--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/memory/FreeChunk.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2003 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.memory;
+
+import java.util.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.types.*;
+import sun.jvm.hotspot.runtime.*;
+
+public class FreeChunk extends VMObject {
+   static {
+      VM.registerVMInitializedObserver(new Observer() {
+         public void update(Observable o, Object data) {
+            initialize(VM.getVM().getTypeDataBase());
+         }
+      });
+   }
+
+   private static synchronized void initialize(TypeDataBase db) {
+      Type type = db.lookupType("FreeChunk");
+      nextField = type.getAddressField("_next");
+      prevField = type.getAddressField("_prev");
+      sizeField = type.getCIntegerField("_size");
+   }
+
+   // Fields
+   private static AddressField nextField;
+   private static AddressField prevField;
+   private static CIntegerField sizeField;
+
+   // Accessors
+   public FreeChunk next() {
+      return (FreeChunk) VMObjectFactory.newObject(FreeChunk.class, nextField.getValue(addr));
+   }
+
+   public FreeChunk prev() {
+      Address prev = prevField.getValue(addr).andWithMask(~0x3);
+      return (FreeChunk) VMObjectFactory.newObject(FreeChunk.class, prev);
+   }
+
+   public long size() {
+      return sizeField.getValue(addr);
+   }
+
+   public FreeChunk(Address addr) {
+      super(addr);
+   }
+
+   public static boolean secondWordIndicatesFreeChunk(long word) {
+      return (word & 0x1L) == 0x1L;
+   }
+
+   public boolean isFree() {
+      Debugger dbg = VM.getVM().getDebugger();
+      Address prev = prevField.getValue(addr);
+      return secondWordIndicatesFreeChunk(dbg.getAddressValue(prev));
+   }
+}