8275721: Name of UTC timezone in a locale changes depending on previous code

Reviewed-by: joehw

src/java.base/share/classes/sun/util/cldr/CLDRTimeZoneNameProviderImpl.java

@@ -82,7 +82,7 @@ public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
         }
 
         if (namesSuper != null) {
-            // CLDR's resource bundle has an translated entry for this id.
+            // CLDR's resource bundle has a translated entry for this id.
             // Fix up names if needed, either missing or no-inheritance
             namesSuper[INDEX_TZID] = id;
 
@@ -91,7 +91,7 @@ public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
                 case "":
                     // Fill in empty elements
                     deriveFallbackName(namesSuper, i, locale,
-                                       !TimeZone.getTimeZone(id).useDaylightTime());
+                                       TimeZone.getTimeZone(id).toZoneId().getRules().isFixedOffset());
                     break;
                 case NO_INHERITANCE_MARKER:
                     // CLDR's "no inheritance marker"
@@ -129,7 +129,7 @@ public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
 
     // Derive fallback time zone name according to LDML's logic
     private void deriveFallbackNames(String[] names, Locale locale) {
-        boolean noDST = !TimeZone.getTimeZone(names[0]).useDaylightTime();
+        boolean noDST = TimeZone.getTimeZone(names[0]).toZoneId().getRules().isFixedOffset();
 
         for (int i = INDEX_STD_LONG; i <= INDEX_GEN_SHORT; i++) {
             deriveFallbackName(names, i, locale, noDST);
@@ -149,13 +149,12 @@ public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
             return;
         }
 
-        // Check parent locale first
+        // Check parent locales first
         if (!exists(names, index)) {
             CLDRLocaleProviderAdapter clpa = (CLDRLocaleProviderAdapter)LocaleProviderAdapter.forType(Type.CLDR);
             var cands = clpa.getCandidateLocales("", locale);
-            if (cands.size() > 1) {
+            for (int i = 1; i < cands.size() ; i++) {
-                var parentLoc = cands.get(1); // immediate parent locale
+                String[] parentNames = super.getDisplayNameArray(id, cands.get(i));
-                String[] parentNames = super.getDisplayNameArray(id, parentLoc);
                 if (parentNames != null && !parentNames[index].isEmpty()) {
                     names[index] = parentNames[index];
                     return;
@@ -163,22 +162,6 @@ public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
             }
         }
 
-        // Check if COMPAT can substitute the name
-        if (LocaleProviderAdapter.getAdapterPreference().contains(Type.JRE)) {
-            String[] compatNames = (String[])LocaleProviderAdapter.forJRE()
-                .getLocaleResources(mapChineseLocale(locale))
-                .getTimeZoneNames(id);
-            if (compatNames != null) {
-                for (int i = INDEX_STD_LONG; i <= INDEX_GEN_SHORT; i++) {
-                    // Assumes COMPAT has no empty slots
-                    if (i == index || !exists(names, i)) {
-                        names[i] = compatNames[i];
-                    }
-                }
-                return;
-            }
-        }
-
         // Region Fallback
         if (regionFormatFallback(names, index, locale)) {
             return;
@@ -189,6 +172,19 @@ public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
             return;
         }
 
+        // Check if COMPAT can substitute the name
+        if (!exists(names, index) &&
+                LocaleProviderAdapter.getAdapterPreference().contains(Type.JRE)) {
+            String[] compatNames = (String[])LocaleProviderAdapter.forJRE()
+                    .getLocaleResources(mapChineseLocale(locale))
+                    .getTimeZoneNames(id);
+            if (compatNames != null) {
+                // Assumes COMPAT has no empty slots
+                names[index] = compatNames[index];
+                return;
+            }
+        }
+
         // last resort
         names[index] = toGMTFormat(id,
                                    index == INDEX_DST_LONG || index == INDEX_DST_SHORT,

test/jdk/sun/util/resources/TimeZone/ChineseTimeZoneNameTest.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 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
+ * 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 8275721
+ * @modules jdk.localedata
+ * @summary Checks Chinese time zone names for `UTC` using CLDR are consistent
+ * @run testng/othervm -Djava.locale.providers=CLDR,COMPAT ChineseTimeZoneNameTest
+ * @run testng/othervm -Djava.locale.providers=CLDR ChineseTimeZoneNameTest
+ */
+
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.Locale;
+
+import static org.testng.Assert.assertEquals;
+import org.testng.annotations.DataProvider;
+import org.testng.annotations.Test;
+
+@Test
+public class ChineseTimeZoneNameTest {
+
+    private static final Locale SIMPLIFIED_CHINESE = Locale.forLanguageTag("zh-Hans");
+    private static final Locale TRADITIONAL_CHINESE = Locale.forLanguageTag("zh-Hant");
+    private static final ZonedDateTime EPOCH_UTC =
+        ZonedDateTime.ofInstant(Instant.ofEpochSecond (0), ZoneId.of ("UTC"));
+
+    @DataProvider(name="locales")
+    Object[][] data() {
+        return new Object[][] {
+            {Locale.CHINESE,                        SIMPLIFIED_CHINESE},
+            {Locale.SIMPLIFIED_CHINESE,             SIMPLIFIED_CHINESE},
+            {Locale.forLanguageTag("zh-SG"),        SIMPLIFIED_CHINESE},
+            {Locale.forLanguageTag("zh-Hans-TW"),   SIMPLIFIED_CHINESE},
+            {Locale.forLanguageTag("zh-HK"),        TRADITIONAL_CHINESE},
+            {Locale.forLanguageTag("zh-MO"),        TRADITIONAL_CHINESE},
+            {Locale.TRADITIONAL_CHINESE,            TRADITIONAL_CHINESE},
+            {Locale.forLanguageTag("zh-Hant-CN"),   TRADITIONAL_CHINESE},
+        };
+    }
+
+    @Test(dataProvider="locales")
+    public void test_ChineseTimeZoneNames(Locale testLoc, Locale resourceLoc) {
+        assertEquals(DateTimeFormatter.ofPattern("z", testLoc).format(EPOCH_UTC),
+                DateTimeFormatter.ofPattern("z", resourceLoc).format(EPOCH_UTC));
+        assertEquals(DateTimeFormatter.ofPattern("zzzz", testLoc).format(EPOCH_UTC),
+                DateTimeFormatter.ofPattern("zzzz", resourceLoc).format(EPOCH_UTC));
+    }
+}