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/*
 *******************************************************************************
 * Copyright (C) 2011, International Business Machines Corporation and         *
 * others. All Rights Reserved.                                                *
 *******************************************************************************
 */
package com.ibm.icu.text;

import java.io.Serializable;
import java.util.Collection;
import java.util.Collections;
import java.util.EnumSet;
import java.util.Set;
import java.util.regex.Pattern;

import com.ibm.icu.impl.ICUConfig;
import com.ibm.icu.impl.SoftCache;
import com.ibm.icu.util.TimeZone;
import com.ibm.icu.util.ULocale;

/**
 * TimeZoneNames is an abstract class representing the time zone display name data model defined
 * by UTS#35 Unicode Locale Data Markup Language (LDML).
 * The model defines meta zone, which is used for storing a set of display names. A meta zone can be shared
 * by multiple time zones. Also a time zone may have multiple meta zone historic mappings.
 * 

* For example, people in the United States refer the zone used by the east part of North America as "Eastern Time". * The tz database contains multiple time zones "America/New_York", "America/Detroit", "America/Montreal" and some * others that belong to "Eastern Time". However, assigning different display names to these time zones does not make * much sense for most of people. *

* In CLDR (which uses LDML for representing locale data), the display name * "Eastern Time" is stored as long generic display name of a meta zone identified by the ID "America_Eastern". * Then, there is another table maintaining the historic mapping to meta zones for each time zone. The time zones in * the above example ("America/New_York", "America/Detroit"...) are mapped to the meta zone "America_Eastern". *

* Sometimes, a time zone is mapped to a different time zone in the past. For example, "America/Indiana/Knox" * had been moving "Eastern Time" and "Central Time" back and forth. Therefore, it is necessary that time zone * to meta zones mapping data are stored by date range. * *

Note: *

* {@link TimeZoneFormat} assumes an instance of TimeZoneNames is immutable. If you want to provide * your own TimeZoneNames implementation and use it with {@link TimeZoneFormat}, you must follow * the contract. *

* The methods in this class assume that time zone IDs are already canonicalized. For example, you may not get proper * result returned by a method with time zone ID "America/Indiana/Indianapolis", because it's not a canonical time zone * ID (the canonical time zone ID for the time zone is "America/Indianapolis". See * {@link TimeZone#getCanonicalID(String)} about ICU canonical time zone IDs. * *

* In CLDR, most of time zone display names except location names are provided through meta zones. But a time zone may * have a specific name that is not shared with other time zones. * * For example, time zone "Europe/London" has English long name for standard time "Greenwich Mean Time", which is also * shared with other time zones. However, the long name for daylight saving time is "British Summer Time", which is only * used for "Europe/London". * *

* {@link #getTimeZoneDisplayName(String, NameType)} is designed for accessing a name only used by a single time zone. * But is not necessarily mean that a subclass implementation use the same model with CLDR. A subclass implementation * may provide time zone names only through {@link #getTimeZoneDisplayName(String, NameType)}, or only through * {@link #getMetaZoneDisplayName(String, NameType)}, or both. * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract class TimeZoneNames implements Serializable { private static final long serialVersionUID = -9180227029248969153L; /** * Time zone display name types * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public enum NameType { /** * Long display name, such as "Eastern Time". * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ LONG_GENERIC, /** * Long display name for standard time, such as "Eastern Standard Time". * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ LONG_STANDARD, /** * Long display name for daylight saving time, such as "Eastern Daylight Time". * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ LONG_DAYLIGHT, /** * Short display name, such as "ET". * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ SHORT_GENERIC, /** * Short display name for standard time, such as "EST". * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ SHORT_STANDARD, /** * Short display name for daylight saving time, such as "EDT". * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ SHORT_DAYLIGHT, } private static Cache TZNAMES_CACHE = new Cache(); private static final Factory TZNAMES_FACTORY; private static final String FACTORY_NAME_PROP = "com.ibm.icu.text.TimeZoneNames.Factory.impl"; private static final String DEFAULT_FACTORY_CLASS = "com.ibm.icu.impl.TimeZoneNamesFactoryImpl"; private static final Pattern LOC_EXCLUSION_PATTERN = Pattern.compile("Etc/.*|SystemV/.*|.*/Riyadh8[7-9]"); static { Factory factory = null; String classname = ICUConfig.get(FACTORY_NAME_PROP, DEFAULT_FACTORY_CLASS); while (true) { try { factory = (Factory) Class.forName(classname).newInstance(); break; } catch (ClassNotFoundException cnfe) { // fall through } catch (IllegalAccessException iae) { // fall through } catch (InstantiationException ie) { // fall through } if (classname.equals(DEFAULT_FACTORY_CLASS)) { break; } classname = DEFAULT_FACTORY_CLASS; } if (factory == null) { factory = new DefaultTimeZoneNames.FactoryImpl(); } TZNAMES_FACTORY = factory; } /** * Returns an instance of TimeZoneDisplayNames for the specified locale. * * @param locale * The locale. * @return An instance of TimeZoneDisplayNames * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public static TimeZoneNames getInstance(ULocale locale) { String key = locale.getBaseName(); return TZNAMES_CACHE.getInstance(key, locale); } /** * Returns an immutable set of all available meta zone IDs. * @return An immutable set of all available meta zone IDs. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract Set getAvailableMetaZoneIDs(); /** * Returns an immutable set of all available meta zone IDs used by the given time zone. * * @param tzID * The canonical time zone ID. * @return An immutable set of all available meta zone IDs used by the given time zone. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract Set getAvailableMetaZoneIDs(String tzID); /** * Returns the meta zone ID for the given canonical time zone ID at the given date. * * @param tzID * The canonical time zone ID. * @param date * The date. * @return The meta zone ID for the given time zone ID at the given date. If the time zone does not have a * corresponding meta zone at the given date or the implementation does not support meta zones, null is * returned. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract String getMetaZoneID(String tzID, long date); /** * Returns the reference zone ID for the given meta zone ID for the region. * * @param mzID * The meta zone ID. * @param region * The region. * @return The reference zone ID ("golden zone" in the LDML specification) for the given time zone ID for the * region. If the meta zone is unknown or the implementation does not support meta zones, null is returned. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract String getReferenceZoneID(String mzID, String region); /** * Returns the display name of the meta zone. * * @param mzID * The meta zone ID. * @param type * The display name type. See {@link TimeZoneNames.NameType}. * @return The display name of the meta zone. When this object does not have a localized display name for the given * meta zone with the specified type or the implementation does not provide any display names associated * with meta zones, null is returned. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract String getMetaZoneDisplayName(String mzID, NameType type); /** * Returns the display name of the time zone at the given date. * *

* Note: This method calls the subclass's {@link #getTimeZoneDisplayName(String, NameType)} first. When the * result is null, this method calls {@link #getMetaZoneID(String, long)} to get the meta zone ID mapped from the * time zone, then calls {@link #getMetaZoneDisplayName(String, NameType)}. * * @param tzID * The canonical time zone ID. * @param type * The display name type. See {@link TimeZoneNames.NameType}. * @param date * The date * @return The display name for the time zone at the given date. When this object does not have a localized display * name for the time zone with the specified type and date, null is returned. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public final String getDisplayName(String tzID, NameType type, long date) { String name = getTimeZoneDisplayName(tzID, type); if (name == null) { String mzID = getMetaZoneID(tzID, date); name = getMetaZoneDisplayName(mzID, type); } return name; } /** * Returns the display name of the time zone. Unlike {@link #getDisplayName(String, NameType, long)}, * this method does not get a name from a meta zone used by the time zone. * * @param tzID * The canonical time zone ID. * @param type * The display name type. See {@link TimeZoneNames.NameType}. * @return The display name for the time zone. When this object does not have a localized display name for the given * time zone with the specified type, null is returned. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public abstract String getTimeZoneDisplayName(String tzID, NameType type); /** * Returns the exemplar location name for the given time zone. When this object does not have a localized location * name, the default implementation may still returns a programmatically generated name with the logic described * below. *

    *
  1. Check if the ID contains "/". If not, return null. *
  2. Check if the ID does not start with "Etc/" or "SystemV/". If it does, return null. *
  3. Extract a substring after the last occurrence of "/". *
  4. Replace "_" with " ". *
* For example, "New York" is returned for the time zone ID "America/New_York" when this object does not have the * localized location name. * * @param tzID * The canonical time zone ID * @return The exemplar location name for the given time zone, or null when a localized location name is not * available and the fallback logic described above cannot extract location from the ID. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public String getExemplarLocationName(String tzID) { if (tzID == null || tzID.length() == 0 || LOC_EXCLUSION_PATTERN.matcher(tzID).matches()) { return null; } String location = null; int sep = tzID.lastIndexOf('/'); if (sep > 0 && sep + 1 < tzID.length()) { location = tzID.substring(sep + 1).replace('_', ' '); } return location; } /** * Finds time zone name prefix matches for the input text at the * given offset and returns a collection of the matches. * * @param text the text. * @param start the starting offset within the text. * @param types the set of name types, or null for all name types. * @return A collection of matches. * @see NameType * @see MatchInfo * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public Collection find(CharSequence text, int start, EnumSet types) { throw new UnsupportedOperationException("The method is not implemented in TimeZoneNames base class."); } /** * A MatchInfo represents a time zone name match used by * {@link TimeZoneNames#find(CharSequence, int, EnumSet)}. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public static class MatchInfo { private NameType _nameType; private String _tzID; private String _mzID; private int _matchLength; /** * Constructing a MatchInfo. * * @param nameType the name type enum. * @param tzID the time zone ID, or null * @param mzID the meta zone ID, or null * @param matchLength the match length. * @throws IllegalArgumentException when 1) nameType is null, * or 2) both tzID and mzID are null, * or 3) matchLength is 0 or smaller. * @see NameType * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public MatchInfo(NameType nameType, String tzID, String mzID, int matchLength) { if (nameType == null) { throw new IllegalArgumentException("nameType is null"); } if (tzID == null && mzID == null) { throw new IllegalArgumentException("Either tzID or mzID must be available"); } if (matchLength <= 0) { throw new IllegalArgumentException("matchLength must be positive value"); } _nameType = nameType; _tzID = tzID; _mzID = mzID; _matchLength = matchLength; } /** * Returns the time zone ID, or null if not available. * *

Note: A MatchInfo must have either a time zone ID * or a meta zone ID. * * @return the time zone ID, or null. * @see #mzID() * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public String tzID() { return _tzID; } /** * Returns the meta zone ID, or null if not available. * *

Note: A MatchInfo must have either a time zone ID * or a meta zone ID. * * @return the meta zone ID, or null. * @see #tzID() * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public String mzID() { return _mzID; } /** * Returns the time zone name type. * @return the time zone name type enum. * @see NameType * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public NameType nameType() { return _nameType; } /** * Returns the match length. * @return the match length. * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ public int matchLength() { return _matchLength; } } /** * Sole constructor for invocation by subclass constructors. * * @draft ICU 49 * @provisional This API might change or be removed in a future release. */ protected TimeZoneNames() { } /** * The super class of TimeZoneNames service factory classes. * * @internal */ public static abstract class Factory { /** * The factory method of TimeZoneNames. * * @param locale * The display locale * @return An instance of TimeZoneNames. * @internal */ public abstract TimeZoneNames getTimeZoneNames(ULocale locale); } /** * TimeZoneNames cache used by {@link TimeZoneNames#getInstance(ULocale)} */ private static class Cache extends SoftCache { /* * (non-Javadoc) * * @see com.ibm.icu.impl.CacheBase#createInstance(java.lang.Object, java.lang.Object) */ @Override protected TimeZoneNames createInstance(String key, ULocale data) { return TZNAMES_FACTORY.getTimeZoneNames(data); } } ///CLOVER:OFF /** * The default implementation of TimeZoneNames used by {@link TimeZoneNames#getInstance(ULocale)} when * the ICU4J tznamedata component is not available. */ private static class DefaultTimeZoneNames extends TimeZoneNames { private static final long serialVersionUID = -995672072494349071L; public static final DefaultTimeZoneNames INSTANCE = new DefaultTimeZoneNames(); /* (non-Javadoc) * @see com.ibm.icu.text.TimeZoneNames#getAvailableMetaZoneIDs() */ @Override public Set getAvailableMetaZoneIDs() { return Collections.emptySet(); } /* (non-Javadoc) * @see com.ibm.icu.text.TimeZoneNames#getAvailableMetaZoneIDs(java.lang.String) */ @Override public Set getAvailableMetaZoneIDs(String tzID) { return Collections.emptySet(); } /* * (non-Javadoc) * * @see com.ibm.icu.text.TimeZoneNames#getMetaZoneID (java.lang.String, long) */ @Override public String getMetaZoneID(String tzID, long date) { return null; } /* * (non-Javadoc) * * @see com.ibm.icu.text.TimeZoneNames#getReferenceZoneID(java.lang.String, java.lang.String) */ @Override public String getReferenceZoneID(String mzID, String region) { return null; } /* * (non-Javadoc) * @see com.ibm.icu.text.TimeZoneNames#getMetaZoneDisplayName(java.lang.String, com.ibm.icu.text.TimeZoneNames.NameType) */ @Override public String getMetaZoneDisplayName(String mzID, NameType type) { return null; } /* * (non-Javadoc) * @see com.ibm.icu.text.TimeZoneNames#getTimeZoneDisplayName(java.lang.String, com.ibm.icu.text.TimeZoneNames.NameType) */ @Override public String getTimeZoneDisplayName(String tzID, NameType type) { return null; } /* (non-Javadoc) * @see com.ibm.icu.text.TimeZoneNames#find(java.lang.CharSequence, int, com.ibm.icu.text.TimeZoneNames.NameType[]) */ @Override public Collection find(CharSequence text, int start, EnumSet nameTypes) { return Collections.emptyList(); } /** * The default TimeZoneNames factory called from {@link TimeZoneNames#getInstance(ULocale)} when * the ICU4J tznamedata component is not available. */ public static class FactoryImpl extends Factory { /* * (non-Javadoc) * * @see com.ibm.icu.text.TimeZoneNames.Factory#getTimeZoneNames (com.ibm.icu.util.ULocale) */ @Override public TimeZoneNames getTimeZoneNames(ULocale locale) { return DefaultTimeZoneNames.INSTANCE; } } } ///CLOVER:ON }





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