5915
|
1 /*
|
|
2 * Copyright (c) 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 */
|
|
24
|
|
25 package sun.hotspot;
|
|
26 import java.security.BasicPermission;
|
|
27
|
|
28 public class WhiteBox {
|
|
29
|
|
30 @SuppressWarnings("serial")
|
|
31 public static class WhiteBoxPermission extends BasicPermission {
|
|
32 public WhiteBoxPermission(String s) {
|
|
33 super(s);
|
|
34 }
|
|
35 }
|
|
36
|
|
37 private WhiteBox() {}
|
|
38 private static final WhiteBox instance = new WhiteBox();
|
|
39 private static native void registerNatives();
|
|
40
|
|
41 /**
|
|
42 * Returns the singleton WhiteBox instance.
|
|
43 *
|
|
44 * The returned WhiteBox object should be carefully guarded
|
|
45 * by the caller, since it can be used to read and write data
|
|
46 * at arbitrary memory addresses. It must never be passed to
|
|
47 * untrusted code.
|
|
48 */
|
|
49 public synchronized static WhiteBox getWhiteBox() {
|
|
50 SecurityManager sm = System.getSecurityManager();
|
|
51 if (sm != null) {
|
|
52 sm.checkPermission(new WhiteBoxPermission("getInstance"));
|
|
53 }
|
|
54 return instance;
|
|
55 }
|
|
56
|
|
57 static {
|
|
58 registerNatives();
|
|
59 }
|
|
60
|
|
61 // Memory
|
|
62 public native long getObjectAddress(Object o);
|
|
63 public native int getHeapOopSize();
|
|
64
|
|
65 // G1
|
|
66 public native boolean g1InConcurrentMark();
|
|
67 public native boolean g1IsHumongous(Object o);
|
|
68 public native long g1NumFreeRegions();
|
|
69 public native int g1RegionSize();
|
|
70 }
|