--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/utilities/BasicHashtableEntry.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2003-2004 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.utilities;
+
+import java.util.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.oops.Oop;
+import sun.jvm.hotspot.oops.ObjectHeap;
+import sun.jvm.hotspot.types.*;
+import sun.jvm.hotspot.runtime.*;
+
+public class BasicHashtableEntry 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("BasicHashtableEntry");
+    hashField      = type.getCIntegerField("_hash");
+    nextField      = type.getAddressField("_next");
+  }
+
+  // Fields
+  private static CIntegerField hashField;
+  private static AddressField  nextField;
+
+  // Accessors
+  public long hash() {
+    return hashField.getValue(addr) & 0xFFFFFFFFL;
+  }
+
+  private long nextAddressValue() {
+    Debugger dbg = VM.getVM().getDebugger();
+    Address nextValue = nextField.getValue(addr);
+    return (nextValue != null) ? dbg.getAddressValue(nextValue) : 0L;
+  }
+
+  public boolean isShared() {
+    return (nextAddressValue() & 1L) != 0;
+  }
+
+  public BasicHashtableEntry next() {
+    Address nextValue = nextField.getValue(addr);
+    Address next = (nextValue != null)? nextValue.andWithMask(-2L) : null;
+    // using this.getClass so that return type will be as expected in
+    // subclass context. But, because we can't use covariant return type
+    // caller has to use this next and cast the result to correct type.
+    return (BasicHashtableEntry) VMObjectFactory.newObject(this.getClass(), next);
+  }
+
+  public BasicHashtableEntry(Address addr) {
+    super(addr);
+  }
+}