 final byte[] b_bytes = getClassBytes(b_name + ".class");
56 for (int i = 0; i < 1000; i += 1) {
57 runTest(a_bytes, b_bytes);
58 }
59 }
61 static class Loader extends ClassLoader {
62 private final String myClass;
63 private final byte[] myBytes;
64 private final String friendClass;
65 private final ClassLoader friendLoader;
67 Loader(String myClass, byte[] myBytes,
68 String friendClass, ClassLoader friendLoader) {
69 this.myClass = myClass;
70 this.myBytes = myBytes;
71 this.friendClass = friendClass;
72 this.friendLoader = friendLoader;
73 }
75 Loader(String myClass, byte[] myBytes) {
76 this(myClass, myBytes, null, null);
77 }
79 @Override
80 public Class<?> loadClass(String name) throws ClassNotFoundException {
81 Class<?> c = findLoadedClass(name);
82 if (c != null) {
83 return c;
84 }
86 if (name.equals(friendClass)) {
87 return friendLoader.loadClass(name);
88 }
90 if (name.equals(myClass)) {
91 c = defineClass(name, myBytes, 0, myBytes.length);
92 resolveClass(c);
93 return c;
94 }
96 return findSystemClass(name);
97 }
99 }
101 private static void runTest(final byte[] a_bytes, final byte[] b_bytes) throws Exception {
102 Loader a_loader = new Loader(a_name, a_bytes);
103 Loader b_loader = new Loader(b_name, b_bytes, a_name, a_loader);
104 Loader c_loader = new Loader(b_name, b_bytes, a_name, a_loader);
105 Loader d_loader = new Loader(b_name, b_bytes, a_name, a_loader);
106 Loader e_loader = new Loader(b_name, b_bytes, a_name, a_loader);
107 Loader f_loader = new Loader(b_name, b_bytes, a_name, a_loader);
108 Loader g_loader = new Loader(b_name, b_bytes, a_name, a_loader);
110 Class<?> c;
111 c = b_loader.loadClass(b_name);
112 c = c_loader.loadClass(b_name);
113 c = d_loader.loadClass(b_name);
114 c = e_loader.loadClass(b_name);
115 c = f_loader.loadClass(b_name);
116 c = g_loader.loadClass(b_name);
117 }
118 public class A {
119 }
120 class B extends A {
121 }
122 }