ICU-551.51.4.tar.gz

[apple/icu.git] / icuSources / i18n / gregoimp.h

diff --git a/icuSources/i18n/gregoimp.h b/icuSources/i18n/gregoimp.h
index 8b1d12c74211919d74f46c585e5da298af108397..f65d1410139dfb0ac318b4d88e9ff0847ed3d684 100644 (file)
--- a/icuSources/i18n/gregoimp.h
+++ b/icuSources/i18n/gregoimp.h
@@ -1,13 +1,14 @@
 /*
-**********************************************************************
-* Copyright (c) 2003-2005, International Business Machines
-* Corporation and others.  All Rights Reserved.
-**********************************************************************
-* Author: Alan Liu
-* Created: September 2 2003
-* Since: ICU 2.8
-**********************************************************************
-*/
+ **********************************************************************
+ * Copyright (c) 2003-2008, International Business Machines
+ * Corporation and others.  All Rights Reserved.
+ **********************************************************************
+ * Author: Alan Liu
+ * Created: September 2 2003
+ * Since: ICU 2.8
+ **********************************************************************
+ */
+
 #ifndef GREGOIMP_H
 #define GREGOIMP_H
 #include "unicode/utypes.h"
@@ -21,9 +22,10 @@ U_NAMESPACE_BEGIN
 
 /**
  * A utility class providing mathematical functions used by time zone
- * and calendar code.  Do not instantiate.
+ * and calendar code.  Do not instantiate.  Formerly just named 'Math'.
+ * @internal
  */
-class Math {
+class ClockMath {
  public:
     /**
      * Divide two integers, returning the floor of the quotient.
@@ -190,6 +192,37 @@ class Grego {
     static inline void dayToFields(double day, int32_t& year, int32_t& month,
                                    int32_t& dom, int32_t& dow);
 
+    /**
+     * Convert a 1970-epoch milliseconds to proleptic Gregorian year,
+     * month, day-of-month, and day-of-week, day of year and millis-in-day.
+     * @param time 1970-epoch milliseconds
+     * @param year output parameter to receive year
+     * @param month output parameter to receive month (0-based, 0==Jan)
+     * @param dom output parameter to receive day-of-month (1-based)
+     * @param dow output parameter to receive day-of-week (1-based, 1==Sun)
+     * @param doy output parameter to receive day-of-year (1-based)
+     * @param mid output parameter to recieve millis-in-day
+     */
+    static void timeToFields(UDate time, int32_t& year, int32_t& month,
+                            int32_t& dom, int32_t& dow, int32_t& doy, int32_t& mid);
+
+    /**
+     * Return the day of week on the 1970-epoch day
+     * @param day the 1970-epoch day (integral value)
+     * @return the day of week
+     */
+    static int32_t dayOfWeek(double day);
+
+    /**
+     * Returns the ordinal number for the specified day of week within the month.
+     * The valid return value is 1, 2, 3, 4 or -1.
+     * @param year Gregorian year, with 0 == 1 BCE, -1 == 2 BCE, etc.
+     * @param month 0-based month, with 0==Jan
+     * @param dom 1-based day of month
+     * @return The ordinal number for the specified day of week within the month
+     */
+    static int32_t dayOfWeekInMonth(int32_t year, int32_t month, int32_t dom);
+
     /**
      * Converts Julian day to time as milliseconds.
      * @param julian the given Julian day number.
@@ -218,7 +251,7 @@ class Grego {
     static const int8_t MONTH_LENGTH[24];
 };
 
-inline double Math::floorDivide(double numerator, double denominator) {
+inline double ClockMath::floorDivide(double numerator, double denominator) {
     return uprv_floor(numerator / denominator);
 }
 
@@ -229,7 +262,7 @@ inline UBool Grego::isLeapYear(int32_t year) {
 
 inline int8_t
 Grego::monthLength(int32_t year, int32_t month) {
-    return MONTH_LENGTH[month + isLeapYear(year)?12:0];
+    return MONTH_LENGTH[month + (isLeapYear(year) ? 12 : 0)];
 }
 
 inline int8_t
@@ -249,12 +282,12 @@ inline double Grego::julianDayToMillis(int32_t julian)
 }
 
 inline int32_t Grego::millisToJulianDay(double millis) {
-  return (int32_t) (kEpochStartAsJulianDay + Math::floorDivide(millis, (double)kOneDay));
+  return (int32_t) (kEpochStartAsJulianDay + ClockMath::floorDivide(millis, (double)kOneDay));
 }
 
 inline int32_t Grego::gregorianShift(int32_t eyear) {
   int32_t y = eyear-1;
-  int32_t gregShift = Math::floorDivide(y, 400) - Math::floorDivide(y, 100) + 2;
+  int32_t gregShift = ClockMath::floorDivide(y, 400) - ClockMath::floorDivide(y, 100) + 2;
   return gregShift;
 }