1 /*
   2  * Copyright (c) 2012, 2013 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 
  27 import java.lang.reflect.Method;
  28 import java.security.BasicPermission;
  29 import sun.hotspot.parser.DiagnosticCommand;
  30 
  31 public class WhiteBox {
  32 
  33   @SuppressWarnings("serial")
  34   public static class WhiteBoxPermission extends BasicPermission {
  35     public WhiteBoxPermission(String s) {
  36       super(s);
  37     }
  38   }
  39 
  40   private WhiteBox() {}
  41   private static final WhiteBox instance = new WhiteBox();
  42   private static native void registerNatives();
  43 
  44   /**
  45    * Returns the singleton WhiteBox instance.
  46    *
  47    * The returned WhiteBox object should be carefully guarded
  48    * by the caller, since it can be used to read and write data
  49    * at arbitrary memory addresses. It must never be passed to
  50    * untrusted code.
  51    */
  52   public synchronized static WhiteBox getWhiteBox() {
  53     SecurityManager sm = System.getSecurityManager();
  54     if (sm != null) {
  55       sm.checkPermission(new WhiteBoxPermission("getInstance"));
  56     }
  57     return instance;
  58   }
  59 
  60   static {
  61     registerNatives();
  62   }
  63 
  64   // Arguments
  65   public native void printHeapSizes();
  66 
  67   // Memory
  68   public native long getObjectAddress(Object o);
  69   public native int  getHeapOopSize();
  70 
  71   // Runtime
  72   // Make sure class name is in the correct format
  73   public boolean isClassAlive(String name) {
  74     return isClassAlive0(name.replace('.', '/'));
  75   }
  76   private native boolean isClassAlive0(String name);
  77 
  78   // G1
  79   public native boolean g1InConcurrentMark();
  80   public native boolean g1IsHumongous(Object o);
  81   public native long    g1NumFreeRegions();
  82   public native int     g1RegionSize();
  83   public native Object[]    parseCommandLine(String commandline, DiagnosticCommand[] args);
  84 
  85   // NMT
  86   public native boolean NMTAllocTest();
  87   public native boolean NMTFreeTestMemory();
  88   public native boolean NMTWaitForDataMerge();
  89 
  90   // Compiler
  91   public native void    deoptimizeAll();
  92   public native boolean isMethodCompiled(Method method);
  93   public native boolean isMethodCompilable(Method method);
  94   public native boolean isMethodQueuedForCompilation(Method method);
  95   public native int     deoptimizeMethod(Method method);
  96   public native void    makeMethodNotCompilable(Method method);
  97   public native int     getMethodCompilationLevel(Method method);
  98   public native boolean setDontInlineMethod(Method method, boolean value);
  99   public native int     getCompileQueuesSize();
 100 
 101   //Intered strings
 102   public native boolean isInStringTable(String str);
 103 
 104   // force Full GC
 105   public native void fullGC();
 106 }