1 /*
   2  * Copyright (c) 2012, 2012, 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 package jdk.vm.ci.hotspot;
  24 
  25 import java.lang.reflect.Field;
  26 
  27 import sun.misc.Unsafe;
  28 
  29 /**
  30  * Package private access to the {@link Unsafe} capability.
  31  */
  32 class UnsafeAccess {
  33 
  34     static final Unsafe UNSAFE = initUnsafe();
  35 
  36     private static Unsafe initUnsafe() {
  37         try {
  38             // Fast path when we are trusted.
  39             return Unsafe.getUnsafe();
  40         } catch (SecurityException se) {
  41             // Slow path when we are not trusted.
  42             try {
  43                 Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
  44                 theUnsafe.setAccessible(true);
  45                 return (Unsafe) theUnsafe.get(Unsafe.class);
  46             } catch (Exception e) {
  47                 throw new RuntimeException("exception while trying to get Unsafe", e);
  48             }
  49         }
  50     }
  51 }