8171049: Era.getDisplayName doesn't work with non-IsoChronology

Reviewed-by: naoto
Contributed-by: deepak.kejriwal@oracle.com

src/share/classes/java/time/chrono/HijrahEra.java

@@ -64,10 +64,13 @@ package java.time.chrono;
 import static java.time.temporal.ChronoField.ERA;
 
 import java.time.DateTimeException;
+import java.time.format.DateTimeFormatterBuilder;
+import java.time.format.TextStyle;
 import java.time.temporal.ChronoField;
 import java.time.temporal.TemporalField;
 import java.time.temporal.UnsupportedTemporalTypeException;
 import java.time.temporal.ValueRange;
+import java.util.Locale;
 
 /**
  * An era in the Hijrah calendar system.
@@ -155,4 +158,18 @@ public enum HijrahEra implements Era {
         return Era.super.range(field);
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param style {@inheritDoc}
+     * @param locale {@inheritDoc}
+     */
+    @Override
+    public String getDisplayName(TextStyle style, Locale locale) {
+        return new DateTimeFormatterBuilder()
+            .appendText(ERA, style)
+            .toFormatter(locale)
+            .withChronology(HijrahChronology.INSTANCE)
+            .format(HijrahDate.now());
+}
 }

src/share/classes/java/time/chrono/JapaneseEra.java

@@ -73,6 +73,7 @@ import java.io.ObjectStreamException;
 import java.io.Serializable;
 import java.time.DateTimeException;
 import java.time.LocalDate;
+import java.time.format.DateTimeFormatterBuilder;
 import java.time.format.TextStyle;
 import java.time.temporal.ChronoField;
 import java.time.temporal.TemporalField;
@@ -252,7 +253,12 @@ public final class JapaneseEra
             Objects.requireNonNull(locale, "locale");
             return style.asNormal() == TextStyle.NARROW ? getAbbreviation() : getName();
         }
-        return Era.super.getDisplayName(style, locale);
+
+        return new DateTimeFormatterBuilder()
+            .appendText(ERA, style)
+            .toFormatter(locale)
+            .withChronology(JapaneseChronology.INSTANCE)
+            .format(this == MEIJI ? MEIJI_6_ISODATE : since);
     }
 
     //-----------------------------------------------------------------------

src/share/classes/java/time/chrono/MinguoEra.java

@@ -61,7 +61,12 @@
  */
 package java.time.chrono;
 
+import static java.time.temporal.ChronoField.ERA;
+
 import java.time.DateTimeException;
+import java.time.format.DateTimeFormatterBuilder;
+import java.time.format.TextStyle;
+import java.util.Locale;
 
 /**
  * An era in the Minguo calendar system.
@@ -152,4 +157,19 @@ public enum MinguoEra implements Era {
         return ordinal();
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param style {@inheritDoc}
+     * @param locale {@inheritDoc}
+     */
+    @Override
+    public String getDisplayName(TextStyle style, Locale locale) {
+        return new DateTimeFormatterBuilder()
+            .appendText(ERA, style)
+            .toFormatter(locale)
+            .withChronology(MinguoChronology.INSTANCE)
+            .format(this == ROC ? MinguoDate.of(1, 1, 1) : MinguoDate.of(0, 1, 1));
+}
+
 }

src/share/classes/java/time/chrono/ThaiBuddhistEra.java

@@ -61,7 +61,12 @@
  */
 package java.time.chrono;
 
+import static java.time.temporal.ChronoField.ERA;
+
 import java.time.DateTimeException;
+import java.time.format.DateTimeFormatterBuilder;
+import java.time.format.TextStyle;
+import java.util.Locale;
 
 /**
  * An era in the Thai Buddhist calendar system.
@@ -152,4 +157,19 @@ public enum ThaiBuddhistEra implements Era {
         return ordinal();
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param style {@inheritDoc}
+     * @param locale {@inheritDoc}
+     */
+    @Override
+    public String getDisplayName(TextStyle style, Locale locale) {
+        return new DateTimeFormatterBuilder()
+            .appendText(ERA, style)
+            .toFormatter(locale)
+            .withChronology(ThaiBuddhistChronology.INSTANCE)
+            .format(this == BE ? ThaiBuddhistDate.of(1, 1, 1) : ThaiBuddhistDate.of(0, 1, 1));
+}
+
 }

test/java/time/test/java/time/chrono/TestEraDisplayName.java

+/*
+ * Copyright (c) 2018, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 test.java.time.chrono;
+
+import java.time.*;
+import java.time.chrono.*;
+import java.time.format.*;
+import java.util.Locale;
+
+import org.testng.annotations.DataProvider;
+import org.testng.annotations.Test;
+import static org.testng.Assert.assertEquals;
+
+/**
+ * Tests Era.getDisplayName() correctly returns the name based on each
+ * chrono implementation.
+ * Note: The exact result may depend on locale data provider's implementation.
+ *
+ * @bug 8171049
+ * @run testng/othervm -Djava.locale.providers=CLDR TestEraDisplayName
+ */
+@Test
+public class TestEraDisplayName {
+    private static final Locale THAI = Locale.forLanguageTag("th-TH");
+    private static final Locale EGYPT = Locale.forLanguageTag("ar-EG");
+
+    @DataProvider(name="eraDisplayName")
+    Object[][] eraDisplayName() {
+        return new Object[][] {
+            // Era, text style, displyay locale, expected name
+            // IsoEra
+            { IsoEra.BCE,   TextStyle.FULL,     Locale.US,      "Before Christ" },
+            { IsoEra.CE,    TextStyle.FULL,     Locale.US,      "Anno Domini" },
+            { IsoEra.BCE,   TextStyle.FULL,     Locale.JAPAN,   "\u7d00\u5143\u524d" },
+            { IsoEra.CE,    TextStyle.FULL,     Locale.JAPAN,   "\u897f\u66a6" },
+            { IsoEra.BCE,   TextStyle.SHORT,    Locale.US,      "BC" },
+            { IsoEra.CE,    TextStyle.SHORT,    Locale.US,      "AD" },
+            { IsoEra.BCE,   TextStyle.SHORT,    Locale.JAPAN,   "\u7d00\u5143\u524d" },
+            { IsoEra.CE,    TextStyle.SHORT,    Locale.JAPAN,   "\u897f\u66a6" },
+            { IsoEra.BCE,   TextStyle.NARROW,   Locale.US,      "B" },
+            { IsoEra.CE,    TextStyle.NARROW,   Locale.US,      "A" },
+            { IsoEra.BCE,   TextStyle.NARROW,   Locale.JAPAN,   "B" },
+            { IsoEra.CE,    TextStyle.NARROW,   Locale.JAPAN,   "A" },
+
+            // JapaneseEra
+            { JapaneseEra.MEIJI,    TextStyle.FULL,     Locale.US,      "Meiji" },
+            { JapaneseEra.TAISHO,   TextStyle.FULL,     Locale.US,      "Taisho" },
+            { JapaneseEra.SHOWA,    TextStyle.FULL,     Locale.US,      "Showa" },
+            { JapaneseEra.HEISEI,   TextStyle.FULL,     Locale.US,      "Heisei" },
+            { JapaneseEra.MEIJI,    TextStyle.FULL,     Locale.JAPAN,   "\u660e\u6cbb" },
+            { JapaneseEra.TAISHO,   TextStyle.FULL,     Locale.JAPAN,   "\u5927\u6b63" },
+            { JapaneseEra.SHOWA,    TextStyle.FULL,     Locale.JAPAN,   "\u662d\u548c" },
+            { JapaneseEra.HEISEI,   TextStyle.FULL,     Locale.JAPAN,   "\u5e73\u6210" },
+            { JapaneseEra.MEIJI,    TextStyle.SHORT,    Locale.US,      "Meiji" },
+            { JapaneseEra.TAISHO,   TextStyle.SHORT,    Locale.US,      "Taisho" },
+            { JapaneseEra.SHOWA,    TextStyle.SHORT,    Locale.US,      "Showa" },
+            { JapaneseEra.HEISEI,   TextStyle.SHORT,    Locale.US,      "Heisei" },
+            { JapaneseEra.MEIJI,    TextStyle.SHORT,    Locale.JAPAN,   "\u660e\u6cbb" },
+            { JapaneseEra.TAISHO,   TextStyle.SHORT,    Locale.JAPAN,   "\u5927\u6b63" },
+            { JapaneseEra.SHOWA,    TextStyle.SHORT,    Locale.JAPAN,   "\u662d\u548c" },
+            { JapaneseEra.HEISEI,   TextStyle.SHORT,    Locale.JAPAN,   "\u5e73\u6210" },
+            { JapaneseEra.MEIJI,    TextStyle.NARROW,   Locale.US,      "M" },
+            { JapaneseEra.TAISHO,   TextStyle.NARROW,   Locale.US,      "T" },
+            { JapaneseEra.SHOWA,    TextStyle.NARROW,   Locale.US,      "S" },
+            { JapaneseEra.HEISEI,   TextStyle.NARROW,   Locale.US,      "H" },
+            { JapaneseEra.MEIJI,    TextStyle.NARROW,   Locale.JAPAN,   "M" },
+            { JapaneseEra.TAISHO,   TextStyle.NARROW,   Locale.JAPAN,   "T" },
+            { JapaneseEra.SHOWA,    TextStyle.NARROW,   Locale.JAPAN,   "S" },
+            { JapaneseEra.HEISEI,   TextStyle.NARROW,   Locale.JAPAN,   "H" },
+
+            // ThaiBuddhistEra
+            { ThaiBuddhistEra.BEFORE_BE,    TextStyle.FULL, Locale.US,      "BC" },
+            { ThaiBuddhistEra.BE,           TextStyle.FULL, Locale.US,      "B.E." },
+            { ThaiBuddhistEra.BEFORE_BE,    TextStyle.FULL, THAI,           "BC" },
+            { ThaiBuddhistEra.BE,           TextStyle.FULL, THAI,
+                "\u0e1e\u0e38\u0e17\u0e18\u0e28\u0e31\u0e01\u0e23\u0e32\u0e0a" },
+            { ThaiBuddhistEra.BEFORE_BE,    TextStyle.SHORT, Locale.US,     "BC" },
+            { ThaiBuddhistEra.BE,           TextStyle.SHORT, Locale.US,     "B.E." },
+            { ThaiBuddhistEra.BEFORE_BE,    TextStyle.SHORT, THAI,
+                "\u0e1b\u0e35\u0e01\u0e48\u0e2d\u0e19\u0e04\u0e23\u0e34\u0e2a" +
+                "\u0e15\u0e4c\u0e01\u0e32\u0e25\u0e17\u0e35\u0e48" },
+            { ThaiBuddhistEra.BE,           TextStyle.SHORT, THAI,  "\u0e1e.\u0e28." },
+            { ThaiBuddhistEra.BEFORE_BE,    TextStyle.NARROW, Locale.US,    "BC" },
+            { ThaiBuddhistEra.BE,           TextStyle.NARROW, Locale.US,    "B.E." },
+            { ThaiBuddhistEra.BEFORE_BE,    TextStyle.NARROW, THAI,         "BC" },
+            { ThaiBuddhistEra.BE,           TextStyle.NARROW, THAI,         "B.E." },
+
+            // MinguoEra
+            { MinguoEra.BEFORE_ROC, TextStyle.FULL,     Locale.US,      "Before R.O.C." },
+            { MinguoEra.ROC,        TextStyle.FULL,     Locale.US,      "R.O.C." },
+            { MinguoEra.BEFORE_ROC, TextStyle.FULL,     Locale.TAIWAN,  "\u6c11\u570b\u524d" },
+            { MinguoEra.ROC,        TextStyle.FULL,     Locale.TAIWAN,  "\u6c11\u570b" },
+            { MinguoEra.BEFORE_ROC, TextStyle.SHORT,    Locale.US,      "Before R.O.C." },
+            { MinguoEra.ROC,        TextStyle.SHORT,    Locale.US,      "R.O.C." },
+            { MinguoEra.BEFORE_ROC, TextStyle.SHORT,    Locale.TAIWAN,  "\u6c11\u570b\u524d" },
+            { MinguoEra.ROC,        TextStyle.SHORT,    Locale.TAIWAN,  "\u6c11\u570b" },
+            { MinguoEra.BEFORE_ROC, TextStyle.NARROW,   Locale.US,      "0" },
+            { MinguoEra.ROC,        TextStyle.NARROW,   Locale.US,      "1" },
+            { MinguoEra.BEFORE_ROC, TextStyle.NARROW,   Locale.TAIWAN,  "0" },
+            { MinguoEra.ROC,        TextStyle.NARROW,   Locale.TAIWAN,  "1" },
+
+            // HijrahEra
+            { HijrahEra.AH, TextStyle.FULL,     Locale.US,  "AH" },
+            { HijrahEra.AH, TextStyle.FULL,     EGYPT,      "\u0647\u0640" },
+            { HijrahEra.AH, TextStyle.SHORT,    Locale.US,  "AH" },
+            { HijrahEra.AH, TextStyle.SHORT,    EGYPT,      "\u0647\u0640" },
+            { HijrahEra.AH, TextStyle.NARROW,   Locale.US,  "1" },
+            { HijrahEra.AH, TextStyle.NARROW,   EGYPT,      "1" },
+        };
+    }
+
+    @Test(dataProvider="eraDisplayName")
+    public void test_eraDisplayName(Era era, TextStyle style, Locale locale, String expected) {
+        assertEquals(era.getDisplayName(style, locale), expected);
+    }
+}