icuSources/i18n/unicode/vtzone.h

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 *******************************************************************************
   5 * Copyright (C) 2007-2013, International Business Machines Corporation and
   6 * others. All Rights Reserved.
   7 *******************************************************************************
   8 */
   9 #ifndef VTZONE_H
  10 #define VTZONE_H
  11
  12 #include "unicode/utypes.h"
  13
  14 /**
  15  * \file
  16  * \brief C++ API: RFC2445 VTIMEZONE support
  17  */
  18
  19 #if !UCONFIG_NO_FORMATTING
  20
  21 #include "unicode/basictz.h"
  22
  23 #if U_SHOW_CPLUSPLUS_API
  24 U_NAMESPACE_BEGIN
  25
  26 class VTZWriter;
  27 class VTZReader;
  28 class UVector;
  29
  30 /**
  31  * <code>VTimeZone</code> is a class implementing RFC2445 VTIMEZONE.  You can create a
  32  * <code>VTimeZone</code> instance from a time zone ID supported by <code>TimeZone</code>.
  33  * With the <code>VTimeZone</code> instance created from the ID, you can write out the rule
  34  * in RFC2445 VTIMEZONE format.  Also, you can create a <code>VTimeZone</code> instance
  35  * from RFC2445 VTIMEZONE data stream, which allows you to calculate time
  36  * zone offset by the rules defined by the data. Or, you can create a
  37  * <code>VTimeZone</code> from any other ICU <code>BasicTimeZone</code>.
  38  * <br><br>
  39  * Note: The consumer of this class reading or writing VTIMEZONE data is responsible to
  40  * decode or encode Non-ASCII text.  Methods reading/writing VTIMEZONE data in this class
  41  * do nothing with MIME encoding.
  42  * @stable ICU 3.8
  43  */
  44 class U_I18N_API VTimeZone : public BasicTimeZone {
  45 public:
  46     /**
  47      * Copy constructor.
  48      * @param source    The <code>VTimeZone</code> object to be copied.
  49      * @stable ICU 3.8
  50      */
  51     VTimeZone(const VTimeZone& source);
  52
  53     /**
  54      * Destructor.
  55      * @stable ICU 3.8
  56      */
  57     virtual ~VTimeZone();
  58
  59     /**
  60      * Assignment operator.
  61      * @param right The object to be copied.
  62      * @stable ICU 3.8
  63      */
  64     VTimeZone& operator=(const VTimeZone& right);
  65
  66     /**
  67      * Return true if the given <code>TimeZone</code> objects are
  68      * semantically equal. Objects of different subclasses are considered unequal.
  69      * @param that  The object to be compared with.
  70      * @return  true if the given <code>TimeZone</code> objects are
  71       *semantically equal.
  72      * @stable ICU 3.8
  73      */
  74     virtual UBool operator==(const TimeZone& that) const;
  75
  76     /**
  77      * Return true if the given <code>TimeZone</code> objects are
  78      * semantically unequal. Objects of different subclasses are considered unequal.
  79      * @param that  The object to be compared with.
  80      * @return  true if the given <code>TimeZone</code> objects are
  81      * semantically unequal.
  82      * @stable ICU 3.8
  83      */
  84     virtual UBool operator!=(const TimeZone& that) const;
  85
  86     /**
  87      * Create a <code>VTimeZone</code> instance by the time zone ID.
  88      * @param ID The time zone ID, such as America/New_York
  89      * @return A <code>VTimeZone</code> object initialized by the time zone ID,
  90      * or NULL when the ID is unknown.
  91      * @stable ICU 3.8
  92      */
  93     static VTimeZone* createVTimeZoneByID(const UnicodeString& ID);
  94
  95     /**
  96      * Create a <code>VTimeZone</code> instance using a basic time zone.
  97      * @param basicTZ The basic time zone instance
  98      * @param status Output param to filled in with a success or an error.
  99      * @return A <code>VTimeZone</code> object initialized by the basic time zone.
 100      * @stable ICU 4.6
 101      */
 102     static VTimeZone* createVTimeZoneFromBasicTimeZone(const BasicTimeZone& basicTZ,
 103                                                        UErrorCode &status);
 104
 105     /**
 106      * Create a <code>VTimeZone</code> instance by RFC2445 VTIMEZONE data
 107      *
 108      * @param vtzdata The string including VTIMEZONE data block
 109      * @param status Output param to filled in with a success or an error.
 110      * @return A <code>VTimeZone</code> initialized by the VTIMEZONE data or
 111      * NULL if failed to load the rule from the VTIMEZONE data.
 112      * @stable ICU 3.8
 113      */
 114     static VTimeZone* createVTimeZone(const UnicodeString& vtzdata, UErrorCode& status);
 115
 116     /**
 117      * Gets the RFC2445 TZURL property value.  When a <code>VTimeZone</code> instance was
 118      * created from VTIMEZONE data, the initial value is set by the TZURL property value
 119      * in the data.  Otherwise, the initial value is not set.
 120      * @param url Receives the RFC2445 TZURL property value.
 121      * @return TRUE if TZURL attribute is available and value is set.
 122      * @stable ICU 3.8
 123      */
 124     UBool getTZURL(UnicodeString& url) const;
 125
 126     /**
 127      * Sets the RFC2445 TZURL property value.
 128      * @param url The TZURL property value.
 129      * @stable ICU 3.8
 130      */
 131     void setTZURL(const UnicodeString& url);
 132
 133     /**
 134      * Gets the RFC2445 LAST-MODIFIED property value.  When a <code>VTimeZone</code> instance
 135      * was created from VTIMEZONE data, the initial value is set by the LAST-MODIFIED property
 136      * value in the data.  Otherwise, the initial value is not set.
 137      * @param lastModified Receives the last modified date.
 138      * @return TRUE if lastModified attribute is available and value is set.
 139      * @stable ICU 3.8
 140      */
 141     UBool getLastModified(UDate& lastModified) const;
 142
 143     /**
 144      * Sets the RFC2445 LAST-MODIFIED property value.
 145      * @param lastModified The LAST-MODIFIED date.
 146      * @stable ICU 3.8
 147      */
 148     void setLastModified(UDate lastModified);
 149
 150     /**
 151      * Writes RFC2445 VTIMEZONE data for this time zone
 152      * @param result Output param to filled in with the VTIMEZONE data.
 153      * @param status Output param to filled in with a success or an error.
 154      * @stable ICU 3.8
 155      */
 156     void write(UnicodeString& result, UErrorCode& status) const;
 157
 158     /**
 159      * Writes RFC2445 VTIMEZONE data for this time zone applicalbe
 160      * for dates after the specified start time.
 161      * @param start The start date.
 162      * @param result Output param to filled in with the VTIMEZONE data.
 163      * @param status Output param to filled in with a success or an error.
 164      * @stable ICU 3.8
 165      */
 166     void write(UDate start, UnicodeString& result, UErrorCode& status) const;
 167
 168     /**
 169      * Writes RFC2445 VTIMEZONE data applicalbe for the specified date.
 170      * Some common iCalendar implementations can only handle a single time
 171      * zone property or a pair of standard and daylight time properties using
 172      * BYDAY rule with day of week (such as BYDAY=1SUN).  This method produce
 173      * the VTIMEZONE data which can be handled these implementations.  The rules
 174      * produced by this method can be used only for calculating time zone offset
 175      * around the specified date.
 176      * @param time The date used for rule extraction.
 177      * @param result Output param to filled in with the VTIMEZONE data.
 178      * @param status Output param to filled in with a success or an error.
 179      * @stable ICU 3.8
 180      */
 181     void writeSimple(UDate time, UnicodeString& result, UErrorCode& status) const;
 182
 183     /**
 184      * Clones TimeZone objects polymorphically. Clients are responsible for deleting
 185      * the TimeZone object cloned.
 186      * @return   A new copy of this TimeZone object.
 187      * @stable ICU 3.8
 188      */
 189     virtual TimeZone* clone(void) const;
 190
 191     /**
 192      * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add
 193      * to GMT to get local time in this time zone, taking daylight savings time into
 194      * account) as of a particular reference date.  The reference date is used to determine
 195      * whether daylight savings time is in effect and needs to be figured into the offset
 196      * that is returned (in other words, what is the adjusted GMT offset in this time zone
 197      * at this particular date and time?).  For the time zones produced by createTimeZone(),
 198      * the reference data is specified according to the Gregorian calendar, and the date
 199      * and time fields are local standard time.
 200      *
 201      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
 202      * which returns both the raw and the DST offset for a given time. This method
 203      * is retained only for backward compatibility.
 204      *
 205      * @param era        The reference date's era
 206      * @param year       The reference date's year
 207      * @param month      The reference date's month (0-based; 0 is January)
 208      * @param day        The reference date's day-in-month (1-based)
 209      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
 210      * @param millis     The reference date's milliseconds in day, local standard time
 211      * @param status     Output param to filled in with a success or an error.
 212      * @return           The offset in milliseconds to add to GMT to get local time.
 213      * @stable ICU 3.8
 214      */
 215     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
 216                               uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const;
 217
 218     /**
 219      * Gets the time zone offset, for current date, modified in case of
 220      * daylight savings. This is the offset to add *to* UTC to get local time.
 221      *
 222      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
 223      * which returns both the raw and the DST offset for a given time. This method
 224      * is retained only for backward compatibility.
 225      *
 226      * @param era        The reference date's era
 227      * @param year       The reference date's year
 228      * @param month      The reference date's month (0-based; 0 is January)
 229      * @param day        The reference date's day-in-month (1-based)
 230      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
 231      * @param millis     The reference date's milliseconds in day, local standard time
 232      * @param monthLength The length of the given month in days.
 233      * @param status     Output param to filled in with a success or an error.
 234      * @return           The offset in milliseconds to add to GMT to get local time.
 235      * @stable ICU 3.8
 236      */
 237     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
 238                            uint8_t dayOfWeek, int32_t millis,
 239                            int32_t monthLength, UErrorCode& status) const;
 240
 241     /**
 242      * Returns the time zone raw and GMT offset for the given moment
 243      * in time.  Upon return, local-millis = GMT-millis + rawOffset +
 244      * dstOffset.  All computations are performed in the proleptic
 245      * Gregorian calendar.  The default implementation in the TimeZone
 246      * class delegates to the 8-argument getOffset().
 247      *
 248      * @param date moment in time for which to return offsets, in
 249      * units of milliseconds from January 1, 1970 0:00 GMT, either GMT
 250      * time or local wall time, depending on `local'.
 251      * @param local if true, `date' is local wall time; otherwise it
 252      * is in GMT time.
 253      * @param rawOffset output parameter to receive the raw offset, that
 254      * is, the offset not including DST adjustments
 255      * @param dstOffset output parameter to receive the DST offset,
 256      * that is, the offset to be added to `rawOffset' to obtain the
 257      * total offset between local and GMT time. If DST is not in
 258      * effect, this value is zero; otherwise it is a positive value,
 259      * typically one hour.
 260      * @param ec input-output error code
 261      * @stable ICU 3.8
 262      */
 263     virtual void getOffset(UDate date, UBool local, int32_t& rawOffset,
 264                            int32_t& dstOffset, UErrorCode& ec) const;
 265
 266     /**
 267      * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
 268      * to GMT to get local time, before taking daylight savings time into account).
 269      *
 270      * @param offsetMillis  The new raw GMT offset for this time zone.
 271      * @stable ICU 3.8
 272      */
 273     virtual void setRawOffset(int32_t offsetMillis);
 274
 275     /**
 276      * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
 277      * to GMT to get local time, before taking daylight savings time into account).
 278      *
 279      * @return   The TimeZone's raw GMT offset.
 280      * @stable ICU 3.8
 281      */
 282     virtual int32_t getRawOffset(void) const;
 283
 284     /**
 285      * Queries if this time zone uses daylight savings time.
 286      * @return true if this time zone uses daylight savings time,
 287      * false, otherwise.
 288      * @stable ICU 3.8
 289      */
 290     virtual UBool useDaylightTime(void) const;
 291
 292     /**
 293      * Queries if the given date is in daylight savings time in
 294      * this time zone.
 295      * This method is wasteful since it creates a new GregorianCalendar and
 296      * deletes it each time it is called. This is a deprecated method
 297      * and provided only for Java compatibility.
 298      *
 299      * @param date the given UDate.
 300      * @param status Output param filled in with success/error code.
 301      * @return true if the given date is in daylight savings time,
 302      * false, otherwise.
 303      * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead.
 304      */
 305     virtual UBool inDaylightTime(UDate date, UErrorCode& status) const;
 306
 307     /**
 308      * Returns true if this zone has the same rule and offset as another zone.
 309      * That is, if this zone differs only in ID, if at all.
 310      * @param other the <code>TimeZone</code> object to be compared with
 311      * @return true if the given zone is the same as this one,
 312      * with the possible exception of the ID
 313      * @stable ICU 3.8
 314      */
 315     virtual UBool hasSameRules(const TimeZone& other) const;
 316
 317     /**
 318      * Gets the first time zone transition after the base time.
 319      * @param base      The base time.
 320      * @param inclusive Whether the base time is inclusive or not.
 321      * @param result    Receives the first transition after the base time.
 322      * @return  TRUE if the transition is found.
 323      * @stable ICU 3.8
 324      */
 325     virtual UBool getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const;
 326
 327     /**
 328      * Gets the most recent time zone transition before the base time.
 329      * @param base      The base time.
 330      * @param inclusive Whether the base time is inclusive or not.
 331      * @param result    Receives the most recent transition before the base time.
 332      * @return  TRUE if the transition is found.
 333      * @stable ICU 3.8
 334      */
 335     virtual UBool getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const;
 336
 337     /**
 338      * Returns the number of <code>TimeZoneRule</code>s which represents time transitions,
 339      * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except
 340      * <code>InitialTimeZoneRule</code>.  The return value range is 0 or any positive value.
 341      * @param status    Receives error status code.
 342      * @return The number of <code>TimeZoneRule</code>s representing time transitions.
 343      * @stable ICU 3.8
 344      */
 345     virtual int32_t countTransitionRules(UErrorCode& status) const;
 346
 347     /**
 348      * Gets the <code>InitialTimeZoneRule</code> and the set of <code>TimeZoneRule</code>
 349      * which represent time transitions for this time zone.  On successful return,
 350      * the argument initial points to non-NULL <code>InitialTimeZoneRule</code> and
 351      * the array trsrules is filled with 0 or multiple <code>TimeZoneRule</code>
 352      * instances up to the size specified by trscount.  The results are referencing the
 353      * rule instance held by this time zone instance.  Therefore, after this time zone
 354      * is destructed, they are no longer available.
 355      * @param initial       Receives the initial timezone rule
 356      * @param trsrules      Receives the timezone transition rules
 357      * @param trscount      On input, specify the size of the array 'transitions' receiving
 358      *                      the timezone transition rules.  On output, actual number of
 359      *                      rules filled in the array will be set.
 360      * @param status        Receives error status code.
 361      * @stable ICU 3.8
 362      */
 363     virtual void getTimeZoneRules(const InitialTimeZoneRule*& initial,
 364         const TimeZoneRule* trsrules[], int32_t& trscount, UErrorCode& status) const;
 365
 366 private:
 367     enum { DEFAULT_VTIMEZONE_LINES = 100 };
 368
 369     /**
 370      * Default constructor.
 371      */
 372     VTimeZone();
 373     static VTimeZone* createVTimeZone(VTZReader* reader);
 374     void write(VTZWriter& writer, UErrorCode& status) const;
 375     void write(UDate start, VTZWriter& writer, UErrorCode& status) const;
 376     void writeSimple(UDate time, VTZWriter& writer, UErrorCode& status) const;
 377     void load(VTZReader& reader, UErrorCode& status);
 378     void parse(UErrorCode& status);
 379
 380     void writeZone(VTZWriter& w, BasicTimeZone& basictz, UVector* customProps,
 381         UErrorCode& status) const;
 382
 383     void writeHeaders(VTZWriter& w, UErrorCode& status) const;
 384     void writeFooter(VTZWriter& writer, UErrorCode& status) const;
 385
 386     void writeZonePropsByTime(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
 387                               int32_t fromOffset, int32_t toOffset, UDate time, UBool withRDATE,
 388                               UErrorCode& status) const;
 389     void writeZonePropsByDOM(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
 390                              int32_t fromOffset, int32_t toOffset,
 391                              int32_t month, int32_t dayOfMonth, UDate startTime, UDate untilTime,
 392                              UErrorCode& status) const;
 393     void writeZonePropsByDOW(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
 394                              int32_t fromOffset, int32_t toOffset,
 395                              int32_t month, int32_t weekInMonth, int32_t dayOfWeek,
 396                              UDate startTime, UDate untilTime, UErrorCode& status) const;
 397     void writeZonePropsByDOW_GEQ_DOM(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
 398                                      int32_t fromOffset, int32_t toOffset,
 399                                      int32_t month, int32_t dayOfMonth, int32_t dayOfWeek,
 400                                      UDate startTime, UDate untilTime, UErrorCode& status) const;
 401     void writeZonePropsByDOW_GEQ_DOM_sub(VTZWriter& writer, int32_t month, int32_t dayOfMonth,
 402                                          int32_t dayOfWeek, int32_t numDays,
 403                                          UDate untilTime, int32_t fromOffset, UErrorCode& status) const;
 404     void writeZonePropsByDOW_LEQ_DOM(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
 405                                      int32_t fromOffset, int32_t toOffset,
 406                                      int32_t month, int32_t dayOfMonth, int32_t dayOfWeek,
 407                                      UDate startTime, UDate untilTime, UErrorCode& status) const;
 408     void writeFinalRule(VTZWriter& writer, UBool isDst, const AnnualTimeZoneRule* rule,
 409                         int32_t fromRawOffset, int32_t fromDSTSavings,
 410                         UDate startTime, UErrorCode& status) const;
 411
 412     void beginZoneProps(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
 413                         int32_t fromOffset, int32_t toOffset, UDate startTime, UErrorCode& status) const;
 414     void endZoneProps(VTZWriter& writer, UBool isDst, UErrorCode& status) const;
 415     void beginRRULE(VTZWriter& writer, int32_t month, UErrorCode& status) const;
 416     void appendUNTIL(VTZWriter& writer, const UnicodeString& until, UErrorCode& status) const;
 417
 418     BasicTimeZone   *tz;
 419     UVector         *vtzlines;
 420     UnicodeString   tzurl;
 421     UDate           lastmod;
 422     UnicodeString   olsonzid;
 423     UnicodeString   icutzver;
 424
 425 public:
 426     /**
 427      * Return the class ID for this class. This is useful only for comparing to
 428      * a return value from getDynamicClassID(). For example:
 429      * <pre>
 430      * .   Base* polymorphic_pointer = createPolymorphicObject();
 431      * .   if (polymorphic_pointer->getDynamicClassID() ==
 432      * .       erived::getStaticClassID()) ...
 433      * </pre>
 434      * @return          The class ID for all objects of this class.
 435      * @stable ICU 3.8
 436      */
 437     static UClassID U_EXPORT2 getStaticClassID(void);
 438
 439     /**
 440      * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
 441      * method is to implement a simple version of RTTI, since not all C++
 442      * compilers support genuine RTTI. Polymorphic operator==() and clone()
 443      * methods call this method.
 444      *
 445      * @return          The class ID for this object. All objects of a
 446      *                  given class have the same class ID.  Objects of
 447      *                  other classes have different class IDs.
 448      * @stable ICU 3.8
 449      */
 450     virtual UClassID getDynamicClassID(void) const;
 451 };
 452
 453 U_NAMESPACE_END
 454 #endif // U_SHOW_CPLUSPLUS_API
 455
 456 #endif /* #if !UCONFIG_NO_FORMATTING */
 457
 458 #endif // VTZONE_H
 459 //eof