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1 /*
2 *******************************************************************************
3 * Copyright (C) 2011-2012, 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_INTERNAL_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 } UTimeZoneNameType;
65 
66 U_CDECL_END
67 
68 U_NAMESPACE_BEGIN
69 
70 class UVector;
71 struct MatchInfo;
72 
73 /**
74  * <code>TimeZoneNames</code> is an abstract class representing the time zone display name data model defined
75  * by <a href="http://www.unicode.org/reports/tr35/">UTS#35 Unicode Locale Data Markup Language (LDML)</a>.
76  * The model defines meta zone, which is used for storing a set of display names. A meta zone can be shared
77  * by multiple time zones. Also a time zone may have multiple meta zone historic mappings.
78  * <p>
79  * For example, people in the United States refer the zone used by the east part of North America as "Eastern Time".
80  * The tz database contains multiple time zones "America/New_York", "America/Detroit", "America/Montreal" and some
81  * others that belong to "Eastern Time". However, assigning different display names to these time zones does not make
82  * much sense for most of people.
83  * <p>
84  * In <a href="http://cldr.unicode.org/">CLDR</a> (which uses LDML for representing locale data), the display name
85  * "Eastern Time" is stored as long generic display name of a meta zone identified by the ID "America_Eastern".
86  * Then, there is another table maintaining the historic mapping to meta zones for each time zone. The time zones in
87  * the above example ("America/New_York", "America/Detroit"...) are mapped to the meta zone "America_Eastern".
88  * <p>
89  * Sometimes, a time zone is mapped to a different time zone in the past. For example, "America/Indiana/Knox"
90  * had been moving "Eastern Time" and "Central Time" back and forth. Therefore, it is necessary that time zone
91  * to meta zones mapping data are stored by date range.
92  *
93  * <p><b>Note:</b>
94  * The methods in this class assume that time zone IDs are already canonicalized. For example, you may not get proper
95  * result returned by a method with time zone ID "America/Indiana/Indianapolis", because it's not a canonical time zone
96  * ID (the canonical time zone ID for the time zone is "America/Indianapolis". See
97  * {@link TimeZone#getCanonicalID(const UnicodeString& id, UnicodeString& canonicalID, UErrorCode& status)} about ICU
98  * canonical time zone IDs.
99  *
100  * <p>
101  * In CLDR, most of time zone display names except location names are provided through meta zones. But a time zone may
102  * have a specific name that is not shared with other time zones.
103  *
104  * For example, time zone "Europe/London" has English long name for standard time "Greenwich Mean Time", which is also
105  * shared with other time zones. However, the long name for daylight saving time is "British Summer Time", which is only
106  * used for "Europe/London".
107  *
108  * <p>
109  * {@link #getTimeZoneDisplayName} is designed for accessing a name only used by a single time zone.
110  * But is not necessarily mean that a subclass implementation use the same model with CLDR. A subclass implementation
111  * may provide time zone names only through {@link #getTimeZoneDisplayName}, or only through {@link #getMetaZoneDisplayName},
112  * or both.
113  *
114  * @draft ICU 50
115  */
116 class U_I18N_API TimeZoneNames : public UObject {
117 public:
118     /**
119      * Destructor.
120      * @draft ICU 50
121      */
122     virtual ~TimeZoneNames();
123 
124     /**
125      * Return true if the given TimeZoneNames objects are emantically equal.
126      * @param other the object to be compared with.
127      * @return Return TRUE if the given Format objects are semantically equal.
128      * @draft ICU 50
129      */
130     virtual UBool operator==(const TimeZoneNames& other) const = 0;
131 
132     /**
133      * Return true if the given TimeZoneNames objects are not semantically
134      * equal.
135      * @param other the object to be compared with.
136      * @return Return TRUE if the given Format objects are not semantically equal.
137      * @draft ICU 50
138      */
139     UBool operator!=(const TimeZoneNames& other) const { return !operator==(other); }
140 
141     /**
142      * Clone this object polymorphically.  The caller is responsible
143      * for deleting the result when done.
144      * @return A copy of the object
145      * @draft ICU 50
146      */
147     virtual TimeZoneNames* clone() const = 0;
148 
149     /**
150      * Returns an instance of <code>TimeZoneDisplayNames</code> for the specified locale.
151      *
152      * @param locale The locale.
153      * @param status Recevies the status.
154      * @return An instance of <code>TimeZoneDisplayNames</code>
155      * @draft ICU 50
156      */
157     static TimeZoneNames* U_EXPORT2 createInstance(const Locale& locale, UErrorCode& status);
158 
159     /**
160      * Returns an enumeration of all available meta zone IDs.
161      * @param status Recevies the status.
162      * @return an enumeration object, owned by the caller.
163      * @draft ICU 50
164      */
165     virtual StringEnumeration* getAvailableMetaZoneIDs(UErrorCode& status) const = 0;
166 
167     /**
168      * Returns an enumeration of all available meta zone IDs used by the given time zone.
169      * @param tzID The canoical tiem zone ID.
170      * @param status Recevies the status.
171      * @return an enumeration object, owned by the caller.
172      * @draft ICU 50
173      */
174     virtual StringEnumeration* getAvailableMetaZoneIDs(const UnicodeString& tzID, UErrorCode& status) const = 0;
175 
176     /**
177      * Returns the meta zone ID for the given canonical time zone ID at the given date.
178      * @param tzID The canonical time zone ID.
179      * @param date The date.
180      * @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
181      *          corresponding meta zone at the given date or the implementation does not support meta zones, "bogus" state
182      *          is set.
183      * @return A reference to the result.
184      * @draft ICU 50
185      */
186     virtual UnicodeString& getMetaZoneID(const UnicodeString& tzID, UDate date, UnicodeString& mzID) const = 0;
187 
188     /**
189      * Returns the reference zone ID for the given meta zone ID for the region.
190      * @param mzID The meta zone ID.
191      * @param region The region.
192      * @param tzID Receives the reference zone ID ("golden zone" in the LDML specification) for the given time zone ID for the
193      *          region. If the meta zone is unknown or the implementation does not support meta zones, "bogus" state
194      *          is set.
195      * @return A reference to the result.
196      * @draft ICU 50
197      */
198     virtual UnicodeString& getReferenceZoneID(const UnicodeString& mzID, const char* region, UnicodeString& tzID) const = 0;
199 
200     /**
201      * Returns the display name of the meta zone.
202      * @param mzID The meta zone ID.
203      * @param type The display name type. See {@link #UTimeZoneNameType}.
204      * @param name Receives the display name of the meta zone. When this object does not have a localized display name for the given
205      *         meta zone with the specified type or the implementation does not provide any display names associated
206      *         with meta zones, "bogus" state is set.
207      * @return A reference to the result.
208      * @draft ICU 50
209      */
210     virtual UnicodeString& getMetaZoneDisplayName(const UnicodeString& mzID, UTimeZoneNameType type, UnicodeString& name) const = 0;
211 
212     /**
213      * Returns the display name of the time zone. Unlike {@link #getDisplayName},
214      * this method does not get a name from a meta zone used by the time zone.
215      * @param tzID The canonical time zone ID.
216      * @param type The display name type. See {@link #UTimeZoneNameType}.
217      * @param name Receives the display name for the time zone. When this object does not have a localized display name for the given
218      *         time zone with the specified type, "bogus" state is set.
219      * @return A reference to the result.
220      * @draft ICU 50
221      */
222     virtual UnicodeString& getTimeZoneDisplayName(const UnicodeString& tzID, UTimeZoneNameType type, UnicodeString& name) const = 0;
223 
224     /**
225      * Returns the exemplar location name for the given time zone. When this object does not have a localized location
226      * name, the default implementation may still returns a programmatically generated name with the logic described
227      * below.
228      * <ol>
229      * <li>Check if the ID contains "/". If not, return null.
230      * <li>Check if the ID does not start with "Etc/" or "SystemV/". If it does, return null.
231      * <li>Extract a substring after the last occurrence of "/".
232      * <li>Replace "_" with " ".
233      * </ol>
234      * For example, "New York" is returned for the time zone ID "America/New_York" when this object does not have the
235      * localized location name.
236      *
237      * @param tzID The canonical time zone ID
238      * @param name Receives the exemplar location name for the given time zone, or "bogus" state is set when a localized
239      *          location name is not available and the fallback logic described above cannot extract location from the ID.
240      * @return A reference to the result.
241      * @draft ICU 50
242      */
243     virtual UnicodeString& getExemplarLocationName(const UnicodeString& tzID, UnicodeString& name) const;
244 
245     /**
246      * Returns the display name of the time zone at the given date.
247      * <p>
248      * <b>Note:</b> This method calls the subclass's {@link #getTimeZoneDisplayName} first. When the
249      * result is bogus, this method calls {@link #getMetaZoneID} to get the meta zone ID mapped from the
250      * time zone, then calls {@link #getMetaZoneDisplayName}.
251      *
252      * @param tzID The canonical time zone ID.
253      * @param type The display name type. See {@link #UTimeZoneNameType}.
254      * @param date The date.
255      * @param name Receives the display name for the time zone at the given date. When this object does not have a localized display
256      *          name for the time zone with the specified type and date, "bogus" state is set.
257      * @return A reference to the result.
258      * @draft ICU 50
259      */
260     virtual UnicodeString& getDisplayName(const UnicodeString& tzID, UTimeZoneNameType type, UDate date, UnicodeString& name) const;
261 
262     /**
263      * <code>MatchInfoCollection</code> represents a collection of time zone name matches used by
264      * {@link TimeZoneNames#find}.
265      * @internal
266      */
267     class U_I18N_API MatchInfoCollection : public UMemory {
268     public:
269         /**
270          * Constructor.
271          * @internal
272          */
273         MatchInfoCollection();
274         /**
275          * Destructor.
276          * @internal
277          */
278         virtual ~MatchInfoCollection();
279 
280         /**
281          * Adds a zone match.
282          * @param nameType The name type.
283          * @param matchLength The match length.
284          * @param tzID The time zone ID.
285          * @param status Receives the status
286          * @internal
287          */
288         void addZone(UTimeZoneNameType nameType, int32_t matchLength,
289             const UnicodeString& tzID, UErrorCode& status);
290 
291         /**
292          * Adds a meata zone match.
293          * @param nameType The name type.
294          * @param matchLength The match length.
295          * @param mzID The metazone ID.
296          * @param status Receives the status
297          * @internal
298          */
299         void addMetaZone(UTimeZoneNameType nameType, int32_t matchLength,
300             const UnicodeString& mzID, UErrorCode& status);
301 
302         /**
303          * Returns the number of entries available in this object.
304          * @return The number of entries.
305          * @internal
306          */
307         int32_t size() const;
308 
309         /**
310          * Returns the time zone name type of a match at the specified index.
311          * @param idx The index
312          * @return The time zone name type. If the specified idx is out of range,
313          *      it returns UTZNM_UNKNOWN.
314          * @see UTimeZoneNameType
315          * @internal
316          */
317         UTimeZoneNameType getNameTypeAt(int32_t idx) const;
318 
319         /**
320          * Returns the match length of a match at the specified index.
321          * @param idx The index
322          * @return The match length. If the specified idx is out of range,
323          *      it returns 0.
324          * @internal
325          */
326         int32_t getMatchLengthAt(int32_t idx) const;
327 
328         /**
329          * Gets the zone ID of a match at the specified index.
330          * @param idx The index
331          * @param tzID Receives the zone ID.
332          * @return TRUE if the zone ID was set to tzID.
333          * @internal
334          */
335         UBool getTimeZoneIDAt(int32_t idx, UnicodeString& tzID) const;
336 
337         /**
338          * Gets the metazone ID of a match at the specified index.
339          * @param idx The index
340          * @param mzID Receives the metazone ID
341          * @return TRUE if the meta zone ID was set to mzID.
342          * @internal
343          */
344         UBool getMetaZoneIDAt(int32_t idx, UnicodeString& mzID) const;
345 
346     private:
347         UVector* fMatches;  // vector of MatchEntry
348 
349         UVector* matches(UErrorCode& status);
350     };
351 
352     /**
353      * Finds time zone name prefix matches for the input text at the
354      * given offset and returns a collection of the matches.
355      * @param text The text.
356      * @param start The starting offset within the text.
357      * @param types The set of name types represented by bitwise flags of UTimeZoneNameType enums,
358      *              or UTZNM_UNKNOWN for all name types.
359      * @param status Receives the status.
360      * @return A collection of matches (owned by the caller), or NULL if no matches are found.
361      * @see UTimeZoneNameType
362      * @see MatchInfoCollection
363      * @internal
364      */
365     virtual MatchInfoCollection* find(const UnicodeString& text, int32_t start, uint32_t types, UErrorCode& status) const = 0;
366 
367 private:
368     // No ICU "poor man's RTTI" for this class nor its subclasses.
369     virtual UClassID getDynamicClassID() const;
370 };
371 
372 U_NAMESPACE_END
373 
374 #endif  /* U_HIDE_INTERNAL_API */
375 #endif
376 #endif
377