8177552: Compact Number Formatting support

Reviewed-by: naoto, rriggs

src/java.base/share/classes/sun/util/locale/provider/LocaleResources.java

@@ -43,6 +43,7 @@ package sun.util.locale.provider;
 import java.lang.ref.ReferenceQueue;
 import java.lang.ref.SoftReference;
 import java.text.MessageFormat;
+import java.text.NumberFormat;
 import java.util.Calendar;
 import java.util.HashSet;
 import java.util.LinkedHashSet;
@@ -88,6 +89,7 @@ public class LocaleResources {
     private static final String ZONE_IDS_CACHEKEY = "ZID";
     private static final String CALENDAR_NAMES = "CALN.";
     private static final String NUMBER_PATTERNS_CACHEKEY = "NP";
+    private static final String COMPACT_NUMBER_PATTERNS_CACHEKEY = "CNP";
     private static final String DATE_TIME_PATTERN = "DTP.";
 
     // TimeZoneNamesBundle exemplar city prefix
@@ -478,6 +480,32 @@ public class LocaleResources {
         return numberPatterns;
     }
 
+    /**
+     * Returns the compact number format patterns.
+     * @param formatStyle the style for formatting a number
+     * @return an array of compact number patterns
+     */
+    @SuppressWarnings("unchecked")
+    public String[] getCNPatterns(NumberFormat.Style formatStyle) {
+
+        Objects.requireNonNull(formatStyle);
+        String[] compactNumberPatterns = null;
+        removeEmptyReferences();
+        String width = (formatStyle == NumberFormat.Style.LONG) ? "long" : "short";
+        String cacheKey = width + "." + COMPACT_NUMBER_PATTERNS_CACHEKEY;
+        ResourceReference data = cache.get(cacheKey);
+        if (data == null || ((compactNumberPatterns
+                = (String[]) data.get()) == null)) {
+            ResourceBundle resource = localeData.getNumberFormatData(locale);
+            compactNumberPatterns = (String[]) resource
+                    .getObject(width + ".CompactNumberPatterns");
+            cache.put(cacheKey, new ResourceReference(cacheKey,
+                    (Object) compactNumberPatterns, referenceQueue));
+        }
+        return compactNumberPatterns;
+    }
+
+
     /**
      * Returns the FormatData resource bundle of this LocaleResources.
      * The FormatData should be used only for accessing extra

src/java.base/share/classes/sun/util/locale/provider/NumberFormatProviderImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 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
@@ -40,12 +40,14 @@
 
 package sun.util.locale.provider;
 
+import java.text.CompactNumberFormat;
 import java.text.DecimalFormat;
 import java.text.DecimalFormatSymbols;
 import java.text.NumberFormat;
 import java.text.spi.NumberFormatProvider;
 import java.util.Currency;
 import java.util.Locale;
+import java.util.Objects;
 import java.util.Set;
 
 /**
@@ -225,6 +227,49 @@ public class NumberFormatProviderImpl extends NumberFormatProvider implements Av
         }
     }
 
+    /**
+     * Returns a new {@code NumberFormat} instance which formats
+     * a number in its compact form for the specified
+     * {@code locale} and {@code formatStyle}.
+     *
+     * @param locale the desired locale
+     * @param formatStyle the style for formatting a number
+     * @throws NullPointerException if {@code locale} or {@code formatStyle}
+     *     is {@code null}
+     * @throws IllegalArgumentException if {@code locale} isn't
+     *     one of the locales returned from
+     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
+     *     getAvailableLocales()}.
+     * @return a compact number formatter
+     *
+     * @see java.text.NumberFormat#getCompactNumberInstance(Locale,
+     *                      NumberFormat.Style)
+     * @since 12
+     */
+    @Override
+    public NumberFormat getCompactNumberInstance(Locale locale,
+            NumberFormat.Style formatStyle) {
+
+        Objects.requireNonNull(locale);
+        Objects.requireNonNull(formatStyle);
+
+        // Check for region override
+        Locale override = locale.getUnicodeLocaleType("nu") == null
+                ? CalendarDataUtility.findRegionOverride(locale)
+                : locale;
+
+        LocaleProviderAdapter adapter = LocaleProviderAdapter.forType(type);
+        LocaleResources resource = adapter.getLocaleResources(override);
+
+        String[] numberPatterns = resource.getNumberPatterns();
+        DecimalFormatSymbols symbols = DecimalFormatSymbols.getInstance(override);
+        String[] cnPatterns = resource.getCNPatterns(formatStyle);
+
+        CompactNumberFormat format = new CompactNumberFormat(numberPatterns[0],
+                symbols, cnPatterns);
+        return format;
+    }
+
     @Override
     public Set<String> getAvailableLanguageTags() {
         return langtags;