Check in the pristine copy of ICU 4.6...

icu46/source/i18n/simpletz.cpp

+/*
+ *******************************************************************************
+ * Copyright (C) 1997-2010, International Business Machines Corporation and
+ * others. All Rights Reserved.
+ *******************************************************************************
+ *
+ * File SIMPLETZ.H
+ *
+ * Modification History:
+ *
+ *   Date        Name        Description
+ *   12/05/96    clhuang     Creation.
+ *   04/21/97    aliu        Fixed miscellaneous bugs found by inspection and
+ *                           testing.
+ *   07/29/97    aliu        Ported source bodies back from Java version with
+ *                           numerous feature enhancements and bug fixes.
+ *   08/10/98    stephen     JDK 1.2 sync.
+ *   09/17/98    stephen     Fixed getOffset() for last hour of year and DST
+ *   12/02/99    aliu        Added TimeMode and constructor and setStart/EndRule
+ *                           methods that take TimeMode. Whitespace cleanup.
+ ********************************************************************************
+ */
+
+#include <typeinfo>  // for 'typeid' to work
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_FORMATTING
+
+#include "unicode/simpletz.h"
+#include "unicode/gregocal.h"
+#include "unicode/smpdtfmt.h"
+
+#include "gregoimp.h"
+
+U_NAMESPACE_BEGIN
+
+UOBJECT_DEFINE_RTTI_IMPLEMENTATION(SimpleTimeZone)
+
+// Use only for decodeStartRule() and decodeEndRule() where the year is not
+// available. Set February to 29 days to accomodate rules with that date
+// and day-of-week-on-or-before-that-date mode (DOW_LE_DOM_MODE).
+// The compareToRule() method adjusts to February 28 in non-leap years.
+//
+// For actual getOffset() calculations, use Grego::monthLength() and
+// Grego::previousMonthLength() which take leap years into account.
+// We handle leap years assuming always
+// Gregorian, since we know they didn't have daylight time when
+// Gregorian calendar started.
+const int8_t SimpleTimeZone::STATICMONTHLENGTH[] = {31,29,31,30,31,30,31,31,30,31,30,31};
+
+static const UChar DST_STR[] = {0x0028,0x0044,0x0053,0x0054,0x0029,0}; // "(DST)"
+static const UChar STD_STR[] = {0x0028,0x0053,0x0054,0x0044,0x0029,0}; // "(STD)"
+
+
+// *****************************************************************************
+// class SimpleTimeZone
+// *****************************************************************************
+
+
+SimpleTimeZone::SimpleTimeZone(int32_t rawOffsetGMT, const UnicodeString& ID)
+:   BasicTimeZone(ID),
+    startMonth(0),
+    startDay(0),
+    startDayOfWeek(0),
+    startTime(0),
+    startTimeMode(WALL_TIME),
+    endTimeMode(WALL_TIME),
+    endMonth(0),
+    endDay(0),
+    endDayOfWeek(0),
+    endTime(0),
+    startYear(0),
+    rawOffset(rawOffsetGMT),
+    useDaylight(FALSE),
+    startMode(DOM_MODE),
+    endMode(DOM_MODE),
+    dstSavings(U_MILLIS_PER_HOUR)
+{
+    clearTransitionRules();
+}
+
+// -------------------------------------
+
+SimpleTimeZone::SimpleTimeZone(int32_t rawOffsetGMT, const UnicodeString& ID,
+    int8_t savingsStartMonth, int8_t savingsStartDay,
+    int8_t savingsStartDayOfWeek, int32_t savingsStartTime,
+    int8_t savingsEndMonth, int8_t savingsEndDay,
+    int8_t savingsEndDayOfWeek, int32_t savingsEndTime,
+    UErrorCode& status)
+:   BasicTimeZone(ID)
+{
+    clearTransitionRules();
+    construct(rawOffsetGMT,
+              savingsStartMonth, savingsStartDay, savingsStartDayOfWeek,
+              savingsStartTime, WALL_TIME,
+              savingsEndMonth, savingsEndDay, savingsEndDayOfWeek,
+              savingsEndTime, WALL_TIME,
+              U_MILLIS_PER_HOUR, status);
+}
+
+// -------------------------------------
+
+SimpleTimeZone::SimpleTimeZone(int32_t rawOffsetGMT, const UnicodeString& ID,
+    int8_t savingsStartMonth, int8_t savingsStartDay,
+    int8_t savingsStartDayOfWeek, int32_t savingsStartTime,
+    int8_t savingsEndMonth, int8_t savingsEndDay,
+    int8_t savingsEndDayOfWeek, int32_t savingsEndTime,
+    int32_t savingsDST, UErrorCode& status)
+:   BasicTimeZone(ID)
+{
+    clearTransitionRules();
+    construct(rawOffsetGMT,
+              savingsStartMonth, savingsStartDay, savingsStartDayOfWeek,
+              savingsStartTime, WALL_TIME,
+              savingsEndMonth, savingsEndDay, savingsEndDayOfWeek,
+              savingsEndTime, WALL_TIME,
+              savingsDST, status);
+}
+
+// -------------------------------------
+
+SimpleTimeZone::SimpleTimeZone(int32_t rawOffsetGMT, const UnicodeString& ID,
+    int8_t savingsStartMonth, int8_t savingsStartDay,
+    int8_t savingsStartDayOfWeek, int32_t savingsStartTime,
+    TimeMode savingsStartTimeMode,
+    int8_t savingsEndMonth, int8_t savingsEndDay,
+    int8_t savingsEndDayOfWeek, int32_t savingsEndTime,
+    TimeMode savingsEndTimeMode,
+    int32_t savingsDST, UErrorCode& status)
+:   BasicTimeZone(ID)
+{
+    clearTransitionRules();
+    construct(rawOffsetGMT,
+              savingsStartMonth, savingsStartDay, savingsStartDayOfWeek,
+              savingsStartTime, savingsStartTimeMode,
+              savingsEndMonth, savingsEndDay, savingsEndDayOfWeek,
+              savingsEndTime, savingsEndTimeMode,
+              savingsDST, status);
+}
+
+/**
+ * Internal construction method.
+ */
+void SimpleTimeZone::construct(int32_t rawOffsetGMT,
+                               int8_t savingsStartMonth,
+                               int8_t savingsStartDay,
+                               int8_t savingsStartDayOfWeek,
+                               int32_t savingsStartTime,
+                               TimeMode savingsStartTimeMode,
+                               int8_t savingsEndMonth,
+                               int8_t savingsEndDay,
+                               int8_t savingsEndDayOfWeek,
+                               int32_t savingsEndTime,
+                               TimeMode savingsEndTimeMode,
+                               int32_t savingsDST,
+                               UErrorCode& status)
+{
+    this->rawOffset      = rawOffsetGMT;
+    this->startMonth     = savingsStartMonth;
+    this->startDay       = savingsStartDay;
+    this->startDayOfWeek = savingsStartDayOfWeek;
+    this->startTime      = savingsStartTime;
+    this->startTimeMode  = savingsStartTimeMode;
+    this->endMonth       = savingsEndMonth;
+    this->endDay         = savingsEndDay;
+    this->endDayOfWeek   = savingsEndDayOfWeek;
+    this->endTime        = savingsEndTime;
+    this->endTimeMode    = savingsEndTimeMode;
+    this->dstSavings     = savingsDST;
+    this->startYear      = 0;
+    this->startMode      = DOM_MODE;
+    this->endMode        = DOM_MODE;
+
+    decodeRules(status);
+
+    if (savingsDST <= 0) {
+        status = U_ILLEGAL_ARGUMENT_ERROR;
+    }
+}
+
+// -------------------------------------
+
+SimpleTimeZone::~SimpleTimeZone()
+{
+    deleteTransitionRules();
+}
+
+// -------------------------------------
+
+// Called by TimeZone::createDefault(), then clone() inside a Mutex - be careful.
+SimpleTimeZone::SimpleTimeZone(const SimpleTimeZone &source)
+:   BasicTimeZone(source)
+{
+    *this = source;
+}
+
+// -------------------------------------
+
+// Called by TimeZone::createDefault(), then clone() inside a Mutex - be careful.
+SimpleTimeZone &
+SimpleTimeZone::operator=(const SimpleTimeZone &right)
+{
+    if (this != &right)
+    {
+        TimeZone::operator=(right);
+        rawOffset      = right.rawOffset;
+        startMonth     = right.startMonth;
+        startDay       = right.startDay;
+        startDayOfWeek = right.startDayOfWeek;
+        startTime      = right.startTime;
+        startTimeMode  = right.startTimeMode;
+        startMode      = right.startMode;
+        endMonth       = right.endMonth;
+        endDay         = right.endDay;
+        endDayOfWeek   = right.endDayOfWeek;
+        endTime        = right.endTime;
+        endTimeMode    = right.endTimeMode;
+        endMode        = right.endMode;
+        startYear      = right.startYear;
+        dstSavings     = right.dstSavings;
+        useDaylight    = right.useDaylight;
+        clearTransitionRules();
+    }
+    return *this;
+}
+
+// -------------------------------------
+
+UBool
+SimpleTimeZone::operator==(const TimeZone& that) const
+{
+    return ((this == &that) ||
+            (typeid(*this) == typeid(that) &&
+            TimeZone::operator==(that) &&
+            hasSameRules(that)));
+}
+
+// -------------------------------------
+
+// Called by TimeZone::createDefault() inside a Mutex - be careful.
+TimeZone*
+SimpleTimeZone::clone() const
+{
+    return new SimpleTimeZone(*this);
+}
+
+// -------------------------------------
+
+/**
+ * Sets the daylight savings starting year, that is, the year this time zone began
+ * observing its specified daylight savings time rules.  The time zone is considered
+ * not to observe daylight savings time prior to that year; SimpleTimeZone doesn't
+ * support historical daylight-savings-time rules.
+ * @param year the daylight savings starting year.
+ */
+void
+SimpleTimeZone::setStartYear(int32_t year)
+{
+    startYear = year;
+    transitionRulesInitialized = FALSE;
+}
+
+// -------------------------------------
+
+/**
+ * Sets the daylight savings starting rule. For example, in the U.S., Daylight Savings
+ * Time starts at the first Sunday in April, at 2 AM in standard time.
+ * Therefore, you can set the start rule by calling:
+ * setStartRule(TimeFields.APRIL, 1, TimeFields.SUNDAY, 2*60*60*1000);
+ * The dayOfWeekInMonth and dayOfWeek parameters together specify how to calculate
+ * the exact starting date.  Their exact meaning depend on their respective signs,
+ * allowing various types of rules to be constructed, as follows:<ul>
+ *   <li>If both dayOfWeekInMonth and dayOfWeek are positive, they specify the
+ *       day of week in the month (e.g., (2, WEDNESDAY) is the second Wednesday
+ *       of the month).
+ *   <li>If dayOfWeek is positive and dayOfWeekInMonth is negative, they specify
+ *       the day of week in the month counting backward from the end of the month.
+ *       (e.g., (-1, MONDAY) is the last Monday in the month)
+ *   <li>If dayOfWeek is zero and dayOfWeekInMonth is positive, dayOfWeekInMonth
+ *       specifies the day of the month, regardless of what day of the week it is.
+ *       (e.g., (10, 0) is the tenth day of the month)
+ *   <li>If dayOfWeek is zero and dayOfWeekInMonth is negative, dayOfWeekInMonth
+ *       specifies the day of the month counting backward from the end of the
+ *       month, regardless of what day of the week it is (e.g., (-2, 0) is the
+ *       next-to-last day of the month).
+ *   <li>If dayOfWeek is negative and dayOfWeekInMonth is positive, they specify the
+ *       first specified day of the week on or after the specfied day of the month.
+ *       (e.g., (15, -SUNDAY) is the first Sunday after the 15th of the month
+ *       [or the 15th itself if the 15th is a Sunday].)
+ *   <li>If dayOfWeek and DayOfWeekInMonth are both negative, they specify the
+ *       last specified day of the week on or before the specified day of the month.
+ *       (e.g., (-20, -TUESDAY) is the last Tuesday before the 20th of the month
+ *       [or the 20th itself if the 20th is a Tuesday].)</ul>
+ * @param month the daylight savings starting month. Month is 0-based.
+ * eg, 0 for January.
+ * @param dayOfWeekInMonth the daylight savings starting
+ * day-of-week-in-month. Please see the member description for an example.
+ * @param dayOfWeek the daylight savings starting day-of-week. Please see
+ * the member description for an example.
+ * @param time the daylight savings starting time. Please see the member
+ * description for an example.
+ */
+ 
+void
+SimpleTimeZone::setStartRule(int32_t month, int32_t dayOfWeekInMonth, int32_t dayOfWeek,
+                             int32_t time, TimeMode mode, UErrorCode& status)
+{
+    startMonth     = (int8_t)month;
+    startDay       = (int8_t)dayOfWeekInMonth;
+    startDayOfWeek = (int8_t)dayOfWeek;
+    startTime      = time;
+    startTimeMode  = mode;
+    decodeStartRule(status);
+    transitionRulesInitialized = FALSE;
+}
+
+// -------------------------------------
+
+void 
+SimpleTimeZone::setStartRule(int32_t month, int32_t dayOfMonth, 
+                             int32_t time, TimeMode mode, UErrorCode& status) 
+{
+    setStartRule(month, dayOfMonth, 0, time, mode, status);
+}
+
+// -------------------------------------
+
+void 
+SimpleTimeZone::setStartRule(int32_t month, int32_t dayOfMonth, int32_t dayOfWeek, 
+                             int32_t time, TimeMode mode, UBool after, UErrorCode& status)
+{
+    setStartRule(month, after ? dayOfMonth : -dayOfMonth,
+                 -dayOfWeek, time, mode, status);
+}
+
+// -------------------------------------
+
+/**
+ * Sets the daylight savings ending rule. For example, in the U.S., Daylight
+ * Savings Time ends at the last (-1) Sunday in October, at 2 AM in standard time.
+ * Therefore, you can set the end rule by calling:
+ * setEndRule(TimeFields.OCTOBER, -1, TimeFields.SUNDAY, 2*60*60*1000);
+ * Various other types of rules can be specified by manipulating the dayOfWeek
+ * and dayOfWeekInMonth parameters.  For complete details, see the documentation
+ * for setStartRule().
+ * @param month the daylight savings ending month. Month is 0-based.
+ * eg, 0 for January.
+ * @param dayOfWeekInMonth the daylight savings ending
+ * day-of-week-in-month. See setStartRule() for a complete explanation.
+ * @param dayOfWeek the daylight savings ending day-of-week. See setStartRule()
+ * for a complete explanation.
+ * @param time the daylight savings ending time. Please see the member
+ * description for an example.
+ */
+
+void
+SimpleTimeZone::setEndRule(int32_t month, int32_t dayOfWeekInMonth, int32_t dayOfWeek,
+                           int32_t time, TimeMode mode, UErrorCode& status)
+{
+    endMonth     = (int8_t)month;
+    endDay       = (int8_t)dayOfWeekInMonth;
+    endDayOfWeek = (int8_t)dayOfWeek;
+    endTime      = time;
+    endTimeMode  = mode;
+    decodeEndRule(status);
+    transitionRulesInitialized = FALSE;
+}
+
+// -------------------------------------
+
+void 
+SimpleTimeZone::setEndRule(int32_t month, int32_t dayOfMonth, 
+                           int32_t time, TimeMode mode, UErrorCode& status)
+{
+    setEndRule(month, dayOfMonth, 0, time, mode, status);
+}
+
+// -------------------------------------
+
+void 
+SimpleTimeZone::setEndRule(int32_t month, int32_t dayOfMonth, int32_t dayOfWeek, 
+                           int32_t time, TimeMode mode, UBool after, UErrorCode& status)
+{
+    setEndRule(month, after ? dayOfMonth : -dayOfMonth,
+               -dayOfWeek, time, mode, status);
+}
+
+// -------------------------------------
+
+int32_t
+SimpleTimeZone::getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
+                          uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const
+{
+    // Check the month before calling Grego::monthLength(). This
+    // duplicates the test that occurs in the 7-argument getOffset(),
+    // however, this is unavoidable. We don't mind because this method, in
+    // fact, should not be called; internal code should always call the
+    // 7-argument getOffset(), and outside code should use Calendar.get(int
+    // field) with fields ZONE_OFFSET and DST_OFFSET. We can't get rid of
+    // this method because it's public API. - liu 8/10/98
+    if(month < UCAL_JANUARY || month > UCAL_DECEMBER) {
+        status = U_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+
+    return getOffset(era, year, month, day, dayOfWeek, millis, Grego::monthLength(year, month), status);
+}
+
+int32_t 
+SimpleTimeZone::getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
+                          uint8_t dayOfWeek, int32_t millis, 
+                          int32_t /*monthLength*/, UErrorCode& status) const
+{
+    // Check the month before calling Grego::monthLength(). This
+    // duplicates a test that occurs in the 9-argument getOffset(),
+    // however, this is unavoidable. We don't mind because this method, in
+    // fact, should not be called; internal code should always call the
+    // 9-argument getOffset(), and outside code should use Calendar.get(int
+    // field) with fields ZONE_OFFSET and DST_OFFSET. We can't get rid of
+    // this method because it's public API. - liu 8/10/98
+    if (month < UCAL_JANUARY
+        || month > UCAL_DECEMBER) {
+        status = U_ILLEGAL_ARGUMENT_ERROR;
+        return -1;
+    }
+
+    // We ignore monthLength because it can be derived from year and month.
+    // This is so that February in leap years is calculated correctly.
+    // We keep this argument in this function for backwards compatibility.
+    return getOffset(era, year, month, day, dayOfWeek, millis,
+                     Grego::monthLength(year, month),
+                     Grego::previousMonthLength(year, month),
+                     status);
+}
+
+int32_t 
+SimpleTimeZone::getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
+                          uint8_t dayOfWeek, int32_t millis, 
+                          int32_t monthLength, int32_t prevMonthLength,
+                          UErrorCode& status) const
+{
+    if(U_FAILURE(status)) return 0;
+
+    if ((era != GregorianCalendar::AD && era != GregorianCalendar::BC)
+        || month < UCAL_JANUARY
+        || month > UCAL_DECEMBER
+        || day < 1
+        || day > monthLength
+        || dayOfWeek < UCAL_SUNDAY
+        || dayOfWeek > UCAL_SATURDAY
+        || millis < 0
+        || millis >= U_MILLIS_PER_DAY
+        || monthLength < 28
+        || monthLength > 31
+        || prevMonthLength < 28
+        || prevMonthLength > 31) {
+        status = U_ILLEGAL_ARGUMENT_ERROR;
+        return -1;
+    }
+
+    int32_t result = rawOffset;
+
+    // Bail out if we are before the onset of daylight savings time
+    if(!useDaylight || year < startYear || era != GregorianCalendar::AD) 
+        return result;
+
+    // Check for southern hemisphere.  We assume that the start and end
+    // month are different.
+    UBool southern = (startMonth > endMonth);
+
+    // Compare the date to the starting and ending rules.+1 = date>rule, -1
+    // = date<rule, 0 = date==rule.
+    int32_t startCompare = compareToRule((int8_t)month, (int8_t)monthLength, (int8_t)prevMonthLength,
+                                         (int8_t)day, (int8_t)dayOfWeek, millis,
+                                         startTimeMode == UTC_TIME ? -rawOffset : 0,
+                                         startMode, (int8_t)startMonth, (int8_t)startDayOfWeek,
+                                         (int8_t)startDay, startTime);
+    int32_t endCompare = 0;
+
+    /* We don't always have to compute endCompare.  For many instances,
+     * startCompare is enough to determine if we are in DST or not.  In the
+     * northern hemisphere, if we are before the start rule, we can't have
+     * DST.  In the southern hemisphere, if we are after the start rule, we
+     * must have DST.  This is reflected in the way the next if statement
+     * (not the one immediately following) short circuits. */
+    if(southern != (startCompare >= 0)) {
+        endCompare = compareToRule((int8_t)month, (int8_t)monthLength, (int8_t)prevMonthLength,
+                                   (int8_t)day, (int8_t)dayOfWeek, millis,
+                                   endTimeMode == WALL_TIME ? dstSavings :
+                                    (endTimeMode == UTC_TIME ? -rawOffset : 0),
+                                   endMode, (int8_t)endMonth, (int8_t)endDayOfWeek,
+                                   (int8_t)endDay, endTime);
+    }
+
+    // Check for both the northern and southern hemisphere cases.  We
+    // assume that in the northern hemisphere, the start rule is before the
+    // end rule within the calendar year, and vice versa for the southern
+    // hemisphere.
+    if ((!southern && (startCompare >= 0 && endCompare < 0)) ||
+        (southern && (startCompare >= 0 || endCompare < 0)))
+        result += dstSavings;
+
+    return result;
+}
+
+void
+SimpleTimeZone::getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt,
+                                   int32_t& rawOffsetGMT, int32_t& savingsDST, UErrorCode& status) /*const*/ {
+    if (U_FAILURE(status)) {
+        return;
+    }
+
+    rawOffsetGMT = getRawOffset();
+    int32_t year, month, dom, dow;
+    double day = uprv_floor(date / U_MILLIS_PER_DAY);
+    int32_t millis = (int32_t) (date - day * U_MILLIS_PER_DAY);
+
+    Grego::dayToFields(day, year, month, dom, dow);
+
+    savingsDST = getOffset(GregorianCalendar::AD, year, month, dom,
+                          (uint8_t) dow, millis,
+                          Grego::monthLength(year, month),
+                          status) - rawOffsetGMT;
+    if (U_FAILURE(status)) {
+        return;
+    }
+
+    UBool recalc = FALSE;
+
+    // Now we need some adjustment
+    if (savingsDST > 0) {
+        if ((nonExistingTimeOpt & kStdDstMask) == kStandard
+            || ((nonExistingTimeOpt & kStdDstMask) != kDaylight && (nonExistingTimeOpt & kFormerLatterMask) != kLatter)) {
+            date -= getDSTSavings();
+            recalc = TRUE;
+        }
+    } else {
+        if ((duplicatedTimeOpt & kStdDstMask) == kDaylight
+                || ((duplicatedTimeOpt & kStdDstMask) != kStandard && (duplicatedTimeOpt & kFormerLatterMask) == kFormer)) {
+            date -= getDSTSavings();
+            recalc = TRUE;
+        }
+    }
+    if (recalc) {
+        day = uprv_floor(date / U_MILLIS_PER_DAY);
+        millis = (int32_t) (date - day * U_MILLIS_PER_DAY);
+        Grego::dayToFields(day, year, month, dom, dow);
+        savingsDST = getOffset(GregorianCalendar::AD, year, month, dom,
+                          (uint8_t) dow, millis,
+                          Grego::monthLength(year, month),
+                          status) - rawOffsetGMT;
+    }
+}
+
+// -------------------------------------
+
+/**
+ * Compare a given date in the year to a rule. Return 1, 0, or -1, depending
+ * on whether the date is after, equal to, or before the rule date. The
+ * millis are compared directly against the ruleMillis, so any
+ * standard-daylight adjustments must be handled by the caller.
+ *
+ * @return  1 if the date is after the rule date, -1 if the date is before
+ *          the rule date, or 0 if the date is equal to the rule date.
+ */
+int32_t 
+SimpleTimeZone::compareToRule(int8_t month, int8_t monthLen, int8_t prevMonthLen,
+                              int8_t dayOfMonth,
+                              int8_t dayOfWeek, int32_t millis, int32_t millisDelta,
+                              EMode ruleMode, int8_t ruleMonth, int8_t ruleDayOfWeek,
+                              int8_t ruleDay, int32_t ruleMillis)
+{
+    // Make adjustments for startTimeMode and endTimeMode
+    millis += millisDelta;
+    while (millis >= U_MILLIS_PER_DAY) {
+        millis -= U_MILLIS_PER_DAY;
+        ++dayOfMonth;
+        dayOfWeek = (int8_t)(1 + (dayOfWeek % 7)); // dayOfWeek is one-based
+        if (dayOfMonth > monthLen) {
+            dayOfMonth = 1;
+            /* When incrementing the month, it is desirible to overflow
+             * from DECEMBER to DECEMBER+1, since we use the result to
+             * compare against a real month. Wraparound of the value
+             * leads to bug 4173604. */
+            ++month;
+        }
+    }
+    while (millis < 0) {
+        millis += U_MILLIS_PER_DAY;
+        --dayOfMonth;
+        dayOfWeek = (int8_t)(1 + ((dayOfWeek+5) % 7)); // dayOfWeek is one-based
+        if (dayOfMonth < 1) {
+            dayOfMonth = prevMonthLen;
+            --month;
+        }
+    }
+
+    // first compare months.  If they're different, we don't have to worry about days
+    // and times
+    if (month < ruleMonth) return -1;
+    else if (month > ruleMonth) return 1;
+
+    // calculate the actual day of month for the rule
+    int32_t ruleDayOfMonth = 0;
+
+    // Adjust the ruleDay to the monthLen, for non-leap year February 29 rule days.
+    if (ruleDay > monthLen) {
+        ruleDay = monthLen;
+    }
+
+    switch (ruleMode)
+    {
+    // if the mode is day-of-month, the day of month is given
+    case DOM_MODE:
+        ruleDayOfMonth = ruleDay;
+        break;
+
+    // if the mode is day-of-week-in-month, calculate the day-of-month from it
+    case DOW_IN_MONTH_MODE:
+        // In this case ruleDay is the day-of-week-in-month (this code is using
+        // the dayOfWeek and dayOfMonth parameters to figure out the day-of-week
+        // of the first day of the month, so it's trusting that they're really
+        // consistent with each other)
+        if (ruleDay > 0)
+            ruleDayOfMonth = 1 + (ruleDay - 1) * 7 +
+                (7 + ruleDayOfWeek - (dayOfWeek - dayOfMonth + 1)) % 7;
+        
+        // if ruleDay is negative (we assume it's not zero here), we have to do
+        // the same calculation figuring backward from the last day of the month.
+        else
+        {
+            // (again, this code is trusting that dayOfWeek and dayOfMonth are
+            // consistent with each other here, since we're using them to figure
+            // the day of week of the first of the month)
+            ruleDayOfMonth = monthLen + (ruleDay + 1) * 7 -
+                (7 + (dayOfWeek + monthLen - dayOfMonth) - ruleDayOfWeek) % 7;
+        }
+        break;
+
+    case DOW_GE_DOM_MODE:
+        ruleDayOfMonth = ruleDay +
+            (49 + ruleDayOfWeek - ruleDay - dayOfWeek + dayOfMonth) % 7;
+        break;
+
+    case DOW_LE_DOM_MODE:
+        ruleDayOfMonth = ruleDay -
+            (49 - ruleDayOfWeek + ruleDay + dayOfWeek - dayOfMonth) % 7;
+        // Note at this point ruleDayOfMonth may be <1, although it will
+        // be >=1 for well-formed rules.
+        break;
+    }
+
+    // now that we have a real day-in-month for the rule, we can compare days...
+    if (dayOfMonth < ruleDayOfMonth) return -1;
+    else if (dayOfMonth > ruleDayOfMonth) return 1;
+
+    // ...and if they're equal, we compare times
+    if (millis < ruleMillis) return -1;
+    else if (millis > ruleMillis) return 1;
+    else return 0;
+}
+
+// -------------------------------------
+
+int32_t
+SimpleTimeZone::getRawOffset() const
+{
+    return rawOffset;
+}
+
+// -------------------------------------
+
+void
+SimpleTimeZone::setRawOffset(int32_t offsetMillis)
+{
+    rawOffset = offsetMillis;
+    transitionRulesInitialized = FALSE;
+}
+
+// -------------------------------------
+
+void 
+SimpleTimeZone::setDSTSavings(int32_t millisSavedDuringDST, UErrorCode& status) 
+{
+    if (millisSavedDuringDST <= 0) {
+        status = U_ILLEGAL_ARGUMENT_ERROR;
+    }
+    else {
+        dstSavings = millisSavedDuringDST;
+    }
+    transitionRulesInitialized = FALSE;
+}
+
+// -------------------------------------
+
+int32_t 
+SimpleTimeZone::getDSTSavings() const
+{
+    return dstSavings;
+}
+
+// -------------------------------------
+
+UBool
+SimpleTimeZone::useDaylightTime() const
+{
+    return useDaylight;
+}
+
+// -------------------------------------
+
+/**
+ * Overrides TimeZone
+ * Queries if the given date is in Daylight Savings Time.
+ */
+UBool SimpleTimeZone::inDaylightTime(UDate date, UErrorCode& status) const
+{
+    // This method is wasteful since it creates a new GregorianCalendar and
+    // deletes it each time it is called.  However, this is a deprecated method
+    // and provided only for Java compatibility as of 8/6/97 [LIU].
+    if (U_FAILURE(status)) return FALSE;
+    GregorianCalendar *gc = new GregorianCalendar(*this, status);
+    /* test for NULL */
+    if (gc == 0) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+        return FALSE;
+    }
+    gc->setTime(date, status);
+    UBool result = gc->inDaylightTime(status);
+    delete gc;
+    return result;
+}
+
+// -------------------------------------
+
+/**
+ * Return true if this zone has the same rules and offset as another zone.
+ * @param other the TimeZone object to be compared with
+ * @return true if the given zone has the same rules and offset as this one
+ */
+UBool 
+SimpleTimeZone::hasSameRules(const TimeZone& other) const
+{
+    if (this == &other) return TRUE;
+    if (typeid(*this) != typeid(other)) return FALSE;
+    SimpleTimeZone *that = (SimpleTimeZone*)&other;
+    return rawOffset     == that->rawOffset &&
+        useDaylight     == that->useDaylight &&
+        (!useDaylight
+         // Only check rules if using DST
+         || (dstSavings     == that->dstSavings &&
+             startMode      == that->startMode &&
+             startMonth     == that->startMonth &&
+             startDay       == that->startDay &&
+             startDayOfWeek == that->startDayOfWeek &&
+             startTime      == that->startTime &&
+             startTimeMode  == that->startTimeMode &&
+             endMode        == that->endMode &&
+             endMonth       == that->endMonth &&
+             endDay         == that->endDay &&
+             endDayOfWeek   == that->endDayOfWeek &&
+             endTime        == that->endTime &&
+             endTimeMode    == that->endTimeMode &&
+             startYear      == that->startYear));
+}
+
+// -------------------------------------
+
+//----------------------------------------------------------------------
+// Rule representation
+//
+// We represent the following flavors of rules:
+//       5        the fifth of the month
+//       lastSun  the last Sunday in the month
+//       lastMon  the last Monday in the month
+//       Sun>=8   first Sunday on or after the eighth
+//       Sun<=25  last Sunday on or before the 25th
+// This is further complicated by the fact that we need to remain
+// backward compatible with the 1.1 FCS.  Finally, we need to minimize
+// API changes.  In order to satisfy these requirements, we support
+// three representation systems, and we translate between them.
+//
+// INTERNAL REPRESENTATION
+// This is the format SimpleTimeZone objects take after construction or
+// streaming in is complete.  Rules are represented directly, using an
+// unencoded format.  We will discuss the start rule only below; the end
+// rule is analogous.
+//   startMode      Takes on enumerated values DAY_OF_MONTH,
+//                  DOW_IN_MONTH, DOW_AFTER_DOM, or DOW_BEFORE_DOM.
+//   startDay       The day of the month, or for DOW_IN_MONTH mode, a
+//                  value indicating which DOW, such as +1 for first,
+//                  +2 for second, -1 for last, etc.
+//   startDayOfWeek The day of the week.  Ignored for DAY_OF_MONTH.
+//
+// ENCODED REPRESENTATION
+// This is the format accepted by the constructor and by setStartRule()
+// and setEndRule().  It uses various combinations of positive, negative,
+// and zero values to encode the different rules.  This representation
+// allows us to specify all the different rule flavors without altering
+// the API.
+//   MODE              startMonth    startDay    startDayOfWeek
+//   DOW_IN_MONTH_MODE >=0           !=0         >0
+//   DOM_MODE          >=0           >0          ==0
+//   DOW_GE_DOM_MODE   >=0           >0          <0
+//   DOW_LE_DOM_MODE   >=0           <0          <0
+//   (no DST)          don't care    ==0         don't care
+//
+// STREAMED REPRESENTATION
+// We must retain binary compatibility with the 1.1 FCS.  The 1.1 code only
+// handles DOW_IN_MONTH_MODE and non-DST mode, the latter indicated by the
+// flag useDaylight.  When we stream an object out, we translate into an
+// approximate DOW_IN_MONTH_MODE representation so the object can be parsed
+// and used by 1.1 code.  Following that, we write out the full
+// representation separately so that contemporary code can recognize and
+// parse it.  The full representation is written in a "packed" format,
+// consisting of a version number, a length, and an array of bytes.  Future
+// versions of this class may specify different versions.  If they wish to
+// include additional data, they should do so by storing them after the
+// packed representation below.
+//----------------------------------------------------------------------
+
+/**
+ * Given a set of encoded rules in startDay and startDayOfMonth, decode
+ * them and set the startMode appropriately.  Do the same for endDay and
+ * endDayOfMonth.  Upon entry, the day of week variables may be zero or
+ * negative, in order to indicate special modes.  The day of month
+ * variables may also be negative.  Upon exit, the mode variables will be
+ * set, and the day of week and day of month variables will be positive.
+ * This method also recognizes a startDay or endDay of zero as indicating
+ * no DST.
+ */
+void 
+SimpleTimeZone::decodeRules(UErrorCode& status)
+{
+    decodeStartRule(status);
+    decodeEndRule(status);
+}
+
+/**
+ * Decode the start rule and validate the parameters.  The parameters are
+ * expected to be in encoded form, which represents the various rule modes
+ * by negating or zeroing certain values.  Representation formats are:
+ * <p>
+ * <pre>
+ *            DOW_IN_MONTH  DOM    DOW>=DOM  DOW<=DOM  no DST
+ *            ------------  -----  --------  --------  ----------
+ * month       0..11        same    same      same     don't care
+ * day        -5..5         1..31   1..31    -1..-31   0
+ * dayOfWeek   1..7         0      -1..-7    -1..-7    don't care
+ * time        0..ONEDAY    same    same      same     don't care
+ * </pre>
+ * The range for month does not include UNDECIMBER since this class is
+ * really specific to GregorianCalendar, which does not use that month.
+ * The range for time includes ONEDAY (vs. ending at ONEDAY-1) because the
+ * end rule is an exclusive limit point.  That is, the range of times that
+ * are in DST include those >= the start and < the end.  For this reason,
+ * it should be possible to specify an end of ONEDAY in order to include the
+ * entire day.  Although this is equivalent to time 0 of the following day,
+ * it's not always possible to specify that, for example, on December 31.
+ * While arguably the start range should still be 0..ONEDAY-1, we keep
+ * the start and end ranges the same for consistency.
+ */
+void 
+SimpleTimeZone::decodeStartRule(UErrorCode& status) 
+{
+    if(U_FAILURE(status)) return;
+
+    useDaylight = (UBool)((startDay != 0) && (endDay != 0) ? TRUE : FALSE);
+    if (useDaylight && dstSavings == 0) {
+        dstSavings = U_MILLIS_PER_HOUR;
+    }
+    if (startDay != 0) {
+        if (startMonth < UCAL_JANUARY || startMonth > UCAL_DECEMBER) {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+        if (startTime < 0 || startTime > U_MILLIS_PER_DAY ||
+            startTimeMode < WALL_TIME || startTimeMode > UTC_TIME) {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+        if (startDayOfWeek == 0) {
+            startMode = DOM_MODE;
+        } else {
+            if (startDayOfWeek > 0) {
+                startMode = DOW_IN_MONTH_MODE;
+            } else {
+                startDayOfWeek = (int8_t)-startDayOfWeek;
+                if (startDay > 0) {
+                    startMode = DOW_GE_DOM_MODE;
+                } else {
+                    startDay = (int8_t)-startDay;
+                    startMode = DOW_LE_DOM_MODE;
+                }
+            }
+            if (startDayOfWeek > UCAL_SATURDAY) {
+                status = U_ILLEGAL_ARGUMENT_ERROR;
+                return;
+            }
+        }
+        if (startMode == DOW_IN_MONTH_MODE) {
+            if (startDay < -5 || startDay > 5) {
+                status = U_ILLEGAL_ARGUMENT_ERROR;
+                return;
+            }
+        } else if (startDay<1 || startDay > STATICMONTHLENGTH[startMonth]) {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+    }
+}
+
+/**
+ * Decode the end rule and validate the parameters.  This method is exactly
+ * analogous to decodeStartRule().
+ * @see decodeStartRule
+ */
+void 
+SimpleTimeZone::decodeEndRule(UErrorCode& status) 
+{
+    if(U_FAILURE(status)) return;
+
+    useDaylight = (UBool)((startDay != 0) && (endDay != 0) ? TRUE : FALSE);
+    if (useDaylight && dstSavings == 0) {
+        dstSavings = U_MILLIS_PER_HOUR;
+    }
+    if (endDay != 0) {
+        if (endMonth < UCAL_JANUARY || endMonth > UCAL_DECEMBER) {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+        if (endTime < 0 || endTime > U_MILLIS_PER_DAY ||
+            endTimeMode < WALL_TIME || endTimeMode > UTC_TIME) {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+        if (endDayOfWeek == 0) {
+            endMode = DOM_MODE;
+        } else {
+            if (endDayOfWeek > 0) {
+                endMode = DOW_IN_MONTH_MODE;
+            } else {
+                endDayOfWeek = (int8_t)-endDayOfWeek;
+                if (endDay > 0) {
+                    endMode = DOW_GE_DOM_MODE;
+                } else {
+                    endDay = (int8_t)-endDay;
+                    endMode = DOW_LE_DOM_MODE;
+                }
+            }
+            if (endDayOfWeek > UCAL_SATURDAY) {
+                status = U_ILLEGAL_ARGUMENT_ERROR;
+                return;
+            }
+        }
+        if (endMode == DOW_IN_MONTH_MODE) {
+            if (endDay < -5 || endDay > 5) {
+                status = U_ILLEGAL_ARGUMENT_ERROR;
+                return;
+            }
+        } else if (endDay<1 || endDay > STATICMONTHLENGTH[endMonth]) {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+    }
+}
+
+UBool
+SimpleTimeZone::getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) /*const*/ {
+    if (!useDaylight) {
+        return FALSE;
+    }
+
+    UErrorCode status = U_ZERO_ERROR;
+    initTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return FALSE;
+    }
+
+    UDate firstTransitionTime = firstTransition->getTime();
+    if (base < firstTransitionTime || (inclusive && base == firstTransitionTime)) {
+        result = *firstTransition;
+    }
+    UDate stdDate, dstDate;
+    UBool stdAvail = stdRule->getNextStart(base, dstRule->getRawOffset(), dstRule->getDSTSavings(), inclusive, stdDate);
+    UBool dstAvail = dstRule->getNextStart(base, stdRule->getRawOffset(), stdRule->getDSTSavings(), inclusive, dstDate);
+    if (stdAvail && (!dstAvail || stdDate < dstDate)) {
+        result.setTime(stdDate);
+        result.setFrom((const TimeZoneRule&)*dstRule);
+        result.setTo((const TimeZoneRule&)*stdRule);
+        return TRUE;
+    }
+    if (dstAvail && (!stdAvail || dstDate < stdDate)) {
+        result.setTime(dstDate);
+        result.setFrom((const TimeZoneRule&)*stdRule);
+        result.setTo((const TimeZoneRule&)*dstRule);
+        return TRUE;
+    }
+    return FALSE;
+}
+
+UBool
+SimpleTimeZone::getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) /*const*/ {
+    if (!useDaylight) {
+        return FALSE;
+    }
+
+    UErrorCode status = U_ZERO_ERROR;
+    initTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return FALSE;
+    }
+
+    UDate firstTransitionTime = firstTransition->getTime();
+    if (base < firstTransitionTime || (!inclusive && base == firstTransitionTime)) {
+        return FALSE;
+    }
+    UDate stdDate, dstDate;
+    UBool stdAvail = stdRule->getPreviousStart(base, dstRule->getRawOffset(), dstRule->getDSTSavings(), inclusive, stdDate);
+    UBool dstAvail = dstRule->getPreviousStart(base, stdRule->getRawOffset(), stdRule->getDSTSavings(), inclusive, dstDate);
+    if (stdAvail && (!dstAvail || stdDate > dstDate)) {
+        result.setTime(stdDate);
+        result.setFrom((const TimeZoneRule&)*dstRule);
+        result.setTo((const TimeZoneRule&)*stdRule);
+        return TRUE;
+    }
+    if (dstAvail && (!stdAvail || dstDate > stdDate)) {
+        result.setTime(dstDate);
+        result.setFrom((const TimeZoneRule&)*stdRule);
+        result.setTo((const TimeZoneRule&)*dstRule);
+        return TRUE;
+    }
+    return FALSE;
+}
+
+void
+SimpleTimeZone::clearTransitionRules(void) {
+    initialRule = NULL;
+    firstTransition = NULL;
+    stdRule = NULL;
+    dstRule = NULL;
+    transitionRulesInitialized = FALSE;
+}
+
+void
+SimpleTimeZone::deleteTransitionRules(void) {
+    if (initialRule != NULL) {
+        delete initialRule;
+    }
+    if (firstTransition != NULL) {
+        delete firstTransition;
+    }
+    if (stdRule != NULL) {
+        delete stdRule;
+    }
+    if (dstRule != NULL) {
+        delete dstRule;
+    }
+    clearTransitionRules();
+ }
+
+void
+SimpleTimeZone::initTransitionRules(UErrorCode& status) {
+    if (U_FAILURE(status)) {
+        return;
+    }
+    if (transitionRulesInitialized) {
+        return;
+    }
+    deleteTransitionRules();
+    UnicodeString tzid;
+    getID(tzid);
+
+    if (useDaylight) {
+        DateTimeRule* dtRule;
+        DateTimeRule::TimeRuleType timeRuleType;
+        UDate firstStdStart, firstDstStart;
+
+        // Create a TimeZoneRule for daylight saving time
+        timeRuleType = (startTimeMode == STANDARD_TIME) ? DateTimeRule::STANDARD_TIME :
+            ((startTimeMode == UTC_TIME) ? DateTimeRule::UTC_TIME : DateTimeRule::WALL_TIME);
+        switch (startMode) {
+        case DOM_MODE:
+            dtRule = new DateTimeRule(startMonth, startDay, startTime, timeRuleType);
+            break;
+        case DOW_IN_MONTH_MODE:
+            dtRule = new DateTimeRule(startMonth, startDay, startDayOfWeek, startTime, timeRuleType);
+            break;
+        case DOW_GE_DOM_MODE:
+            dtRule = new DateTimeRule(startMonth, startDay, startDayOfWeek, true, startTime, timeRuleType);
+            break;
+        case DOW_LE_DOM_MODE:
+            dtRule = new DateTimeRule(startMonth, startDay, startDayOfWeek, false, startTime, timeRuleType);
+            break;
+        default:
+            status = U_INVALID_STATE_ERROR;
+            return;
+        }
+        // Check for Null pointer
+        if (dtRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                return;
+        }
+        // For now, use ID + "(DST)" as the name
+        dstRule = new AnnualTimeZoneRule(tzid+DST_STR, getRawOffset(), getDSTSavings(),
+            dtRule, startYear, AnnualTimeZoneRule::MAX_YEAR);
+        
+        // Check for Null pointer
+        if (dstRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+        }
+ 
+        // Calculate the first DST start time
+        dstRule->getFirstStart(getRawOffset(), 0, firstDstStart);
+
+        // Create a TimeZoneRule for standard time
+        timeRuleType = (endTimeMode == STANDARD_TIME) ? DateTimeRule::STANDARD_TIME :
+            ((endTimeMode == UTC_TIME) ? DateTimeRule::UTC_TIME : DateTimeRule::WALL_TIME);
+        switch (endMode) {
+        case DOM_MODE:
+            dtRule = new DateTimeRule(endMonth, endDay, endTime, timeRuleType);
+            break;
+        case DOW_IN_MONTH_MODE:
+            dtRule = new DateTimeRule(endMonth, endDay, endDayOfWeek, endTime, timeRuleType);
+            break;
+        case DOW_GE_DOM_MODE:
+            dtRule = new DateTimeRule(endMonth, endDay, endDayOfWeek, true, endTime, timeRuleType);
+            break;
+        case DOW_LE_DOM_MODE:
+            dtRule = new DateTimeRule(endMonth, endDay, endDayOfWeek, false, endTime, timeRuleType);
+            break;
+        }
+        
+        // Check for Null pointer
+        if (dtRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+        }
+        // For now, use ID + "(STD)" as the name
+        stdRule = new AnnualTimeZoneRule(tzid+STD_STR, getRawOffset(), 0,
+            dtRule, startYear, AnnualTimeZoneRule::MAX_YEAR);
+        
+        //Check for Null pointer
+        if (stdRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+        }
+
+        // Calculate the first STD start time
+        stdRule->getFirstStart(getRawOffset(), dstRule->getDSTSavings(), firstStdStart);
+
+        // Create a TimeZoneRule for initial time
+        if (firstStdStart < firstDstStart) {
+            initialRule = new InitialTimeZoneRule(tzid+DST_STR, getRawOffset(), dstRule->getDSTSavings());
+            firstTransition = new TimeZoneTransition(firstStdStart, *initialRule, *stdRule);
+        } else {
+            initialRule = new InitialTimeZoneRule(tzid+STD_STR, getRawOffset(), 0);
+            firstTransition = new TimeZoneTransition(firstDstStart, *initialRule, *dstRule);
+        }
+        // Check for null pointers.
+        if (initialRule == NULL || firstTransition == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+        }
+        
+    } else {
+        // Create a TimeZoneRule for initial time
+        initialRule = new InitialTimeZoneRule(tzid, getRawOffset(), 0);
+        // Check for null pointer.
+        if (initialRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+        }
+    }
+
+    transitionRulesInitialized = true;
+}
+
+int32_t
+SimpleTimeZone::countTransitionRules(UErrorCode& /*status*/) /*const*/ {
+    return (useDaylight) ? 2 : 0;
+}
+
+void
+SimpleTimeZone::getTimeZoneRules(const InitialTimeZoneRule*& initial,
+                                 const TimeZoneRule* trsrules[],
+                                 int32_t& trscount,
+                                 UErrorCode& status) /*const*/ {
+    if (U_FAILURE(status)) {
+        return;
+    }
+    initTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return;
+    }
+    initial = initialRule;
+    int32_t cnt = 0;
+    if (stdRule != NULL) {
+        if (cnt < trscount) {
+            trsrules[cnt++] = stdRule;
+        }
+        if (cnt < trscount) {
+            trsrules[cnt++] = dstRule;
+        }
+    }
+    trscount = cnt;
+}
+
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_FORMATTING */
+
+//eof