icuSources/i18n/unicode/vtzone.h

   1 /*
   2 *******************************************************************************
   3 * Copyright (C) 2007-2008, International Business Machines Corporation and         *
   4 * others. All Rights Reserved.                                                *
   5 *******************************************************************************
   6 */
   7 #ifndef VTZONE_H
   8 #define VTZONE_H
   9
  10 #include "unicode/utypes.h"
  11
  12 /**
  13  * \file
  14  * \brief C++ API: RFC2445 VTIMEZONE support
  15  */
  16
  17 #if !UCONFIG_NO_FORMATTING
  18
  19 #include "unicode/basictz.h"
  20
  21 U_NAMESPACE_BEGIN
  22
  23 class VTZWriter;
  24 class VTZReader;
  25 class UVector;
  26
  27 /**
  28  * <code>VTimeZone</code> is a class implementing RFC2445 VTIMEZONE.  You can create a
  29  * <code>VTimeZone</code> instance from a time zone ID supported by <code>TimeZone</code>.
  30  * With the <code>VTimeZone</code> instance created from the ID, you can write out the rule
  31  * in RFC2445 VTIMEZONE format.  Also, you can create a <code>VTimeZone</code> instance
  32  * from RFC2445 VTIMEZONE data stream, which allows you to calculate time
  33  * zone offset by the rules defined by the data.<br><br>
  34  * Note: The consumer of this class reading or writing VTIMEZONE data is responsible to
  35  * decode or encode Non-ASCII text.  Methods reading/writing VTIMEZONE data in this class
  36  * do nothing with MIME encoding.
  37  * @stable ICU 4.0
  38  */
  39 class U_I18N_API VTimeZone : public BasicTimeZone {
  40 public:
  41     /**
  42      * Copy constructor.
  43      * @param source    The <code>VTimeZone</code> object to be copied.
  44      * @stable ICU 4.0
  45      */
  46     VTimeZone(const VTimeZone& source);
  47
  48     /**
  49      * Destructor.
  50      * @stable ICU 4.0
  51      */
  52     virtual ~VTimeZone();
  53
  54     /**
  55      * Assignment operator.
  56      * @param right The object to be copied.
  57      * @stable ICU 4.0
  58      */
  59     VTimeZone& operator=(const VTimeZone& right);
  60
  61     /**
  62      * Return true if the given <code>TimeZone</code> objects are
  63      * semantically equal. Objects of different subclasses are considered unequal.
  64      * @param that  The object to be compared with.
  65      * @return  true if the given <code>TimeZone</code> objects are
  66       *semantically equal.
  67      * @stable ICU 4.0
  68      */
  69     virtual UBool operator==(const TimeZone& that) const;
  70
  71     /**
  72      * Return true if the given <code>TimeZone</code> objects are
  73      * semantically unequal. Objects of different subclasses are considered unequal.
  74      * @param that  The object to be compared with.
  75      * @return  true if the given <code>TimeZone</code> objects are
  76      * semantically unequal.
  77      * @stable ICU 4.0
  78      */
  79     virtual UBool operator!=(const TimeZone& that) const;
  80
  81     /**
  82      * Create a <code>VTimeZone</code> instance by the time zone ID.
  83      * @param ID The time zone ID, such as America/New_York
  84      * @return A <code>VTimeZone</code> object initialized by the time zone ID,
  85      * or NULL when the ID is unknown.
  86      * @stable ICU 4.0
  87      */
  88     static VTimeZone* createVTimeZoneByID(const UnicodeString& ID);
  89
  90     /**
  91      * Create a <code>VTimeZone</code> instance by RFC2445 VTIMEZONE data
  92      *
  93      * @param vtzdata The string including VTIMEZONE data block
  94      * @param status Output param to filled in with a success or an error.
  95      * @return A <code>VTimeZone</code> initialized by the VTIMEZONE data or
  96      * NULL if failed to load the rule from the VTIMEZONE data.
  97      * @stable ICU 4.0
  98      */
  99     static VTimeZone* createVTimeZone(const UnicodeString& vtzdata, UErrorCode& status);
 100
 101     /**
 102      * Gets the RFC2445 TZURL property value.  When a <code>VTimeZone</code> instance was
 103      * created from VTIMEZONE data, the initial value is set by the TZURL property value
 104      * in the data.  Otherwise, the initial value is not set.
 105      * @param url Receives the RFC2445 TZURL property value.
 106      * @return TRUE if TZURL attribute is available and value is set.
 107      * @stable ICU 4.0
 108      */
 109     UBool getTZURL(UnicodeString& url) const;
 110
 111     /**
 112      * Sets the RFC2445 TZURL property value.
 113      * @param url The TZURL property value.
 114      * @stable ICU 4.0
 115      */
 116     void setTZURL(const UnicodeString& url);
 117
 118     /**
 119      * Gets the RFC2445 LAST-MODIFIED property value.  When a <code>VTimeZone</code> instance
 120      * was created from VTIMEZONE data, the initial value is set by the LAST-MODIFIED property
 121      * value in the data.  Otherwise, the initial value is not set.
 122      * @param lastModified Receives the last modified date.
 123      * @return TRUE if lastModified attribute is available and value is set.
 124      * @stable ICU 4.0
 125      */
 126     UBool getLastModified(UDate& lastModified) const;
 127
 128     /**
 129      * Sets the RFC2445 LAST-MODIFIED property value.
 130      * @param lastModified The LAST-MODIFIED date.
 131      * @stable ICU 4.0
 132      */
 133     void setLastModified(UDate lastModified);
 134
 135     /**
 136      * Writes RFC2445 VTIMEZONE data for this time zone
 137      * @param result Output param to filled in with the VTIMEZONE data.
 138      * @param status Output param to filled in with a success or an error.
 139      * @stable ICU 4.0
 140      */
 141     void write(UnicodeString& result, UErrorCode& status) const;
 142
 143     /**
 144      * Writes RFC2445 VTIMEZONE data for this time zone applicalbe
 145      * for dates after the specified start time.
 146      * @param start The start date.
 147      * @param result Output param to filled in with the VTIMEZONE data.
 148      * @param status Output param to filled in with a success or an error.
 149      * @stable ICU 4.0
 150      */
 151     void write(UDate start, UnicodeString& result, UErrorCode& status) /*const*/;
 152
 153     /**
 154      * Writes RFC2445 VTIMEZONE data applicalbe for the specified date.
 155      * Some common iCalendar implementations can only handle a single time
 156      * zone property or a pair of standard and daylight time properties using
 157      * BYDAY rule with day of week (such as BYDAY=1SUN).  This method produce
 158      * the VTIMEZONE data which can be handled these implementations.  The rules
 159      * produced by this method can be used only for calculating time zone offset
 160      * around the specified date.
 161      * @param time The date used for rule extraction.
 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 4.0
 165      */
 166     void writeSimple(UDate time, UnicodeString& result, UErrorCode& status) /*const*/;
 167
 168     /**
 169      * Clones TimeZone objects polymorphically. Clients are responsible for deleting
 170      * the TimeZone object cloned.
 171      * @return   A new copy of this TimeZone object.
 172      * @stable ICU 4.0
 173      */
 174     virtual TimeZone* clone(void) const;
 175
 176     /**
 177      * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add
 178      * to GMT to get local time in this time zone, taking daylight savings time into
 179      * account) as of a particular reference date.  The reference date is used to determine
 180      * whether daylight savings time is in effect and needs to be figured into the offset
 181      * that is returned (in other words, what is the adjusted GMT offset in this time zone
 182      * at this particular date and time?).  For the time zones produced by createTimeZone(),
 183      * the reference data is specified according to the Gregorian calendar, and the date
 184      * and time fields are local standard time.
 185      *
 186      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
 187      * which returns both the raw and the DST offset for a given time. This method
 188      * is retained only for backward compatibility.
 189      *
 190      * @param era        The reference date's era
 191      * @param year       The reference date's year
 192      * @param month      The reference date's month (0-based; 0 is January)
 193      * @param day        The reference date's day-in-month (1-based)
 194      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
 195      * @param millis     The reference date's milliseconds in day, local standard time
 196      * @param status     Output param to filled in with a success or an error.
 197      * @return           The offset in milliseconds to add to GMT to get local time.
 198      * @stable ICU 4.0
 199      */
 200     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
 201                               uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const;
 202
 203     /**
 204      * Gets the time zone offset, for current date, modified in case of
 205      * daylight savings. This is the offset to add *to* UTC to get local time.
 206      *
 207      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
 208      * which returns both the raw and the DST offset for a given time. This method
 209      * is retained only for backward compatibility.
 210      *
 211      * @param era        The reference date's era
 212      * @param year       The reference date's year
 213      * @param month      The reference date's month (0-based; 0 is January)
 214      * @param day        The reference date's day-in-month (1-based)
 215      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
 216      * @param millis     The reference date's milliseconds in day, local standard time
 217      * @param monthLength The length of the given month in days.
 218      * @param status     Output param to filled in with a success or an error.
 219      * @return           The offset in milliseconds to add to GMT to get local time.
 220      * @stable ICU 4.0
 221      */
 222     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
 223                            uint8_t dayOfWeek, int32_t millis,
 224                            int32_t monthLength, UErrorCode& status) const;
 225
 226     /**
 227      * Returns the time zone raw and GMT offset for the given moment
 228      * in time.  Upon return, local-millis = GMT-millis + rawOffset +
 229      * dstOffset.  All computations are performed in the proleptic
 230      * Gregorian calendar.  The default implementation in the TimeZone
 231      * class delegates to the 8-argument getOffset().
 232      *
 233      * @param date moment in time for which to return offsets, in
 234      * units of milliseconds from January 1, 1970 0:00 GMT, either GMT
 235      * time or local wall time, depending on `local'.
 236      * @param local if true, `date' is local wall time; otherwise it
 237      * is in GMT time.
 238      * @param rawOffset output parameter to receive the raw offset, that
 239      * is, the offset not including DST adjustments
 240      * @param dstOffset output parameter to receive the DST offset,
 241      * that is, the offset to be added to `rawOffset' to obtain the
 242      * total offset between local and GMT time. If DST is not in
 243      * effect, this value is zero; otherwise it is a positive value,
 244      * typically one hour.
 245      * @param ec input-output error code
 246      * @stable ICU 4.0
 247      */
 248     virtual void getOffset(UDate date, UBool local, int32_t& rawOffset,
 249                            int32_t& dstOffset, UErrorCode& ec) const;
 250
 251     /**
 252      * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
 253      * to GMT to get local time, before taking daylight savings time into account).
 254      *
 255      * @param offsetMillis  The new raw GMT offset for this time zone.
 256      * @stable ICU 4.0
 257      */
 258     virtual void setRawOffset(int32_t offsetMillis);
 259
 260     /**
 261      * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
 262      * to GMT to get local time, before taking daylight savings time into account).
 263      *
 264      * @return   The TimeZone's raw GMT offset.
 265      * @stable ICU 4.0
 266      */
 267     virtual int32_t getRawOffset(void) const;
 268
 269     /**
 270      * Queries if this time zone uses daylight savings time.
 271      * @return true if this time zone uses daylight savings time,
 272      * false, otherwise.
 273      * @stable ICU 4.0
 274      */
 275     virtual UBool useDaylightTime(void) const;
 276
 277     /**
 278      * Queries if the given date is in daylight savings time in
 279      * this time zone.
 280      * This method is wasteful since it creates a new GregorianCalendar and
 281      * deletes it each time it is called. This is a deprecated method
 282      * and provided only for Java compatibility.
 283      *
 284      * @param date the given UDate.
 285      * @param status Output param filled in with success/error code.
 286      * @return true if the given date is in daylight savings time,
 287      * false, otherwise.
 288      * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead.
 289      */
 290     virtual UBool inDaylightTime(UDate date, UErrorCode& status) const;
 291
 292     /**
 293      * Returns true if this zone has the same rule and offset as another zone.
 294      * That is, if this zone differs only in ID, if at all.
 295      * @param other the <code>TimeZone</code> object to be compared with
 296      * @return true if the given zone is the same as this one,
 297      * with the possible exception of the ID
 298      * @stable ICU 4.0
 299      */
 300     virtual UBool hasSameRules(const TimeZone& other) const;
 301
 302     /**
 303      * Gets the first time zone transition after the base time.
 304      * @param base      The base time.
 305      * @param inclusive Whether the base time is inclusive or not.
 306      * @param result    Receives the first transition after the base time.
 307      * @return  TRUE if the transition is found.
 308      * @stable ICU 4.0
 309      */
 310     virtual UBool getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) /*const*/;
 311
 312     /**
 313      * Gets the most recent time zone transition before the base time.
 314      * @param base      The base time.
 315      * @param inclusive Whether the base time is inclusive or not.
 316      * @param result    Receives the most recent transition before the base time.
 317      * @return  TRUE if the transition is found.
 318      * @stable ICU 4.0
 319      */
 320     virtual UBool getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) /*const*/;
 321
 322     /**
 323      * Returns the number of <code>TimeZoneRule</code>s which represents time transitions,
 324      * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except
 325      * <code>InitialTimeZoneRule</code>.  The return value range is 0 or any positive value.
 326      * @param status    Receives error status code.
 327      * @return The number of <code>TimeZoneRule</code>s representing time transitions.
 328      * @stable ICU 4.0
 329      */
 330     virtual int32_t countTransitionRules(UErrorCode& status) /*const*/;
 331
 332     /**
 333      * Gets the <code>InitialTimeZoneRule</code> and the set of <code>TimeZoneRule</code>
 334      * which represent time transitions for this time zone.  On successful return,
 335      * the argument initial points to non-NULL <code>InitialTimeZoneRule</code> and
 336      * the array trsrules is filled with 0 or multiple <code>TimeZoneRule</code>
 337      * instances up to the size specified by trscount.  The results are referencing the
 338      * rule instance held by this time zone instance.  Therefore, after this time zone
 339      * is destructed, they are no longer available.
 340      * @param initial       Receives the initial timezone rule
 341      * @param trsrules      Receives the timezone transition rules
 342      * @param trscount      On input, specify the size of the array 'transitions' receiving
 343      *                      the timezone transition rules.  On output, actual number of
 344      *                      rules filled in the array will be set.
 345      * @param status        Receives error status code.
 346      * @stable ICU 4.0
 347      */
 348     virtual void getTimeZoneRules(const InitialTimeZoneRule*& initial,
 349         const TimeZoneRule* trsrules[], int32_t& trscount, UErrorCode& status) /*const*/;
 350
 351 private:
 352     enum { DEFAULT_VTIMEZONE_LINES = 100 };
 353
 354     /**
 355      * Default constructor.
 356      */
 357     VTimeZone();
 358     static VTimeZone* createVTimeZone(VTZReader* reader);
 359     void write(VTZWriter& writer, UErrorCode& status) const;
 360     void write(UDate start, VTZWriter& writer, UErrorCode& status) /*const*/;
 361     void writeSimple(UDate time, VTZWriter& writer, UErrorCode& status) /*const*/;
 362     void load(VTZReader& reader, UErrorCode& status);
 363     void parse(UErrorCode& status);
 364
 365     void writeZone(VTZWriter& w, BasicTimeZone& basictz, UVector* customProps,
 366         UErrorCode& status) const;
 367
 368     void writeHeaders(VTZWriter& w, UErrorCode& status) const;
 369     void writeFooter(VTZWriter& writer, UErrorCode& status) const;
 370
 371     void writeZonePropsByTime(VTZWriter& writer, UBool isDst, const UnicodeString& tzname,
 372                               int32_t fromOffset, int32_t toOffset, UDate time, UBool withRDATE,
 373                               UErrorCode& status) const;
 374     void writeZonePropsByDOM(VTZWriter& writer, UBool isDst, const UnicodeString& tzname,
 375                              int32_t fromOffset, int32_t toOffset,
 376                              int32_t month, int32_t dayOfMonth, UDate startTime, UDate untilTime,
 377                              UErrorCode& status) const;
 378     void writeZonePropsByDOW(VTZWriter& writer, UBool isDst, const UnicodeString& tzname,
 379                              int32_t fromOffset, int32_t toOffset,
 380                              int32_t month, int32_t weekInMonth, int32_t dayOfWeek,
 381                              UDate startTime, UDate untilTime, UErrorCode& status) const;
 382     void writeZonePropsByDOW_GEQ_DOM(VTZWriter& writer, UBool isDst, const UnicodeString& tzname,
 383                                      int32_t fromOffset, int32_t toOffset,
 384                                      int32_t month, int32_t dayOfMonth, int32_t dayOfWeek,
 385                                      UDate startTime, UDate untilTime, UErrorCode& status) const;
 386     void writeZonePropsByDOW_GEQ_DOM_sub(VTZWriter& writer, int32_t month, int32_t dayOfMonth,
 387                                          int32_t dayOfWeek, int32_t numDays,
 388                                          UDate untilTime, int32_t fromOffset, UErrorCode& status) const;
 389     void writeZonePropsByDOW_LEQ_DOM(VTZWriter& writer, UBool isDst, const UnicodeString& tzname,
 390                                      int32_t fromOffset, int32_t toOffset,
 391                                      int32_t month, int32_t dayOfMonth, int32_t dayOfWeek,
 392                                      UDate startTime, UDate untilTime, UErrorCode& status) const;
 393     void writeFinalRule(VTZWriter& writer, UBool isDst, const AnnualTimeZoneRule* rule,
 394                         int32_t fromRawOffset, int32_t fromDSTSavings,
 395                         UDate startTime, UErrorCode& status) const;
 396
 397     void beginZoneProps(VTZWriter& writer, UBool isDst, const UnicodeString& tzname,
 398                         int32_t fromOffset, int32_t toOffset, UDate startTime, UErrorCode& status) const;
 399     void endZoneProps(VTZWriter& writer, UBool isDst, UErrorCode& status) const;
 400     void beginRRULE(VTZWriter& writer, int32_t month, UErrorCode& status) const;
 401     void appendUNTIL(VTZWriter& writer, const UnicodeString& until, UErrorCode& status) const;
 402
 403     BasicTimeZone   *tz;
 404     UVector         *vtzlines;
 405     UnicodeString   tzurl;
 406     UDate           lastmod;
 407     UnicodeString   olsonzid;
 408     UnicodeString   icutzver;
 409
 410 public:
 411     /**
 412      * Return the class ID for this class. This is useful only for comparing to
 413      * a return value from getDynamicClassID(). For example:
 414      * <pre>
 415      * .   Base* polymorphic_pointer = createPolymorphicObject();
 416      * .   if (polymorphic_pointer->getDynamicClassID() ==
 417      * .       erived::getStaticClassID()) ...
 418      * </pre>
 419      * @return          The class ID for all objects of this class.
 420      * @stable ICU 4.0
 421      */
 422     static UClassID U_EXPORT2 getStaticClassID(void);
 423
 424     /**
 425      * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
 426      * method is to implement a simple version of RTTI, since not all C++
 427      * compilers support genuine RTTI. Polymorphic operator==() and clone()
 428      * methods call this method.
 429      *
 430      * @return          The class ID for this object. All objects of a
 431      *                  given class have the same class ID.  Objects of
 432      *                  other classes have different class IDs.
 433      * @stable ICU 4.0
 434      */
 435     virtual UClassID getDynamicClassID(void) const;
 436 };
 437
 438 U_NAMESPACE_END
 439
 440 #endif /* #if !UCONFIG_NO_FORMATTING */
 441
 442 #endif // VTZONE_H
 443 //eof