AwtListGarbageCollectionTest.java revision 14851:980da45565c8 
1/*
2 * Copyright (c) 2014, 2016, 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 headful
27 * @bug 8040076
28 * @summary AwtList not garbage collected
29 * @run main/othervm -Xmx100m AwtListGarbageCollectionTest
30 */
31
32import java.awt.*;
33import java.awt.event.WindowAdapter;
34import java.awt.event.WindowEvent;
35import java.lang.ref.WeakReference;
36
37public class AwtListGarbageCollectionTest {
38    public static void main(String[] args) {
39        Frame frame = new Frame("List leak test");
40        try {
41            test(frame);
42        } finally {
43            frame.dispose();
44        }
45    }
46
47    private static void test(Frame frame) {
48        WeakReference<List> weakListRef = null;
49        try {
50            frame.setSize(300, 200);
51            frame.setVisible(true);
52
53            List strongListRef = new List();
54            frame.add(strongListRef);
55            strongListRef.setMultipleMode(true);
56            frame.remove(strongListRef);
57            weakListRef = new WeakReference<List>(strongListRef);
58            strongListRef = null;
59
60            //make out of memory to force gc
61            String veryLongString = new String(new char[100]);
62            while (true) {
63                veryLongString += veryLongString;
64            }
65        } catch (OutOfMemoryError e) {
66            if (weakListRef == null) {
67                throw new RuntimeException("Weak list ref wasn't created");
68            } else if (weakListRef.get() != null) {
69                throw new RuntimeException("List wasn't garbage collected");
70            }
71        }
72    }
73}
74