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package sun.util.locale.provider;

import java.lang.ref.SoftReference;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.spi.TimeZoneNameProvider;
import sun.util.calendar.ZoneInfo;
import sun.util.cldr.CLDRLocaleProviderAdapter;
import static sun.util.locale.provider.LocaleProviderAdapter.Type;

Utility class that deals with the localized time zone names
Author:Naoto Sato, Masayoshi Okutsu
/** * Utility class that deals with the localized time zone names * * @author Naoto Sato * @author Masayoshi Okutsu */
public final class TimeZoneNameUtility {
cache to hold time zone localized strings. Keyed by Locale
/** * cache to hold time zone localized strings. Keyed by Locale */
private static final ConcurrentHashMap<Locale, SoftReference<String[][]>> cachedZoneData = new ConcurrentHashMap<>();
Cache for managing display names per timezone per locale The structure is: Map(key=id, value=SoftReference(Map(key=locale, value=displaynames)))
/** * Cache for managing display names per timezone per locale * The structure is: * Map(key=id, value=SoftReference(Map(key=locale, value=displaynames))) */
private static final Map<String, SoftReference<Map<Locale, String[]>>> cachedDisplayNames = new ConcurrentHashMap<>();
get time zone localized strings. Enumerate all keys.
/** * get time zone localized strings. Enumerate all keys. */
public static String[][] getZoneStrings(Locale locale) { String[][] zones; SoftReference<String[][]> data = cachedZoneData.get(locale); if (data == null || ((zones = data.get()) == null)) { zones = loadZoneStrings(locale); data = new SoftReference<>(zones); cachedZoneData.put(locale, data); } return zones; } private static String[][] loadZoneStrings(Locale locale) { // If the provider is a TimeZoneNameProviderImpl, call its getZoneStrings // in order to avoid per-ID retrieval. LocaleProviderAdapter adapter = LocaleProviderAdapter.getAdapter(TimeZoneNameProvider.class, locale); TimeZoneNameProvider provider = adapter.getTimeZoneNameProvider(); if (provider instanceof TimeZoneNameProviderImpl) { String[][] zoneStrings = ((TimeZoneNameProviderImpl)provider).getZoneStrings(locale); if (zoneStrings.length == 0 && locale.equals(Locale.ROOT)) { // Unlike other *Name provider, zoneStrings search won't do the fallback // name search. If the ResourceBundle found for the root locale contains no // zoneStrings, just use the one for English, assuming English bundle // contains all the tzids and their names. zoneStrings= getZoneStrings(Locale.ENGLISH); } return zoneStrings; } // Performs per-ID retrieval. Set<String> zoneIDs = LocaleProviderAdapter.forJRE().getLocaleResources(locale).getZoneIDs(); List<String[]> zones = new LinkedList<>(); for (String key : zoneIDs) { String[] names = retrieveDisplayNamesImpl(key, locale); if (names != null) { zones.add(names); } } String[][] zonesArray = new String[zones.size()][]; return zones.toArray(zonesArray); }
Retrieve display names for a time zone ID.
/** * Retrieve display names for a time zone ID. */
public static String[] retrieveDisplayNames(String id, Locale locale) { Objects.requireNonNull(id); Objects.requireNonNull(locale); return retrieveDisplayNamesImpl(id, locale); }
Retrieves a generic time zone display name for a time zone ID.
Params:
  • id – time zone ID
  • style – TimeZone.LONG or TimeZone.SHORT
  • locale – desired Locale
Returns:the requested generic time zone display name, or null if not found.
/** * Retrieves a generic time zone display name for a time zone ID. * * @param id time zone ID * @param style TimeZone.LONG or TimeZone.SHORT * @param locale desired Locale * @return the requested generic time zone display name, or null if not found. */
public static String retrieveGenericDisplayName(String id, int style, Locale locale) { String[] names = retrieveDisplayNamesImpl(id, locale); if (Objects.nonNull(names)) { return names[6 - style]; } else { return null; } }
Retrieves a standard or daylight-saving time name for the given time zone ID.
Params:
  • id – time zone ID
  • daylight – true for a daylight saving time name, or false for a standard time name
  • style – TimeZone.LONG or TimeZone.SHORT
  • locale – desired Locale
Returns:the requested time zone name, or null if not found.
/** * Retrieves a standard or daylight-saving time name for the given time zone ID. * * @param id time zone ID * @param daylight true for a daylight saving time name, or false for a standard time name * @param style TimeZone.LONG or TimeZone.SHORT * @param locale desired Locale * @return the requested time zone name, or null if not found. */
public static String retrieveDisplayName(String id, boolean daylight, int style, Locale locale) { String[] names = retrieveDisplayNamesImpl(id, locale); if (Objects.nonNull(names)) { return names[(daylight ? 4 : 2) - style]; } else { return null; } }
Converts the time zone id from LDML's 5-letter id to tzdb's id
Params:
  • shortID – time zone short ID defined in LDML
Returns:the tzdb's time zone ID
/** * Converts the time zone id from LDML's 5-letter id to tzdb's id * * @param shortID time zone short ID defined in LDML * @return the tzdb's time zone ID */
public static Optional<String> convertLDMLShortID(String shortID) { return canonicalTZID(shortID); }
Returns the canonical ID for the given ID
/** * Returns the canonical ID for the given ID */
public static Optional<String> canonicalTZID(String id) { return ((CLDRLocaleProviderAdapter)LocaleProviderAdapter.forType(Type.CLDR)) .canonicalTZID(id); } private static String[] retrieveDisplayNamesImpl(String id, Locale locale) { LocaleServiceProviderPool pool = LocaleServiceProviderPool.getPool(TimeZoneNameProvider.class); String[] names; Map<Locale, String[]> perLocale = null; SoftReference<Map<Locale, String[]>> ref = cachedDisplayNames.get(id); if (Objects.nonNull(ref)) { perLocale = ref.get(); if (Objects.nonNull(perLocale)) { names = perLocale.get(locale); if (Objects.nonNull(names)) { return names; } } } // build names array names = new String[7]; names[0] = id; for (int i = 1; i <= 6; i ++) { names[i] = pool.getLocalizedObject(TimeZoneNameGetter.INSTANCE, locale, i<5 ? (i<3 ? "std" : "dst") : "generic", i%2, id); } if (Objects.isNull(perLocale)) { perLocale = new ConcurrentHashMap<>(); } perLocale.put(locale, names); ref = new SoftReference<>(perLocale); cachedDisplayNames.put(id, ref); return names; }
Obtains a localized time zone strings from a TimeZoneNameProvider implementation.
/** * Obtains a localized time zone strings from a TimeZoneNameProvider * implementation. */
private static class TimeZoneNameGetter implements LocaleServiceProviderPool.LocalizedObjectGetter<TimeZoneNameProvider, String> { private static final TimeZoneNameGetter INSTANCE = new TimeZoneNameGetter(); @Override public String getObject(TimeZoneNameProvider timeZoneNameProvider, Locale locale, String requestID, Object... params) { assert params.length == 2; int style = (int) params[0]; String tzid = (String) params[1]; String value = getName(timeZoneNameProvider, locale, requestID, style, tzid); if (value == null) { Map<String, String> aliases = ZoneInfo.getAliasTable(); if (aliases != null) { String canonicalID = aliases.get(tzid); if (canonicalID != null) { value = getName(timeZoneNameProvider, locale, requestID, style, canonicalID); } if (value == null) { value = examineAliases(timeZoneNameProvider, locale, requestID, canonicalID != null ? canonicalID : tzid, style, aliases); } } } return value; } private static String examineAliases(TimeZoneNameProvider tznp, Locale locale, String requestID, String tzid, int style, Map<String, String> aliases) { for (Map.Entry<String, String> entry : aliases.entrySet()) { if (entry.getValue().equals(tzid)) { String alias = entry.getKey(); String name = getName(tznp, locale, requestID, style, alias); if (name != null) { return name; } name = examineAliases(tznp, locale, requestID, alias, style, aliases); if (name != null) { return name; } } } return null; } private static String getName(TimeZoneNameProvider timeZoneNameProvider, Locale locale, String requestID, int style, String tzid) { String value = null; switch (requestID) { case "std": value = timeZoneNameProvider.getDisplayName(tzid, false, style, locale); break; case "dst": value = timeZoneNameProvider.getDisplayName(tzid, true, style, locale); break; case "generic": value = timeZoneNameProvider.getGenericDisplayName(tzid, style, locale); break; } return value; } } // No instantiation private TimeZoneNameUtility() { } }