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 import sun.hotspot.parser.DiagnosticCommand; 28 29 public class WhiteBox { 30 31 @SuppressWarnings("serial") 32 public static class WhiteBoxPermission extends BasicPermission { 33 public WhiteBoxPermission(String s) { 34 super(s); 35 } 36 } 37 38 private WhiteBox() {} 39 private static final WhiteBox instance = new WhiteBox(); 40 private static native void registerNatives(); 41 42 /** 43 * Returns the singleton WhiteBox instance. 44 * 45 * The returned WhiteBox object should be carefully guarded 46 * by the caller, since it can be used to read and write data 47 * at arbitrary memory addresses. It must never be passed to 48 * untrusted code. 49 */ 50 public synchronized static WhiteBox getWhiteBox() { 51 SecurityManager sm = System.getSecurityManager(); 52 if (sm != null) { 53 sm.checkPermission(new WhiteBoxPermission("getInstance")); 54 } 55 return instance; 56 } 57 58 static { 59 registerNatives(); 60 } 61 62 // Memory 63 public native long getObjectAddress(Object o); 64 public native int getHeapOopSize(); 65 66 // Runtime 67 // Make sure class name is in the correct format 68 public boolean isClassAlive(String name) { 69 return isClassAlive0(name.replace('.', '/')); 70 } 71 private native boolean isClassAlive0(String name); 72 73 // G1 74 public native boolean g1InConcurrentMark(); 75 public native boolean g1IsHumongous(Object o); 76 public native long g1NumFreeRegions(); 77 public native int g1RegionSize(); 78 public native Object[] parseCommandLine(String commandline, DiagnosticCommand[] args); 79 }