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Diffstat (limited to 'src/mscorlib/corefx/System/Globalization/GregorianCalendarHelper.cs')
| -rw-r--r-- | src/mscorlib/corefx/System/Globalization/GregorianCalendarHelper.cs | 668 |
1 files changed, 668 insertions, 0 deletions
diff --git a/src/mscorlib/corefx/System/Globalization/GregorianCalendarHelper.cs b/src/mscorlib/corefx/System/Globalization/GregorianCalendarHelper.cs new file mode 100644 index 0000000000..f595e72d0d --- /dev/null +++ b/src/mscorlib/corefx/System/Globalization/GregorianCalendarHelper.cs @@ -0,0 +1,668 @@ +// Licensed to the .NET Foundation under one or more agreements. +// The .NET Foundation licenses this file to you under the MIT license. +// See the LICENSE file in the project root for more information. + +using System; +using System.Diagnostics.Contracts; +using System.Runtime.Serialization; +using System.Threading; + +namespace System.Globalization +{ + // Gregorian Calendars use Era Info + [Serializable] + internal class EraInfo + { + internal int era; // The value of the era. + internal long ticks; // The time in ticks when the era starts + internal int yearOffset; // The offset to Gregorian year when the era starts. + // Gregorian Year = Era Year + yearOffset + // Era Year = Gregorian Year - yearOffset + internal int minEraYear; // Min year value in this era. Generally, this value is 1, but this may + // be affected by the DateTime.MinValue; + internal int maxEraYear; // Max year value in this era. (== the year length of the era + 1) + + [OptionalField(VersionAdded = 4)] + internal String eraName; // The era name + [OptionalField(VersionAdded = 4)] + internal String abbrevEraName; // Abbreviated Era Name + [OptionalField(VersionAdded = 4)] + internal String englishEraName; // English era name + + internal EraInfo(int era, int startYear, int startMonth, int startDay, int yearOffset, int minEraYear, int maxEraYear) + { + this.era = era; + this.yearOffset = yearOffset; + this.minEraYear = minEraYear; + this.maxEraYear = maxEraYear; + this.ticks = new DateTime(startYear, startMonth, startDay).Ticks; + } + + internal EraInfo(int era, int startYear, int startMonth, int startDay, int yearOffset, int minEraYear, int maxEraYear, + String eraName, String abbrevEraName, String englishEraName) + { + this.era = era; + this.yearOffset = yearOffset; + this.minEraYear = minEraYear; + this.maxEraYear = maxEraYear; + this.ticks = new DateTime(startYear, startMonth, startDay).Ticks; + this.eraName = eraName; + this.abbrevEraName = abbrevEraName; + this.englishEraName = englishEraName; + } + } + + // This calendar recognizes two era values: + // 0 CurrentEra (AD) + // 1 BeforeCurrentEra (BC) + [Serializable] + internal class GregorianCalendarHelper + { + // 1 tick = 100ns = 10E-7 second + // Number of ticks per time unit + internal const long TicksPerMillisecond = 10000; + internal const long TicksPerSecond = TicksPerMillisecond * 1000; + internal const long TicksPerMinute = TicksPerSecond * 60; + internal const long TicksPerHour = TicksPerMinute * 60; + internal const long TicksPerDay = TicksPerHour * 24; + + // Number of milliseconds per time unit + internal const int MillisPerSecond = 1000; + internal const int MillisPerMinute = MillisPerSecond * 60; + internal const int MillisPerHour = MillisPerMinute * 60; + internal const int MillisPerDay = MillisPerHour * 24; + + // Number of days in a non-leap year + internal const int DaysPerYear = 365; + // Number of days in 4 years + internal const int DaysPer4Years = DaysPerYear * 4 + 1; + // Number of days in 100 years + internal const int DaysPer100Years = DaysPer4Years * 25 - 1; + // Number of days in 400 years + internal const int DaysPer400Years = DaysPer100Years * 4 + 1; + + // Number of days from 1/1/0001 to 1/1/10000 + internal const int DaysTo10000 = DaysPer400Years * 25 - 366; + + internal const long MaxMillis = (long)DaysTo10000 * MillisPerDay; + + internal const int DatePartYear = 0; + internal const int DatePartDayOfYear = 1; + internal const int DatePartMonth = 2; + internal const int DatePartDay = 3; + + // + // This is the max Gregorian year can be represented by DateTime class. The limitation + // is derived from DateTime class. + // + internal int MaxYear + { + get + { + return (m_maxYear); + } + } + + internal static readonly int[] DaysToMonth365 = + { + 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 + }; + + internal static readonly int[] DaysToMonth366 = + { + 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 + }; + + [OptionalField(VersionAdded = 1)] + internal int m_maxYear = 9999; + [OptionalField(VersionAdded = 1)] + internal int m_minYear; + internal Calendar m_Cal; + + [OptionalField(VersionAdded = 1)] + internal EraInfo[] m_EraInfo; + [OptionalField(VersionAdded = 1)] + internal int[] m_eras = null; + + + // Construct an instance of gregorian calendar. + internal GregorianCalendarHelper(Calendar cal, EraInfo[] eraInfo) + { + m_Cal = cal; + m_EraInfo = eraInfo; + m_maxYear = m_EraInfo[0].maxEraYear; + m_minYear = m_EraInfo[0].minEraYear; ; + } + + /*=================================GetGregorianYear========================== + **Action: Get the Gregorian year value for the specified year in an era. + **Returns: The Gregorian year value. + **Arguments: + ** year the year value in Japanese calendar + ** era the Japanese emperor era value. + **Exceptions: + ** ArgumentOutOfRangeException if year value is invalid or era value is invalid. + ============================================================================*/ + + internal int GetGregorianYear(int year, int era) + { + if (year < 0) + { + throw new ArgumentOutOfRangeException("year", + SR.ArgumentOutOfRange_NeedNonNegNum); + } + Contract.EndContractBlock(); + + if (era == Calendar.CurrentEra) + { + era = m_Cal.CurrentEraValue; + } + + for (int i = 0; i < m_EraInfo.Length; i++) + { + if (era == m_EraInfo[i].era) + { + if (year < m_EraInfo[i].minEraYear || year > m_EraInfo[i].maxEraYear) + { + throw new ArgumentOutOfRangeException( + "year", + String.Format( + CultureInfo.CurrentCulture, + SR.ArgumentOutOfRange_Range, + m_EraInfo[i].minEraYear, + m_EraInfo[i].maxEraYear)); + } + return (m_EraInfo[i].yearOffset + year); + } + } + throw new ArgumentOutOfRangeException("era", SR.ArgumentOutOfRange_InvalidEraValue); + } + + internal bool IsValidYear(int year, int era) + { + if (year < 0) + { + return false; + } + + if (era == Calendar.CurrentEra) + { + era = m_Cal.CurrentEraValue; + } + + for (int i = 0; i < m_EraInfo.Length; i++) + { + if (era == m_EraInfo[i].era) + { + if (year < m_EraInfo[i].minEraYear || year > m_EraInfo[i].maxEraYear) + { + return false; + } + return true; + } + } + return false; + } + + + // Returns a given date part of this DateTime. This method is used + // to compute the year, day-of-year, month, or day part. + internal virtual int GetDatePart(long ticks, int part) + { + CheckTicksRange(ticks); + // n = number of days since 1/1/0001 + int n = (int)(ticks / TicksPerDay); + // y400 = number of whole 400-year periods since 1/1/0001 + int y400 = n / DaysPer400Years; + // n = day number within 400-year period + n -= y400 * DaysPer400Years; + // y100 = number of whole 100-year periods within 400-year period + int y100 = n / DaysPer100Years; + // Last 100-year period has an extra day, so decrement result if 4 + if (y100 == 4) y100 = 3; + // n = day number within 100-year period + n -= y100 * DaysPer100Years; + // y4 = number of whole 4-year periods within 100-year period + int y4 = n / DaysPer4Years; + // n = day number within 4-year period + n -= y4 * DaysPer4Years; + // y1 = number of whole years within 4-year period + int y1 = n / DaysPerYear; + // Last year has an extra day, so decrement result if 4 + if (y1 == 4) y1 = 3; + // If year was requested, compute and return it + if (part == DatePartYear) + { + return (y400 * 400 + y100 * 100 + y4 * 4 + y1 + 1); + } + // n = day number within year + n -= y1 * DaysPerYear; + // If day-of-year was requested, return it + if (part == DatePartDayOfYear) + { + return (n + 1); + } + // Leap year calculation looks different from IsLeapYear since y1, y4, + // and y100 are relative to year 1, not year 0 + bool leapYear = (y1 == 3 && (y4 != 24 || y100 == 3)); + int[] days = leapYear ? DaysToMonth366 : DaysToMonth365; + // All months have less than 32 days, so n >> 5 is a good conservative + // estimate for the month + int m = n >> 5 + 1; + // m = 1-based month number + while (n >= days[m]) m++; + // If month was requested, return it + if (part == DatePartMonth) return (m); + // Return 1-based day-of-month + return (n - days[m - 1] + 1); + } + + /*=================================GetAbsoluteDate========================== + **Action: Gets the absolute date for the given Gregorian date. The absolute date means + ** the number of days from January 1st, 1 A.D. + **Returns: the absolute date + **Arguments: + ** year the Gregorian year + ** month the Gregorian month + ** day the day + **Exceptions: + ** ArgumentOutOfRangException if year, month, day value is valid. + **Note: + ** This is an internal method used by DateToTicks() and the calculations of Hijri and Hebrew calendars. + ** Number of Days in Prior Years (both common and leap years) + + ** Number of Days in Prior Months of Current Year + + ** Number of Days in Current Month + ** + ============================================================================*/ + + internal static long GetAbsoluteDate(int year, int month, int day) + { + if (year >= 1 && year <= 9999 && month >= 1 && month <= 12) + { + int[] days = ((year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))) ? DaysToMonth366 : DaysToMonth365; + if (day >= 1 && (day <= days[month] - days[month - 1])) + { + int y = year - 1; + int absoluteDate = y * 365 + y / 4 - y / 100 + y / 400 + days[month - 1] + day - 1; + return (absoluteDate); + } + } + throw new ArgumentOutOfRangeException(null, SR.ArgumentOutOfRange_BadYearMonthDay); + } + + // Returns the tick count corresponding to the given year, month, and day. + // Will check the if the parameters are valid. + internal static long DateToTicks(int year, int month, int day) + { + return (GetAbsoluteDate(year, month, day) * TicksPerDay); + } + + // Return the tick count corresponding to the given hour, minute, second. + // Will check the if the parameters are valid. + internal static long TimeToTicks(int hour, int minute, int second, int millisecond) + { + //TimeSpan.TimeToTicks is a family access function which does no error checking, so + //we need to put some error checking out here. + if (hour >= 0 && hour < 24 && minute >= 0 && minute < 60 && second >= 0 && second < 60) + { + if (millisecond < 0 || millisecond >= MillisPerSecond) + { + throw new ArgumentOutOfRangeException( + "millisecond", + String.Format( + CultureInfo.CurrentCulture, + SR.ArgumentOutOfRange_Range, + 0, + MillisPerSecond - 1)); + } + return (InternalGloablizationHelper.TimeToTicks(hour, minute, second) + millisecond * TicksPerMillisecond); ; + } + throw new ArgumentOutOfRangeException(null, SR.ArgumentOutOfRange_BadHourMinuteSecond); + } + + + internal void CheckTicksRange(long ticks) + { + if (ticks < m_Cal.MinSupportedDateTime.Ticks || ticks > m_Cal.MaxSupportedDateTime.Ticks) + { + throw new ArgumentOutOfRangeException( + "time", + String.Format( + CultureInfo.InvariantCulture, + SR.ArgumentOutOfRange_CalendarRange, + m_Cal.MinSupportedDateTime, + m_Cal.MaxSupportedDateTime)); + } + Contract.EndContractBlock(); + } + + // Returns the DateTime resulting from adding the given number of + // months to the specified DateTime. The result is computed by incrementing + // (or decrementing) the year and month parts of the specified DateTime by + // value months, and, if required, adjusting the day part of the + // resulting date downwards to the last day of the resulting month in the + // resulting year. The time-of-day part of the result is the same as the + // time-of-day part of the specified DateTime. + // + // In more precise terms, considering the specified DateTime to be of the + // form y / m / d + t, where y is the + // year, m is the month, d is the day, and t is the + // time-of-day, the result is y1 / m1 / d1 + t, + // where y1 and m1 are computed by adding value months + // to y and m, and d1 is the largest value less than + // or equal to d that denotes a valid day in month m1 of year + // y1. + // + public DateTime AddMonths(DateTime time, int months) + { + if (months < -120000 || months > 120000) + { + throw new ArgumentOutOfRangeException( + "months", + String.Format( + CultureInfo.CurrentCulture, + SR.ArgumentOutOfRange_Range, + -120000, + 120000)); + } + Contract.EndContractBlock(); + CheckTicksRange(time.Ticks); + + int y = GetDatePart(time.Ticks, DatePartYear); + int m = GetDatePart(time.Ticks, DatePartMonth); + int d = GetDatePart(time.Ticks, DatePartDay); + int i = m - 1 + months; + if (i >= 0) + { + m = i % 12 + 1; + y = y + i / 12; + } + else + { + m = 12 + (i + 1) % 12; + y = y + (i - 11) / 12; + } + int[] daysArray = (y % 4 == 0 && (y % 100 != 0 || y % 400 == 0)) ? DaysToMonth366 : DaysToMonth365; + int days = (daysArray[m] - daysArray[m - 1]); + + if (d > days) + { + d = days; + } + long ticks = DateToTicks(y, m, d) + (time.Ticks % TicksPerDay); + Calendar.CheckAddResult(ticks, m_Cal.MinSupportedDateTime, m_Cal.MaxSupportedDateTime); + return (new DateTime(ticks)); + } + + // Returns the DateTime resulting from adding the given number of + // years to the specified DateTime. The result is computed by incrementing + // (or decrementing) the year part of the specified DateTime by value + // years. If the month and day of the specified DateTime is 2/29, and if the + // resulting year is not a leap year, the month and day of the resulting + // DateTime becomes 2/28. Otherwise, the month, day, and time-of-day + // parts of the result are the same as those of the specified DateTime. + // + public DateTime AddYears(DateTime time, int years) + { + return (AddMonths(time, years * 12)); + } + + // Returns the day-of-month part of the specified DateTime. The returned + // value is an integer between 1 and 31. + // + public int GetDayOfMonth(DateTime time) + { + return (GetDatePart(time.Ticks, DatePartDay)); + } + + // Returns the day-of-week part of the specified DateTime. The returned value + // is an integer between 0 and 6, where 0 indicates Sunday, 1 indicates + // Monday, 2 indicates Tuesday, 3 indicates Wednesday, 4 indicates + // Thursday, 5 indicates Friday, and 6 indicates Saturday. + // + public DayOfWeek GetDayOfWeek(DateTime time) + { + CheckTicksRange(time.Ticks); + return ((DayOfWeek)((time.Ticks / TicksPerDay + 1) % 7)); + } + + // Returns the day-of-year part of the specified DateTime. The returned value + // is an integer between 1 and 366. + // + public int GetDayOfYear(DateTime time) + { + return (GetDatePart(time.Ticks, DatePartDayOfYear)); + } + + // Returns the number of days in the month given by the year and + // month arguments. + // + [Pure] + public int GetDaysInMonth(int year, int month, int era) + { + // + // Convert year/era value to Gregorain year value. + // + year = GetGregorianYear(year, era); + if (month < 1 || month > 12) + { + throw new ArgumentOutOfRangeException("month", SR.ArgumentOutOfRange_Month); + } + int[] days = ((year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) ? DaysToMonth366 : DaysToMonth365); + return (days[month] - days[month - 1]); + } + + // Returns the number of days in the year given by the year argument for the current era. + // + + public int GetDaysInYear(int year, int era) + { + // + // Convert year/era value to Gregorain year value. + // + year = GetGregorianYear(year, era); + return ((year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) ? 366 : 365); + } + + // Returns the era for the specified DateTime value. + public int GetEra(DateTime time) + { + long ticks = time.Ticks; + // The assumption here is that m_EraInfo is listed in reverse order. + for (int i = 0; i < m_EraInfo.Length; i++) + { + if (ticks >= m_EraInfo[i].ticks) + { + return (m_EraInfo[i].era); + } + } + throw new ArgumentOutOfRangeException("time", SR.ArgumentOutOfRange_Era); + } + + + public int[] Eras + { + get + { + if (m_eras == null) + { + m_eras = new int[m_EraInfo.Length]; + for (int i = 0; i < m_EraInfo.Length; i++) + { + m_eras[i] = m_EraInfo[i].era; + } + } + return ((int[])m_eras.Clone()); + } + } + + // Returns the month part of the specified DateTime. The returned value is an + // integer between 1 and 12. + // + public int GetMonth(DateTime time) + { + return (GetDatePart(time.Ticks, DatePartMonth)); + } + + // Returns the number of months in the specified year and era. + public int GetMonthsInYear(int year, int era) + { + year = GetGregorianYear(year, era); + return (12); + } + + // Returns the year part of the specified DateTime. The returned value is an + // integer between 1 and 9999. + // + public int GetYear(DateTime time) + { + long ticks = time.Ticks; + int year = GetDatePart(ticks, DatePartYear); + for (int i = 0; i < m_EraInfo.Length; i++) + { + if (ticks >= m_EraInfo[i].ticks) + { + return (year - m_EraInfo[i].yearOffset); + } + } + throw new ArgumentException(SR.Argument_NoEra); + } + + // Returns the year that match the specified Gregorian year. The returned value is an + // integer between 1 and 9999. + // + public int GetYear(int year, DateTime time) + { + long ticks = time.Ticks; + for (int i = 0; i < m_EraInfo.Length; i++) + { + // while calculating dates with JapaneseLuniSolarCalendar, we can run into cases right after the start of the era + // and still belong to the month which is started in previous era. Calculating equivalent calendar date will cause + // using the new era info which will have the year offset equal to the year we are calculating year = m_EraInfo[i].yearOffset + // which will end up with zero as calendar year. + // We should use the previous era info instead to get the right year number. Example of such date is Feb 2nd 1989 + if (ticks >= m_EraInfo[i].ticks && year > m_EraInfo[i].yearOffset) + { + return (year - m_EraInfo[i].yearOffset); + } + } + throw new ArgumentException(SR.Argument_NoEra); + } + + // Checks whether a given day in the specified era is a leap day. This method returns true if + // the date is a leap day, or false if not. + // + public bool IsLeapDay(int year, int month, int day, int era) + { + // year/month/era checking is done in GetDaysInMonth() + if (day < 1 || day > GetDaysInMonth(year, month, era)) + { + throw new ArgumentOutOfRangeException( + "day", + String.Format( + CultureInfo.CurrentCulture, + SR.ArgumentOutOfRange_Range, + 1, + GetDaysInMonth(year, month, era))); + } + Contract.EndContractBlock(); + + if (!IsLeapYear(year, era)) + { + return (false); + } + + if (month == 2 && day == 29) + { + return (true); + } + + return (false); + } + + // Returns the leap month in a calendar year of the specified era. This method returns 0 + // if this calendar does not have leap month, or this year is not a leap year. + // + public int GetLeapMonth(int year, int era) + { + year = GetGregorianYear(year, era); + return (0); + } + + // Checks whether a given month in the specified era is a leap month. This method returns true if + // month is a leap month, or false if not. + // + public bool IsLeapMonth(int year, int month, int era) + { + year = GetGregorianYear(year, era); + if (month < 1 || month > 12) + { + throw new ArgumentOutOfRangeException( + "month", + String.Format( + CultureInfo.CurrentCulture, + SR.ArgumentOutOfRange_Range, + 1, + 12)); + } + return (false); + } + + // Checks whether a given year in the specified era is a leap year. This method returns true if + // year is a leap year, or false if not. + // + public bool IsLeapYear(int year, int era) + { + year = GetGregorianYear(year, era); + return (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)); + } + + // Returns the date and time converted to a DateTime value. Throws an exception if the n-tuple is invalid. + // + public DateTime ToDateTime(int year, int month, int day, int hour, int minute, int second, int millisecond, int era) + { + year = GetGregorianYear(year, era); + long ticks = DateToTicks(year, month, day) + TimeToTicks(hour, minute, second, millisecond); + CheckTicksRange(ticks); + return (new DateTime(ticks)); + } + + public virtual int GetWeekOfYear(DateTime time, CalendarWeekRule rule, DayOfWeek firstDayOfWeek) + { + CheckTicksRange(time.Ticks); + // Use GregorianCalendar to get around the problem that the implmentation in Calendar.GetWeekOfYear() + // can call GetYear() that exceeds the supported range of the Gregorian-based calendars. + return (GregorianCalendar.GetDefaultInstance().GetWeekOfYear(time, rule, firstDayOfWeek)); + } + + + public int ToFourDigitYear(int year, int twoDigitYearMax) + { + if (year < 0) + { + throw new ArgumentOutOfRangeException("year", + SR.ArgumentOutOfRange_NeedPosNum); + } + Contract.EndContractBlock(); + + if (year < 100) + { + int y = year % 100; + return ((twoDigitYearMax / 100 - (y > twoDigitYearMax % 100 ? 1 : 0)) * 100 + y); + } + + if (year < m_minYear || year > m_maxYear) + { + throw new ArgumentOutOfRangeException( + "year", + String.Format( + CultureInfo.CurrentCulture, + SR.ArgumentOutOfRange_Range, m_minYear, m_maxYear)); + } + // If the year value is above 100, just return the year value. Don't have to do + // the TwoDigitYearMax comparison. + return (year); + } + } +} + |