icuSources/i18n/unicode/tznames.h

   1 /*
   2 *******************************************************************************
   3 * Copyright (C) 2011-2013, 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 #ifndef U_HIDE_DRAFT_API
  18
  19 #include "unicode/uloc.h"
  20 #include "unicode/unistr.h"
  21
  22 U_CDECL_BEGIN
  23
  24 /**
  25  * Constants for time zone display name types.
  26  * @draft ICU 50
  27  */
  28 typedef enum UTimeZoneNameType {
  29     /**
  30      * Unknown display name type.
  31      * @draft ICU 50
  32      */
  33     UTZNM_UNKNOWN           = 0x00,
  34     /**
  35      * Long display name, such as "Eastern Time".
  36      * @draft ICU 50
  37      */
  38     UTZNM_LONG_GENERIC      = 0x01,
  39     /**
  40      * Long display name for standard time, such as "Eastern Standard Time".
  41      * @draft ICU 50
  42      */
  43     UTZNM_LONG_STANDARD     = 0x02,
  44     /**
  45      * Long display name for daylight saving time, such as "Eastern Daylight Time".
  46      * @draft ICU 50
  47      */
  48     UTZNM_LONG_DAYLIGHT     = 0x04,
  49     /**
  50      * Short display name, such as "ET".
  51      * @draft ICU 50
  52      */
  53     UTZNM_SHORT_GENERIC     = 0x08,
  54     /**
  55      * Short display name for standard time, such as "EST".
  56      * @draft ICU 50
  57      */
  58     UTZNM_SHORT_STANDARD    = 0x10,
  59     /**
  60      * Short display name for daylight saving time, such as "EDT".
  61      * @draft ICU 50
  62      */
  63     UTZNM_SHORT_DAYLIGHT    = 0x20,
  64 #ifndef U_HIDE_DRAFT_API
  65     /**
  66      * Exemplar location name, such as "Los Angeles".
  67      * @draft ICU 51
  68      */
  69     UTZNM_EXEMPLAR_LOCATION = 0x40
  70 #endif /* U_HIDE_DRAFT_API */
  71 } UTimeZoneNameType;
  72
  73 U_CDECL_END
  74
  75 U_NAMESPACE_BEGIN
  76
  77 class UVector;
  78 struct MatchInfo;
  79
  80 /**
  81  * <code>TimeZoneNames</code> is an abstract class representing the time zone display name data model defined
  82  * by <a href="http://www.unicode.org/reports/tr35/">UTS#35 Unicode Locale Data Markup Language (LDML)</a>.
  83  * The model defines meta zone, which is used for storing a set of display names. A meta zone can be shared
  84  * by multiple time zones. Also a time zone may have multiple meta zone historic mappings.
  85  * <p>
  86  * For example, people in the United States refer the zone used by the east part of North America as "Eastern Time".
  87  * The tz database contains multiple time zones "America/New_York", "America/Detroit", "America/Montreal" and some
  88  * others that belong to "Eastern Time". However, assigning different display names to these time zones does not make
  89  * much sense for most of people.
  90  * <p>
  91  * In <a href="http://cldr.unicode.org/">CLDR</a> (which uses LDML for representing locale data), the display name
  92  * "Eastern Time" is stored as long generic display name of a meta zone identified by the ID "America_Eastern".
  93  * Then, there is another table maintaining the historic mapping to meta zones for each time zone. The time zones in
  94  * the above example ("America/New_York", "America/Detroit"...) are mapped to the meta zone "America_Eastern".
  95  * <p>
  96  * Sometimes, a time zone is mapped to a different time zone in the past. For example, "America/Indiana/Knox"
  97  * had been moving "Eastern Time" and "Central Time" back and forth. Therefore, it is necessary that time zone
  98  * to meta zones mapping data are stored by date range.
  99  *
 100  * <p><b>Note:</b>
 101  * The methods in this class assume that time zone IDs are already canonicalized. For example, you may not get proper
 102  * result returned by a method with time zone ID "America/Indiana/Indianapolis", because it's not a canonical time zone
 103  * ID (the canonical time zone ID for the time zone is "America/Indianapolis". See
 104  * {@link TimeZone#getCanonicalID(const UnicodeString& id, UnicodeString& canonicalID, UErrorCode& status)} about ICU
 105  * canonical time zone IDs.
 106  *
 107  * <p>
 108  * In CLDR, most of time zone display names except location names are provided through meta zones. But a time zone may
 109  * have a specific name that is not shared with other time zones.
 110  *
 111  * For example, time zone "Europe/London" has English long name for standard time "Greenwich Mean Time", which is also
 112  * shared with other time zones. However, the long name for daylight saving time is "British Summer Time", which is only
 113  * used for "Europe/London".
 114  *
 115  * <p>
 116  * {@link #getTimeZoneDisplayName} is designed for accessing a name only used by a single time zone.
 117  * But is not necessarily mean that a subclass implementation use the same model with CLDR. A subclass implementation
 118  * may provide time zone names only through {@link #getTimeZoneDisplayName}, or only through {@link #getMetaZoneDisplayName},
 119  * or both.
 120  *
 121  * <p>
 122  * The default <code>TimeZoneNames</code> implementation returned by {@link #createInstance}
 123  * uses the locale data imported from CLDR. In CLDR, set of meta zone IDs and mappings between zone IDs and meta zone
 124  * IDs are shared by all locales. Therefore, the behavior of {@link #getAvailableMetaZoneIDs},
 125  * {@link #getMetaZoneID}, and {@link #getReferenceZoneID} won't be changed no matter
 126  * what locale is used for getting an instance of <code>TimeZoneNames</code>.
 127  *
 128  * @draft ICU 50
 129  */
 130 class U_I18N_API TimeZoneNames : public UObject {
 131 public:
 132     /**
 133      * Destructor.
 134      * @draft ICU 50
 135      */
 136     virtual ~TimeZoneNames();
 137
 138     /**
 139      * Return true if the given TimeZoneNames objects are emantically equal.
 140      * @param other the object to be compared with.
 141      * @return Return TRUE if the given Format objects are semantically equal.
 142      * @draft ICU 50
 143      */
 144     virtual UBool operator==(const TimeZoneNames& other) const = 0;
 145
 146     /**
 147      * Return true if the given TimeZoneNames objects are not semantically
 148      * equal.
 149      * @param other the object to be compared with.
 150      * @return Return TRUE if the given Format objects are not semantically equal.
 151      * @draft ICU 50
 152      */
 153     UBool operator!=(const TimeZoneNames& other) const { return !operator==(other); }
 154
 155     /**
 156      * Clone this object polymorphically.  The caller is responsible
 157      * for deleting the result when done.
 158      * @return A copy of the object
 159      * @draft ICU 50
 160      */
 161     virtual TimeZoneNames* clone() const = 0;
 162
 163     /**
 164      * Returns an instance of <code>TimeZoneDisplayNames</code> for the specified locale.
 165      *
 166      * @param locale The locale.
 167      * @param status Recevies the status.
 168      * @return An instance of <code>TimeZoneDisplayNames</code>
 169      * @draft ICU 50
 170      */
 171     static TimeZoneNames* U_EXPORT2 createInstance(const Locale& locale, UErrorCode& status);
 172
 173     /**
 174      * Returns an enumeration of all available meta zone IDs.
 175      * @param status Recevies the status.
 176      * @return an enumeration object, owned by the caller.
 177      * @draft ICU 50
 178      */
 179     virtual StringEnumeration* getAvailableMetaZoneIDs(UErrorCode& status) const = 0;
 180
 181     /**
 182      * Returns an enumeration of all available meta zone IDs used by the given time zone.
 183      * @param tzID The canoical tiem zone ID.
 184      * @param status Recevies the status.
 185      * @return an enumeration object, owned by the caller.
 186      * @draft ICU 50
 187      */
 188     virtual StringEnumeration* getAvailableMetaZoneIDs(const UnicodeString& tzID, UErrorCode& status) const = 0;
 189
 190     /**
 191      * Returns the meta zone ID for the given canonical time zone ID at the given date.
 192      * @param tzID The canonical time zone ID.
 193      * @param date The date.
 194      * @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
 195      *          corresponding meta zone at the given date or the implementation does not support meta zones, "bogus" state
 196      *          is set.
 197      * @return A reference to the result.
 198      * @draft ICU 50
 199      */
 200     virtual UnicodeString& getMetaZoneID(const UnicodeString& tzID, UDate date, UnicodeString& mzID) const = 0;
 201
 202     /**
 203      * Returns the reference zone ID for the given meta zone ID for the region.
 204      *
 205      * Note: Each meta zone must have a reference zone associated with a special region "001" (world).
 206      * Some meta zones may have region specific reference zone IDs other than the special region
 207      * "001". When a meta zone does not have any region specific reference zone IDs, this method
 208      * return the reference zone ID for the special region "001" (world).
 209      *
 210      * @param mzID The meta zone ID.
 211      * @param region The region.
 212      * @param tzID Receives the reference zone ID ("golden zone" in the LDML specification) for the given time zone ID for the
 213      *          region. If the meta zone is unknown or the implementation does not support meta zones, "bogus" state
 214      *          is set.
 215      * @return A reference to the result.
 216      * @draft ICU 50
 217      */
 218     virtual UnicodeString& getReferenceZoneID(const UnicodeString& mzID, const char* region, UnicodeString& tzID) const = 0;
 219
 220     /**
 221      * Returns the display name of the meta zone.
 222      * @param mzID The meta zone ID.
 223      * @param type The display name type. See {@link #UTimeZoneNameType}.
 224      * @param name Receives the display name of the meta zone. When this object does not have a localized display name for the given
 225      *         meta zone with the specified type or the implementation does not provide any display names associated
 226      *         with meta zones, "bogus" state is set.
 227      * @return A reference to the result.
 228      * @draft ICU 50
 229      */
 230     virtual UnicodeString& getMetaZoneDisplayName(const UnicodeString& mzID, UTimeZoneNameType type, UnicodeString& name) const = 0;
 231
 232     /**
 233      * Returns the display name of the time zone. Unlike {@link #getDisplayName},
 234      * this method does not get a name from a meta zone used by the time zone.
 235      * @param tzID The canonical time zone ID.
 236      * @param type The display name type. See {@link #UTimeZoneNameType}.
 237      * @param name Receives the display name for the time zone. When this object does not have a localized display name for the given
 238      *         time zone with the specified type, "bogus" state is set.
 239      * @return A reference to the result.
 240      * @draft ICU 50
 241      */
 242     virtual UnicodeString& getTimeZoneDisplayName(const UnicodeString& tzID, UTimeZoneNameType type, UnicodeString& name) const = 0;
 243
 244     /**
 245      * Returns the exemplar location name for the given time zone. When this object does not have a localized location
 246      * name, the default implementation may still returns a programmatically generated name with the logic described
 247      * below.
 248      * <ol>
 249      * <li>Check if the ID contains "/". If not, return null.
 250      * <li>Check if the ID does not start with "Etc/" or "SystemV/". If it does, return null.
 251      * <li>Extract a substring after the last occurrence of "/".
 252      * <li>Replace "_" with " ".
 253      * </ol>
 254      * For example, "New York" is returned for the time zone ID "America/New_York" when this object does not have the
 255      * localized location name.
 256      *
 257      * @param tzID The canonical time zone ID
 258      * @param name Receives the exemplar location name for the given time zone, or "bogus" state is set when a localized
 259      *          location name is not available and the fallback logic described above cannot extract location from the ID.
 260      * @return A reference to the result.
 261      * @draft ICU 50
 262      */
 263     virtual UnicodeString& getExemplarLocationName(const UnicodeString& tzID, UnicodeString& name) const;
 264
 265     /**
 266      * Returns the display name of the time zone at the given date.
 267      * <p>
 268      * <b>Note:</b> This method calls the subclass's {@link #getTimeZoneDisplayName} first. When the
 269      * result is bogus, this method calls {@link #getMetaZoneID} to get the meta zone ID mapped from the
 270      * time zone, then calls {@link #getMetaZoneDisplayName}.
 271      *
 272      * @param tzID The canonical time zone ID.
 273      * @param type The display name type. See {@link #UTimeZoneNameType}.
 274      * @param date The date.
 275      * @param name Receives the display name for the time zone at the given date. When this object does not have a localized display
 276      *          name for the time zone with the specified type and date, "bogus" state is set.
 277      * @return A reference to the result.
 278      * @draft ICU 50
 279      */
 280     virtual UnicodeString& getDisplayName(const UnicodeString& tzID, UTimeZoneNameType type, UDate date, UnicodeString& name) const;
 281
 282     /**
 283      * <code>MatchInfoCollection</code> represents a collection of time zone name matches used by
 284      * {@link TimeZoneNames#find}.
 285      * @internal
 286      */
 287     class U_I18N_API MatchInfoCollection : public UMemory {
 288     public:
 289         /**
 290          * Constructor.
 291          * @internal
 292          */
 293         MatchInfoCollection();
 294         /**
 295          * Destructor.
 296          * @internal
 297          */
 298         virtual ~MatchInfoCollection();
 299
 300 #ifndef U_HIDE_INTERNAL_API
 301         /**
 302          * Adds a zone match.
 303          * @param nameType The name type.
 304          * @param matchLength The match length.
 305          * @param tzID The time zone ID.
 306          * @param status Receives the status
 307          * @internal
 308          */
 309         void addZone(UTimeZoneNameType nameType, int32_t matchLength,
 310             const UnicodeString& tzID, UErrorCode& status);
 311
 312         /**
 313          * Adds a meata zone match.
 314          * @param nameType The name type.
 315          * @param matchLength The match length.
 316          * @param mzID The metazone ID.
 317          * @param status Receives the status
 318          * @internal
 319          */
 320         void addMetaZone(UTimeZoneNameType nameType, int32_t matchLength,
 321             const UnicodeString& mzID, UErrorCode& status);
 322
 323         /**
 324          * Returns the number of entries available in this object.
 325          * @return The number of entries.
 326          * @internal
 327          */
 328         int32_t size() const;
 329
 330         /**
 331          * Returns the time zone name type of a match at the specified index.
 332          * @param idx The index
 333          * @return The time zone name type. If the specified idx is out of range,
 334          *      it returns UTZNM_UNKNOWN.
 335          * @see UTimeZoneNameType
 336          * @internal
 337          */
 338         UTimeZoneNameType getNameTypeAt(int32_t idx) const;
 339
 340         /**
 341          * Returns the match length of a match at the specified index.
 342          * @param idx The index
 343          * @return The match length. If the specified idx is out of range,
 344          *      it returns 0.
 345          * @internal
 346          */
 347         int32_t getMatchLengthAt(int32_t idx) const;
 348
 349         /**
 350          * Gets the zone ID of a match at the specified index.
 351          * @param idx The index
 352          * @param tzID Receives the zone ID.
 353          * @return TRUE if the zone ID was set to tzID.
 354          * @internal
 355          */
 356         UBool getTimeZoneIDAt(int32_t idx, UnicodeString& tzID) const;
 357
 358         /**
 359          * Gets the metazone ID of a match at the specified index.
 360          * @param idx The index
 361          * @param mzID Receives the metazone ID
 362          * @return TRUE if the meta zone ID was set to mzID.
 363          * @internal
 364          */
 365         UBool getMetaZoneIDAt(int32_t idx, UnicodeString& mzID) const;
 366 #endif  /* U_HIDE_INTERNAL_API */
 367
 368     private:
 369         UVector* fMatches;  // vector of MatchEntry
 370
 371         UVector* matches(UErrorCode& status);
 372     };
 373
 374     /**
 375      * Finds time zone name prefix matches for the input text at the
 376      * given offset and returns a collection of the matches.
 377      * @param text The text.
 378      * @param start The starting offset within the text.
 379      * @param types The set of name types represented by bitwise flags of UTimeZoneNameType enums,
 380      *              or UTZNM_UNKNOWN for all name types.
 381      * @param status Receives the status.
 382      * @return A collection of matches (owned by the caller), or NULL if no matches are found.
 383      * @see UTimeZoneNameType
 384      * @see MatchInfoCollection
 385      * @internal
 386      */
 387     virtual MatchInfoCollection* find(const UnicodeString& text, int32_t start, uint32_t types, UErrorCode& status) const = 0;
 388 };
 389
 390 U_NAMESPACE_END
 391
 392 #endif /* U_HIDE_DRAFT_API */
 393 #endif
 394 #endif