UnsafeAccess.java revision 12968:4d8a004e5c6d 
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 */
23package org.graalvm.compiler.replacements;
24
25import java.lang.reflect.Field;
26
27import sun.misc.Unsafe;
28
29/**
30 * Package private access to the {@link Unsafe} capability.
31 */
32class 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}
52