|
10230
|
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 */
|
|
|
23
|
|
|
24 /*
|
|
|
25 * @test KeepAliveSoftReference
|
|
|
26 * @summary This test case uses a java.lang.ref.SoftReference referencing a class instance to keep a class alive.
|
|
|
27 * @library /testlibrary /testlibrary/whitebox /runtime/testlibrary
|
|
|
28 * @library classes
|
|
|
29 * @build KeepAliveSoftReference test.Empty
|
|
|
30 * @build ClassUnloadCommon
|
|
|
31 * @run main ClassFileInstaller sun.hotspot.WhiteBox
|
|
|
32 * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI KeepAliveSoftReference
|
|
|
33 */
|
|
|
34
|
|
|
35 import java.lang.ref.SoftReference;
|
|
|
36 import sun.hotspot.WhiteBox;
|
|
|
37
|
|
|
38 /**
|
|
|
39 * Test that verifies that classes are not unloaded when specific types of references are kept to them.
|
|
|
40 */
|
|
|
41 public class KeepAliveSoftReference {
|
|
|
42 private static final String className = "test.Empty";
|
|
|
43 private static final WhiteBox wb = WhiteBox.getWhiteBox();
|
|
|
44
|
|
|
45 public static void main(String... args) throws Exception {
|
|
|
46 ClassLoader cl = ClassUnloadCommon.newClassLoader();
|
|
|
47 Class<?> c = cl.loadClass(className);
|
|
|
48 Object o = c.newInstance();
|
|
|
49 SoftReference<Object> sr = new SoftReference(o);
|
|
|
50 o = null; c = null; cl = null;
|
|
|
51
|
|
|
52 {
|
|
|
53 boolean isAlive = wb.isClassAlive(className);
|
|
|
54 System.out.println("testSoftReference (1) alive: " + isAlive);
|
|
|
55 boolean cleared = (sr.get() == null);
|
|
|
56 boolean shouldBeAlive = !cleared;
|
|
|
57 ClassUnloadCommon.failIf(isAlive != shouldBeAlive, "" + isAlive + " != " + shouldBeAlive);
|
|
|
58 }
|
|
|
59
|
|
|
60 ClassUnloadCommon.triggerUnloading();
|
|
|
61
|
|
|
62 {
|
|
|
63 boolean isAlive = wb.isClassAlive(className);
|
|
|
64 System.out.println("testSoftReference (2) alive: " + isAlive);
|
|
|
65 boolean cleared = (sr.get() == null);
|
|
|
66 boolean shouldBeAlive = !cleared;
|
|
|
67 ClassUnloadCommon.failIf(isAlive != shouldBeAlive, "" + isAlive + " != " + shouldBeAlive);
|
|
|
68 }
|
|
|
69 sr.clear();
|
|
|
70 ClassUnloadCommon.triggerUnloading();
|
|
|
71
|
|
|
72 {
|
|
|
73 boolean isAlive = wb.isClassAlive(className);
|
|
|
74 System.out.println("testSoftReference (3) alive: " + isAlive);
|
|
|
75 boolean cleared = (sr.get() == null);
|
|
|
76 boolean shouldBeAlive = !cleared;
|
|
|
77 ClassUnloadCommon.failIf(isAlive != shouldBeAlive, "" + isAlive + " != " + shouldBeAlive);
|
|
|
78 }
|
|
|
79 }
|
|
|
80 }
|
