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      1 /*
      2 *******************************************************************************
      3 * Copyright (C) 2011-2014, International Business Machines Corporation and
      4 * others. All Rights Reserved.
      5 *******************************************************************************
      6 */
      7 #ifndef __TZNAMES_H
      8 #define __TZNAMES_H
      9 
     10 /**
     11  * \file
     12  * \brief C++ API: TimeZoneNames
     13  */
     14 #include "unicode/utypes.h"
     15 
     16 #if !UCONFIG_NO_FORMATTING
     17 
     18 #include "unicode/uloc.h"
     19 #include "unicode/unistr.h"
     20 
     21 U_CDECL_BEGIN
     22 
     23 /**
     24  * Constants for time zone display name types.
     25  * @stable ICU 50
     26  */
     27 typedef enum UTimeZoneNameType {
     28     /**
     29      * Unknown display name type.
     30      * @stable ICU 50
     31      */
     32     UTZNM_UNKNOWN           = 0x00,
     33     /**
     34      * Long display name, such as "Eastern Time".
     35      * @stable ICU 50
     36      */
     37     UTZNM_LONG_GENERIC      = 0x01,
     38     /**
     39      * Long display name for standard time, such as "Eastern Standard Time".
     40      * @stable ICU 50
     41      */
     42     UTZNM_LONG_STANDARD     = 0x02,
     43     /**
     44      * Long display name for daylight saving time, such as "Eastern Daylight Time".
     45      * @stable ICU 50
     46      */
     47     UTZNM_LONG_DAYLIGHT     = 0x04,
     48     /**
     49      * Short display name, such as "ET".
     50      * @stable ICU 50
     51      */
     52     UTZNM_SHORT_GENERIC     = 0x08,
     53     /**
     54      * Short display name for standard time, such as "EST".
     55      * @stable ICU 50
     56      */
     57     UTZNM_SHORT_STANDARD    = 0x10,
     58     /**
     59      * Short display name for daylight saving time, such as "EDT".
     60      * @stable ICU 50
     61      */
     62     UTZNM_SHORT_DAYLIGHT    = 0x20,
     63     /**
     64      * Exemplar location name, such as "Los Angeles".
     65      * @stable ICU 51
     66      */
     67     UTZNM_EXEMPLAR_LOCATION = 0x40
     68 } UTimeZoneNameType;
     69 
     70 U_CDECL_END
     71 
     72 U_NAMESPACE_BEGIN
     73 
     74 class UVector;
     75 struct MatchInfo;
     76 
     77 /**
     78  * <code>TimeZoneNames</code> is an abstract class representing the time zone display name data model defined
     79  * by <a href="http://www.unicode.org/reports/tr35/">UTS#35 Unicode Locale Data Markup Language (LDML)</a>.
     80  * The model defines meta zone, which is used for storing a set of display names. A meta zone can be shared
     81  * by multiple time zones. Also a time zone may have multiple meta zone historic mappings.
     82  * <p>
     83  * For example, people in the United States refer the zone used by the east part of North America as "Eastern Time".
     84  * The tz database contains multiple time zones "America/New_York", "America/Detroit", "America/Montreal" and some
     85  * others that belong to "Eastern Time". However, assigning different display names to these time zones does not make
     86  * much sense for most of people.
     87  * <p>
     88  * In <a href="http://cldr.unicode.org/">CLDR</a> (which uses LDML for representing locale data), the display name
     89  * "Eastern Time" is stored as long generic display name of a meta zone identified by the ID "America_Eastern".
     90  * Then, there is another table maintaining the historic mapping to meta zones for each time zone. The time zones in
     91  * the above example ("America/New_York", "America/Detroit"...) are mapped to the meta zone "America_Eastern".
     92  * <p>
     93  * Sometimes, a time zone is mapped to a different time zone in the past. For example, "America/Indiana/Knox"
     94  * had been moving "Eastern Time" and "Central Time" back and forth. Therefore, it is necessary that time zone
     95  * to meta zones mapping data are stored by date range.
     96  *
     97  * <p><b>Note:</b>
     98  * The methods in this class assume that time zone IDs are already canonicalized. For example, you may not get proper
     99  * result returned by a method with time zone ID "America/Indiana/Indianapolis", because it's not a canonical time zone
    100  * ID (the canonical time zone ID for the time zone is "America/Indianapolis". See
    101  * {@link TimeZone#getCanonicalID(const UnicodeString& id, UnicodeString& canonicalID, UErrorCode& status)} about ICU
    102  * canonical time zone IDs.
    103  *
    104  * <p>
    105  * In CLDR, most of time zone display names except location names are provided through meta zones. But a time zone may
    106  * have a specific name that is not shared with other time zones.
    107  *
    108  * For example, time zone "Europe/London" has English long name for standard time "Greenwich Mean Time", which is also
    109  * shared with other time zones. However, the long name for daylight saving time is "British Summer Time", which is only
    110  * used for "Europe/London".
    111  *
    112  * <p>
    113  * {@link #getTimeZoneDisplayName} is designed for accessing a name only used by a single time zone.
    114  * But is not necessarily mean that a subclass implementation use the same model with CLDR. A subclass implementation
    115  * may provide time zone names only through {@link #getTimeZoneDisplayName}, or only through {@link #getMetaZoneDisplayName},
    116  * or both.
    117  *
    118  * <p>
    119  * The default <code>TimeZoneNames</code> implementation returned by {@link #createInstance}
    120  * uses the locale data imported from CLDR. In CLDR, set of meta zone IDs and mappings between zone IDs and meta zone
    121  * IDs are shared by all locales. Therefore, the behavior of {@link #getAvailableMetaZoneIDs},
    122  * {@link #getMetaZoneID}, and {@link #getReferenceZoneID} won't be changed no matter
    123  * what locale is used for getting an instance of <code>TimeZoneNames</code>.
    124  *
    125  * @stable ICU 50
    126  */
    127 class U_I18N_API TimeZoneNames : public UObject {
    128 public:
    129     /**
    130      * Destructor.
    131      * @stable ICU 50
    132      */
    133     virtual ~TimeZoneNames();
    134 
    135     /**
    136      * Return true if the given TimeZoneNames objects are emantically equal.
    137      * @param other the object to be compared with.
    138      * @return Return TRUE if the given Format objects are semantically equal.
    139      * @stable ICU 50
    140      */
    141     virtual UBool operator==(const TimeZoneNames& other) const = 0;
    142 
    143     /**
    144      * Return true if the given TimeZoneNames objects are not semantically
    145      * equal.
    146      * @param other the object to be compared with.
    147      * @return Return TRUE if the given Format objects are not semantically equal.
    148      * @stable ICU 50
    149      */
    150     UBool operator!=(const TimeZoneNames& other) const { return !operator==(other); }
    151 
    152     /**
    153      * Clone this object polymorphically.  The caller is responsible
    154      * for deleting the result when done.
    155      * @return A copy of the object
    156      * @stable ICU 50
    157      */
    158     virtual TimeZoneNames* clone() const = 0;
    159 
    160     /**
    161      * Returns an instance of <code>TimeZoneNames</code> for the specified locale.
    162      *
    163      * @param locale The locale.
    164      * @param status Receives the status.
    165      * @return An instance of <code>TimeZoneNames</code>
    166      * @stable ICU 50
    167      */
    168     static TimeZoneNames* U_EXPORT2 createInstance(const Locale& locale, UErrorCode& status);
    169 
    170 #ifndef U_HIDE_DRAFT_API
    171     /**
    172      * Returns an instance of <code>TimeZoneNames</code> containing only short specific
    173      * zone names (SHORT_STANDARD and SHORT_DAYLIGHT),
    174      * compatible with the IANA tz database's zone abbreviations (not localized).
    175      * <br>
    176      * Note: The input locale is used for resolving ambiguous names (e.g. "IST" is parsed
    177      * as Israel Standard Time for Israel, while it is parsed as India Standard Time for
    178      * all other regions). The zone names returned by this instance are not localized.
    179      * @draft ICU 54
    180      */
    181      static TimeZoneNames* U_EXPORT2 createTZDBInstance(const Locale& locale, UErrorCode& status);
    182 #endif /* U_HIDE_DRAFT_API */
    183 
    184     /**
    185      * Returns an enumeration of all available meta zone IDs.
    186      * @param status Receives the status.
    187      * @return an enumeration object, owned by the caller.
    188      * @stable ICU 50
    189      */
    190     virtual StringEnumeration* getAvailableMetaZoneIDs(UErrorCode& status) const = 0;
    191 
    192     /**
    193      * Returns an enumeration of all available meta zone IDs used by the given time zone.
    194      * @param tzID The canoical tiem zone ID.
    195      * @param status Receives the status.
    196      * @return an enumeration object, owned by the caller.
    197      * @stable ICU 50
    198      */
    199     virtual StringEnumeration* getAvailableMetaZoneIDs(const UnicodeString& tzID, UErrorCode& status) const = 0;
    200 
    201     /**
    202      * Returns the meta zone ID for the given canonical time zone ID at the given date.
    203      * @param tzID The canonical time zone ID.
    204      * @param date The date.
    205      * @param mzID Receives the meta zone ID for the given time zone ID at the given date. If the time zone does not have a
    206      *          corresponding meta zone at the given date or the implementation does not support meta zones, "bogus" state
    207      *          is set.
    208      * @return A reference to the result.
    209      * @stable ICU 50
    210      */
    211     virtual UnicodeString& getMetaZoneID(const UnicodeString& tzID, UDate date, UnicodeString& mzID) const = 0;
    212 
    213     /**
    214      * Returns the reference zone ID for the given meta zone ID for the region.
    215      *
    216      * Note: Each meta zone must have a reference zone associated with a special region "001" (world).
    217      * Some meta zones may have region specific reference zone IDs other than the special region
    218      * "001". When a meta zone does not have any region specific reference zone IDs, this method
    219      * return the reference zone ID for the special region "001" (world).
    220      *
    221      * @param mzID The meta zone ID.
    222      * @param region The region.
    223      * @param tzID Receives the reference zone ID ("golden zone" in the LDML specification) for the given time zone ID for the
    224      *          region. If the meta zone is unknown or the implementation does not support meta zones, "bogus" state
    225      *          is set.
    226      * @return A reference to the result.
    227      * @stable ICU 50
    228      */
    229     virtual UnicodeString& getReferenceZoneID(const UnicodeString& mzID, const char* region, UnicodeString& tzID) const = 0;
    230 
    231     /**
    232      * Returns the display name of the meta zone.
    233      * @param mzID The meta zone ID.
    234      * @param type The display name type. See {@link #UTimeZoneNameType}.
    235      * @param name Receives the display name of the meta zone. When this object does not have a localized display name for the given
    236      *         meta zone with the specified type or the implementation does not provide any display names associated
    237      *         with meta zones, "bogus" state is set.
    238      * @return A reference to the result.
    239      * @stable ICU 50
    240      */
    241     virtual UnicodeString& getMetaZoneDisplayName(const UnicodeString& mzID, UTimeZoneNameType type, UnicodeString& name) const = 0;
    242 
    243     /**
    244      * Returns the display name of the time zone. Unlike {@link #getDisplayName},
    245      * this method does not get a name from a meta zone used by the time zone.
    246      * @param tzID The canonical time zone ID.
    247      * @param type The display name type. See {@link #UTimeZoneNameType}.
    248      * @param name Receives the display name for the time zone. When this object does not have a localized display name for the given
    249      *         time zone with the specified type, "bogus" state is set.
    250      * @return A reference to the result.
    251      * @stable ICU 50
    252      */
    253     virtual UnicodeString& getTimeZoneDisplayName(const UnicodeString& tzID, UTimeZoneNameType type, UnicodeString& name) const = 0;
    254 
    255     /**
    256      * Returns the exemplar location name for the given time zone. When this object does not have a localized location
    257      * name, the default implementation may still returns a programmatically generated name with the logic described
    258      * below.
    259      * <ol>
    260      * <li>Check if the ID contains "/". If not, return null.
    261      * <li>Check if the ID does not start with "Etc/" or "SystemV/". If it does, return null.
    262      * <li>Extract a substring after the last occurrence of "/".
    263      * <li>Replace "_" with " ".
    264      * </ol>
    265      * For example, "New York" is returned for the time zone ID "America/New_York" when this object does not have the
    266      * localized location name.
    267      *
    268      * @param tzID The canonical time zone ID
    269      * @param name Receives the exemplar location name for the given time zone, or "bogus" state is set when a localized
    270      *          location name is not available and the fallback logic described above cannot extract location from the ID.
    271      * @return A reference to the result.
    272      * @stable ICU 50
    273      */
    274     virtual UnicodeString& getExemplarLocationName(const UnicodeString& tzID, UnicodeString& name) const;
    275 
    276     /**
    277      * Returns the display name of the time zone at the given date.
    278      * <p>
    279      * <b>Note:</b> This method calls the subclass's {@link #getTimeZoneDisplayName} first. When the
    280      * result is bogus, this method calls {@link #getMetaZoneID} to get the meta zone ID mapped from the
    281      * time zone, then calls {@link #getMetaZoneDisplayName}.
    282      *
    283      * @param tzID The canonical time zone ID.
    284      * @param type The display name type. See {@link #UTimeZoneNameType}.
    285      * @param date The date.
    286      * @param name Receives the display name for the time zone at the given date. When this object does not have a localized display
    287      *          name for the time zone with the specified type and date, "bogus" state is set.
    288      * @return A reference to the result.
    289      * @stable ICU 50
    290      */
    291     virtual UnicodeString& getDisplayName(const UnicodeString& tzID, UTimeZoneNameType type, UDate date, UnicodeString& name) const;
    292 
    293     /**
    294      * <code>MatchInfoCollection</code> represents a collection of time zone name matches used by
    295      * {@link TimeZoneNames#find}.
    296      * @internal
    297      */
    298     class U_I18N_API MatchInfoCollection : public UMemory {
    299     public:
    300         /**
    301          * Constructor.
    302          * @internal
    303          */
    304         MatchInfoCollection();
    305         /**
    306          * Destructor.
    307          * @internal
    308          */
    309         virtual ~MatchInfoCollection();
    310 
    311 #ifndef U_HIDE_INTERNAL_API
    312         /**
    313          * Adds a zone match.
    314          * @param nameType The name type.
    315          * @param matchLength The match length.
    316          * @param tzID The time zone ID.
    317          * @param status Receives the status
    318          * @internal
    319          */
    320         void addZone(UTimeZoneNameType nameType, int32_t matchLength,
    321             const UnicodeString& tzID, UErrorCode& status);
    322 
    323         /**
    324          * Adds a meata zone match.
    325          * @param nameType The name type.
    326          * @param matchLength The match length.
    327          * @param mzID The metazone ID.
    328          * @param status Receives the status
    329          * @internal
    330          */
    331         void addMetaZone(UTimeZoneNameType nameType, int32_t matchLength,
    332             const UnicodeString& mzID, UErrorCode& status);
    333 
    334         /**
    335          * Returns the number of entries available in this object.
    336          * @return The number of entries.
    337          * @internal
    338          */
    339         int32_t size() const;
    340 
    341         /**
    342          * Returns the time zone name type of a match at the specified index.
    343          * @param idx The index
    344          * @return The time zone name type. If the specified idx is out of range,
    345          *      it returns UTZNM_UNKNOWN.
    346          * @see UTimeZoneNameType
    347          * @internal
    348          */
    349         UTimeZoneNameType getNameTypeAt(int32_t idx) const;
    350 
    351         /**
    352          * Returns the match length of a match at the specified index.
    353          * @param idx The index
    354          * @return The match length. If the specified idx is out of range,
    355          *      it returns 0.
    356          * @internal
    357          */
    358         int32_t getMatchLengthAt(int32_t idx) const;
    359 
    360         /**
    361          * Gets the zone ID of a match at the specified index.
    362          * @param idx The index
    363          * @param tzID Receives the zone ID.
    364          * @return TRUE if the zone ID was set to tzID.
    365          * @internal
    366          */
    367         UBool getTimeZoneIDAt(int32_t idx, UnicodeString& tzID) const;
    368 
    369         /**
    370          * Gets the metazone ID of a match at the specified index.
    371          * @param idx The index
    372          * @param mzID Receives the metazone ID
    373          * @return TRUE if the meta zone ID was set to mzID.
    374          * @internal
    375          */
    376         UBool getMetaZoneIDAt(int32_t idx, UnicodeString& mzID) const;
    377 #endif  /* U_HIDE_INTERNAL_API */
    378 
    379     private:
    380         UVector* fMatches;  // vector of MatchEntry
    381 
    382         UVector* matches(UErrorCode& status);
    383     };
    384 
    385     /**
    386      * Finds time zone name prefix matches for the input text at the
    387      * given offset and returns a collection of the matches.
    388      * @param text The text.
    389      * @param start The starting offset within the text.
    390      * @param types The set of name types represented by bitwise flags of UTimeZoneNameType enums,
    391      *              or UTZNM_UNKNOWN for all name types.
    392      * @param status Receives the status.
    393      * @return A collection of matches (owned by the caller), or NULL if no matches are found.
    394      * @see UTimeZoneNameType
    395      * @see MatchInfoCollection
    396      * @internal
    397      */
    398     virtual MatchInfoCollection* find(const UnicodeString& text, int32_t start, uint32_t types, UErrorCode& status) const = 0;
    399 };
    400 
    401 U_NAMESPACE_END
    402 
    403 #endif
    404 #endif
    405