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  * @summary Verifies behaviour of Unsafe.allocateMemory
  27  * @library /testlibrary
  28  * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:MallocMaxTestWords=20m AllocateMemory
  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 AllocateMemory {
  36     public static void main(String args[]) throws Exception {
  37         Unsafe unsafe = Utils.getUnsafe();
  38 
  39         // Allocate a byte, write to the location and read back the value
  40         long address = unsafe.allocateMemory(1);
  41         assertNotEquals(address, 0L);
  42 
  43         unsafe.putByte(address, Byte.MAX_VALUE);
  44         assertEquals(Byte.MAX_VALUE, unsafe.getByte(address));
  45         unsafe.freeMemory(address);
  46 
  47         // Call to allocateMemory() with a negative value should result in an IllegalArgumentException
  48         try {
  49             address = unsafe.allocateMemory(-1);
  50             throw new RuntimeException("Did not get expected IllegalArgumentException");
  51         } catch (IllegalArgumentException e) {
  52             // Expected
  53             assertNotEquals(address, 0L);
  54         }
  55 
  56         // allocateMemory() should throw an OutOfMemoryError when the underlying malloc fails,
  57         // we test this by limiting the malloc using -XX:MallocMaxTestWords
  58         try {
  59             address = unsafe.allocateMemory(20 * 1024 * 1024 * 8);
  60         } catch (OutOfMemoryError e) {
  61             // Expected
  62             return;
  63         }
  64         throw new RuntimeException("Did not get expected OutOfMemoryError");
  65     }
  66 }