--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/runtime/ObjectSynchronizer.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,127 @@
+/*
+ * Copyright 2001-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+package sun.jvm.hotspot.runtime;
+
+import java.util.*;
+
+import sun.jvm.hotspot.oops.*;
+import sun.jvm.hotspot.utilities.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.types.*;
+
+public class ObjectSynchronizer {
+  static {
+    VM.registerVMInitializedObserver(new Observer() {
+        public void update(Observable o, Object data) {
+          initialize(VM.getVM().getTypeDataBase());
+        }
+      });
+  }
+
+  private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
+    Type type;
+    try {
+      type = db.lookupType("ObjectSynchronizer");
+      AddressField blockListField;
+      blockListField = type.getAddressField("gBlockList");
+      gBlockListAddr = blockListField.getValue();
+      blockSize = db.lookupIntConstant("ObjectSynchronizer::_BLOCKSIZE").intValue();
+    } catch (RuntimeException e) { }
+    type = db.lookupType("ObjectMonitor");
+    objectMonitorTypeSize = type.getSize();
+  }
+
+  public long identityHashValueFor(Oop obj) {
+    Mark mark = obj.getMark();
+    if (mark.isUnlocked()) {
+      // FIXME: can not generate marks in debugging system
+      return mark.hash();
+    } else if (mark.hasMonitor()) {
+      ObjectMonitor monitor = mark.monitor();
+      Mark temp = monitor.header();
+      return temp.hash();
+    } else {
+      if (Assert.ASSERTS_ENABLED) {
+        Assert.that(VM.getVM().isDebugging(), "Can not access displaced header otherwise");
+      }
+      if (mark.hasDisplacedMarkHelper()) {
+        Mark temp = mark.displacedMarkHelper();
+        return temp.hash();
+      }
+      // FIXME: can not do anything else here in debugging system
+      return 0;
+    }
+  }
+
+  public static Iterator objectMonitorIterator() {
+    if (gBlockListAddr != null) {
+      return new ObjectMonitorIterator();
+    } else {
+      return null;
+    }
+  }
+
+  private static class ObjectMonitorIterator implements Iterator {
+
+    // JVMTI raw monitors are not pointed by gBlockList
+    // and are not included by this Iterator. May add them later.
+
+    ObjectMonitorIterator() {
+      blockAddr = gBlockListAddr;
+      index = blockSize - 1;
+      block = new ObjectMonitor(blockAddr);
+    }
+
+    public boolean hasNext() {
+      return (index > 0 || block.freeNext() != null);
+    }
+
+    public Object next() {
+      Address addr;
+      if (index > 0) {
+        addr = blockAddr.addOffsetTo(index*objectMonitorTypeSize);
+      } else {
+        blockAddr = block.freeNext();
+        index = blockSize - 1;
+        addr = blockAddr.addOffsetTo(index*objectMonitorTypeSize);
+      }
+      index --;
+      return new ObjectMonitor(addr);
+    }
+
+    public void remove() {
+      throw new UnsupportedOperationException();
+    }
+
+    private ObjectMonitor block;
+    private int index;
+    private Address blockAddr;
+  }
+
+  private static Address gBlockListAddr;
+  private static int blockSize;
+  private static long objectMonitorTypeSize;
+
+}