--- a/jdk/src/share/classes/sun/util/BuddhistCalendar.java	Wed Dec 08 13:02:22 2010 +0900
+++ b/jdk/src/share/classes/sun/util/BuddhistCalendar.java	Wed Dec 08 13:09:29 2010 +0900
@@ -25,6 +25,8 @@
 
 package sun.util;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
 import java.util.Calendar;
 import java.util.GregorianCalendar;
 import java.util.HashMap;
@@ -42,7 +44,7 @@
 
     private static final long serialVersionUID = -8527488697350388578L;
 
-    private static final int buddhistOffset = 543;
+    private static final int BUDDHIST_YEAR_OFFSET = 543;
 
 ///////////////
 // Constructors
@@ -103,7 +105,7 @@
      * Generates the hash code for the BuddhistCalendar object
      */
     public int hashCode() {
-        return super.hashCode() ^ buddhistOffset;
+        return super.hashCode() ^ BUDDHIST_YEAR_OFFSET;
     }
 
     /**
@@ -141,6 +143,8 @@
     public void add(int field, int amount)
     {
         int savedYearOffset = yearOffset;
+        // To let the superclass calculate date-time values correctly,
+        // temporarily make this GregorianCalendar.
         yearOffset = 0;
         try {
             super.add(field, amount);
@@ -159,6 +163,8 @@
     public void roll(int field, int amount)
     {
         int savedYearOffset = yearOffset;
+        // To let the superclass calculate date-time values correctly,
+        // temporarily make this GregorianCalendar.
         yearOffset = 0;
         try {
             super.roll(field, amount);
@@ -246,6 +252,8 @@
      */
     public int getActualMaximum(int field) {
         int savedYearOffset = yearOffset;
+        // To let the superclass calculate date-time values correctly,
+        // temporarily make this GregorianCalendar.
         yearOffset = 0;
         try {
             return super.getActualMaximum(field);
@@ -275,11 +283,16 @@
         // Skip the year number
         while (Character.isDigit(s.charAt(p++)))
             ;
-        int year = internalGet(YEAR) + buddhistOffset;
+        int year = internalGet(YEAR) + BUDDHIST_YEAR_OFFSET;
         sb.append(year).append(s.substring(p - 1));
         return sb.toString();
     }
 
-    private transient int yearOffset = buddhistOffset;
+    private transient int yearOffset = BUDDHIST_YEAR_OFFSET;
 
+    private void readObject(ObjectInputStream stream)
+        throws IOException, ClassNotFoundException {
+        stream.defaultReadObject();
+        yearOffset = BUDDHIST_YEAR_OFFSET;
+    }
 }

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/sun/util/calendar/Bug6653944.java	Wed Dec 08 13:09:29 2010 +0900
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2010, 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.
+ */
+
+/*
+ *@test
+ *@bug 6653944
+ *@summary Deserialization tests for YEAR calculcations
+ */
+
+import java.io.*;
+import java.util.*;
+
+public class Bug6653944 {
+    private static int errorCount = 0;
+
+    public static void main(String[] args) throws Exception {
+        Calendar buddhist = Calendar.getInstance(new Locale("th", "TH"));
+        int expectedYear = buddhist.get(Calendar.YEAR);
+
+        Calendar deserialized = (Calendar) deserialize(serialize(buddhist));
+        compare(deserialized, buddhist);
+
+        int deserializedYear = deserialized.get(Calendar.YEAR);
+        compare(deserializedYear, expectedYear);
+
+        // test add(YEAR, n).
+        buddhist.add(Calendar.YEAR, 12);
+        expectedYear = buddhist.get(Calendar.YEAR);
+        deserialized.add(Calendar.YEAR, 12);
+        deserializedYear = deserialized.get(Calendar.YEAR);
+        compare(deserialized, buddhist);
+        compare(deserializedYear, expectedYear);
+
+        if (errorCount > 0) {
+            throw new RuntimeException("Bug6653944: failed");
+        }
+    }
+
+    private static void compare(int got, int expected) {
+        if (got != expected) {
+            System.err.println("got " + got + ", expected " + expected);
+            errorCount++;
+        }
+    }
+
+    private static void compare(Calendar got, Calendar expected) {
+        if (!got.equals(expected)) {
+            System.err.println("got " + got + ", expected " + expected);
+            errorCount++;
+        }
+    }
+
+    private static byte[] serialize(Serializable obj) throws Exception {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        ObjectOutputStream oos = new ObjectOutputStream(baos);
+        oos.writeObject(obj);
+        oos.close();
+        return baos.toByteArray();
+    }
+
+    private static Object deserialize(byte[] data) throws Exception {
+        ByteArrayInputStream bais = new ByteArrayInputStream(data);
+        ObjectInputStream ois = new ObjectInputStream(bais);
+        return ois.readObject();
+    }
+}