--- /dev/null	2017-09-26 23:34:53.308187500 +0900
+++ new/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/g1/HeapRegionType.java	2017-09-26 23:52:01.681813751 +0900
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+package sun.jvm.hotspot.gc.g1;
+
+import java.util.Observable;
+import java.util.Observer;
+import sun.jvm.hotspot.debugger.Address;
+import sun.jvm.hotspot.runtime.VM;
+import sun.jvm.hotspot.runtime.VMObject;
+import sun.jvm.hotspot.types.CIntegerField;
+import sun.jvm.hotspot.types.Type;
+import sun.jvm.hotspot.types.TypeDataBase;
+
+// Mirror class for HeapRegionType. Currently we don't actually include
+// any of its fields but only iterate over it.
+
+public class HeapRegionType extends VMObject {
+
+    private static int freeTag;
+
+    private static int youngMask;
+
+    private static int humongousMask;
+
+    private static int pinnedMask;
+
+    private static int oldMask;
+
+    private static CIntegerField tagField;
+
+    private int tag;
+
+    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("HeapRegionType");
+
+        tagField = type.getCIntegerField("_tag");
+
+        youngMask = db.lookupIntConstant("HeapRegionType::YoungMask");
+        humongousMask = db.lookupIntConstant("HeapRegionType::HumongousMask");
+        oldMask = db.lookupIntConstant("HeapRegionType::OldMask");
+    }
+
+    public boolean isFree() {
+        return tagField.getValue(addr) == freeTag;
+    }
+
+    public boolean isYoung() {
+        return (tagField.getValue(addr) & youngMask) != 0;
+    }
+
+    public boolean isHumongous() {
+        return (tagField.getValue(addr) & humongousMask) != 0;
+    }
+
+    public boolean isPinned() {
+        return (tagField.getValue(addr) & pinnedMask) != 0;
+    }
+
+    public boolean isOld() {
+        return (tagField.getValue(addr) & oldMask) != 0;
+    }
+
+    public HeapRegionType(Address addr) {
+        super(addr);
+    }
+}