Reallocate.java revision 8359:ed6389f70257 
1/*
2 * Copyright (c) 2015, 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 * @bug 8058897
27 * @library /testlibrary
28 * @modules java.base/sun.misc
29 *          java.management
30 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:MallocMaxTestWords=100m Reallocate
31 */
32
33import jdk.test.lib.*;
34import sun.misc.Unsafe;
35import static jdk.test.lib.Asserts.*;
36
37public class Reallocate {
38    public static void main(String args[]) throws Exception {
39        Unsafe unsafe = Utils.getUnsafe();
40
41        long address = unsafe.allocateMemory(1);
42        assertNotEquals(address, 0L);
43
44        // Make sure we reallocate correctly
45        unsafe.putByte(address, Byte.MAX_VALUE);
46        address = unsafe.reallocateMemory(address, 2);
47        assertNotEquals(address, 0L);
48        assertEquals(unsafe.getByte(address), Byte.MAX_VALUE);
49
50        // Reallocating with a 0 size should return a null pointer
51        address = unsafe.reallocateMemory(address, 0);
52        assertEquals(address, 0L);
53
54        // Reallocating with a null pointer should result in a normal allocation
55        address = unsafe.reallocateMemory(0L, 1);
56        assertNotEquals(address, 0L);
57        unsafe.putByte(address, Byte.MAX_VALUE);
58        assertEquals(unsafe.getByte(address), Byte.MAX_VALUE);
59
60        // Make sure we can throw an OOME when we fail to reallocate due to OOM
61        try {
62            unsafe.reallocateMemory(address, 100 * 1024 * 1024 * 8);
63        } catch (OutOfMemoryError e) {
64            // Expected
65            return;
66        }
67        throw new RuntimeException("Did not get expected OOM");
68    }
69}
70