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 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:MallocMaxTestWords=20m Reallocate 29 */ 30 31 import com.oracle.java.testlibrary.*; 32 import sun.misc.Unsafe; 33 import static com.oracle.java.testlibrary.Asserts.*; 34 35 public class Reallocate { 36 public static void main(String args[]) throws Exception { 37 Unsafe unsafe = Utils.getUnsafe(); 38 39 long address = unsafe.allocateMemory(1); 40 assertNotEquals(address, 0L); 41 42 // Make sure we reallocate correctly 43 unsafe.putByte(address, Byte.MAX_VALUE); 44 address = unsafe.reallocateMemory(address, 2); 45 assertNotEquals(address, 0L); 46 assertEquals(unsafe.getByte(address), Byte.MAX_VALUE); 47 48 // Reallocating with a 0 size should return a null pointer 49 address = unsafe.reallocateMemory(address, 0); 50 assertEquals(address, 0L); 51 52 // Reallocating with a null pointer should result in a normal allocation 53 address = unsafe.reallocateMemory(0L, 1); 54 assertNotEquals(address, 0L); 55 unsafe.putByte(address, Byte.MAX_VALUE); 56 assertEquals(unsafe.getByte(address), Byte.MAX_VALUE); 57 58 // Make sure we can throw an OOME when we fail to reallocate due to OOM 59 try { 60 unsafe.reallocateMemory(address, 20 * 1024 * 1024 * 8); 61 } catch (OutOfMemoryError e) { 62 // Expected 63 return; 64 } 65 throw new RuntimeException("Did not get expected OOM"); 66 } 67 }