From c4b3d62c7fbf9567404be28eaf9635bad435e06b Mon Sep 17 00:00:00 2001
From: Yoshiki Sato <ysatowse@openjdk.org>
Date: Wed, 29 Sep 2021 13:04:44 +0000
Subject: [PATCH] 8273924: ArrayIndexOutOfBoundsException thrown in
 java.util.JapaneseImperialCalendar.add()

Backport-of: d39aad92308fbc28bd2de164e331062ebf62da85
---
 .../sun/util/calendar/BaseCalendar.java       |  6 +++++-
 .../CalendarTestScripts/JapaneseTests.java    |  2 +-
 .../japanese/japanese_add.cts                 | 20 +++++++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/src/java.base/share/classes/sun/util/calendar/BaseCalendar.java b/src/java.base/share/classes/sun/util/calendar/BaseCalendar.java
index 3c07431274c..8a7ffc6344d 100644
--- a/src/java.base/share/classes/sun/util/calendar/BaseCalendar.java
+++ b/src/java.base/share/classes/sun/util/calendar/BaseCalendar.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2021, 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
@@ -277,6 +277,10 @@ void normalizeMonth(CalendarDate date) {
             long xm = 1L - month;
             year -= (int)((xm / 12) + 1);
             month = 13 - (xm % 12);
+            if (month == 13) {
+                year++;
+                month = 1;
+            }
             bdate.setNormalizedYear(year);
             bdate.setMonth((int) month);
         } else if (month > DECEMBER) {
diff --git a/test/jdk/java/util/Calendar/CalendarTestScripts/JapaneseTests.java b/test/jdk/java/util/Calendar/CalendarTestScripts/JapaneseTests.java
index 403e483affa..4f21b33baaa 100644
--- a/test/jdk/java/util/Calendar/CalendarTestScripts/JapaneseTests.java
+++ b/test/jdk/java/util/Calendar/CalendarTestScripts/JapaneseTests.java
@@ -24,7 +24,7 @@
 /*
  * @test
  * @summary tests Japanese Calendar.
- * @bug 4609228 8187649
+ * @bug 4609228 8187649 8273924
  * @modules java.base/sun.util
  *          java.base/sun.util.calendar
  * @compile
diff --git a/test/jdk/java/util/Calendar/CalendarTestScripts/japanese/japanese_add.cts b/test/jdk/java/util/Calendar/CalendarTestScripts/japanese/japanese_add.cts
index b698b785815..c0f6be479a1 100644
--- a/test/jdk/java/util/Calendar/CalendarTestScripts/japanese/japanese_add.cts
+++ b/test/jdk/java/util/Calendar/CalendarTestScripts/japanese/japanese_add.cts
@@ -354,6 +354,26 @@ test add MONTH
 #	check date Heisei $max Aug 16
 #	check timeofday 23 59 59 999
 
+#	JDK-8273924
+	set date Reiwa 2 Mar 1
+	add month -10
+	check date Reiwa 1 May 1
+	set date Reiwa 2 Mar 1
+	add month -11
+	check date Heisei 31 Apr 1
+	set date Reiwa 2 Mar 1
+	add month -12
+	check date Heisei 31 Mar 1
+	set date Reiwa 2 Mar 1
+	add month -13
+	check date Heisei 31 Feb 1
+	set date Reiwa 2 Mar 1
+	add month -14
+	check date Heisei 31 Jan 1
+	set date Reiwa 2 Mar 1
+	add month -15
+	check date Heisei 30 Dec 1
+
 test add WEEK_OF_YEAR
     use jcal
 	clear all