DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (31ec81b5d7bb)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356
/*
*******************************************************************************
* Copyright (C) 1997-2012, International Business Machines Corporation and    *
* others. All Rights Reserved.                                                *
*******************************************************************************
*
* File GREGOCAL.CPP
*
* Modification History:
*
*   Date        Name        Description
*   02/05/97    clhuang     Creation.
*   03/28/97    aliu        Made highly questionable fix to computeFields to
*                           handle DST correctly.
*   04/22/97    aliu        Cleaned up code drastically.  Added monthLength().
*                           Finished unimplemented parts of computeTime() for
*                           week-based date determination.  Removed quetionable
*                           fix and wrote correct fix for computeFields() and
*                           daylight time handling.  Rewrote inDaylightTime()
*                           and computeFields() to handle sensitive Daylight to
*                           Standard time transitions correctly.
*   05/08/97    aliu        Added code review changes.  Fixed isLeapYear() to
*                           not cutover.
*   08/12/97    aliu        Added equivalentTo.  Misc other fixes.  Updated
*                           add() from Java source.
*    07/28/98    stephen        Sync up with JDK 1.2
*    09/14/98    stephen        Changed type of kOneDay, kOneWeek to double.
*                            Fixed bug in roll() 
*   10/15/99    aliu        Fixed j31, incorrect WEEK_OF_YEAR computation.
*   10/15/99    aliu        Fixed j32, cannot set date to Feb 29 2000 AD.
*                           {JDK bug 4210209 4209272}
*   11/15/99    weiv        Added YEAR_WOY and DOW_LOCAL computation
*                           to timeToFields method, updated kMinValues, kMaxValues & kLeastMaxValues
*   12/09/99    aliu        Fixed j81, calculation errors and roll bugs
*                           in year of cutover.
*   01/24/2000  aliu        Revised computeJulianDay for YEAR YEAR_WOY WOY.
********************************************************************************
*/

#include "unicode/utypes.h"
#include <float.h>

#if !UCONFIG_NO_FORMATTING

#include "unicode/gregocal.h"
#include "gregoimp.h"
#include "umutex.h"
#include "uassert.h"

// *****************************************************************************
// class GregorianCalendar
// *****************************************************************************

/**
* Note that the Julian date used here is not a true Julian date, since
* it is measured from midnight, not noon.  This value is the Julian
* day number of January 1, 1970 (Gregorian calendar) at noon UTC. [LIU]
*/

static const int16_t kNumDays[]
= {0,31,59,90,120,151,181,212,243,273,304,334}; // 0-based, for day-in-year
static const int16_t kLeapNumDays[]
= {0,31,60,91,121,152,182,213,244,274,305,335}; // 0-based, for day-in-year
static const int8_t kMonthLength[]
= {31,28,31,30,31,30,31,31,30,31,30,31}; // 0-based
static const int8_t kLeapMonthLength[]
= {31,29,31,30,31,30,31,31,30,31,30,31}; // 0-based

// setTimeInMillis() limits the Julian day range to +/-7F000000.
// This would seem to limit the year range to:
//  ms=+183882168921600000  jd=7f000000  December 20, 5828963 AD
//  ms=-184303902528000000  jd=81000000  September 20, 5838270 BC
// HOWEVER, CalendarRegressionTest/Test4167060 shows that the actual
// range limit on the year field is smaller (~ +/-140000). [alan 3.0]

static const int32_t kGregorianCalendarLimits[UCAL_FIELD_COUNT][4] = {
    // Minimum  Greatest    Least  Maximum
    //           Minimum  Maximum
    {        0,        0,        1,        1}, // ERA
    {        1,        1,   140742,   144683}, // YEAR
    {        0,        0,       11,       11}, // MONTH
    {        1,        1,       52,       53}, // WEEK_OF_YEAR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
    {        1,        1,       28,       31}, // DAY_OF_MONTH
    {        1,        1,      365,      366}, // DAY_OF_YEAR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
    {       -1,       -1,        4,        5}, // DAY_OF_WEEK_IN_MONTH
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
    {  -140742,  -140742,   140742,   144683}, // YEAR_WOY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
    {  -140742,  -140742,   140742,   144683}, // EXTENDED_YEAR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
};

/*
* <pre>
*                            Greatest       Least 
* Field name        Minimum   Minimum     Maximum     Maximum
* ----------        -------   -------     -------     -------
* ERA                     0         0           1           1
* YEAR                    1         1      140742      144683
* MONTH                   0         0          11          11
* WEEK_OF_YEAR            1         1          52          53
* WEEK_OF_MONTH           0         0           4           6
* DAY_OF_MONTH            1         1          28          31
* DAY_OF_YEAR             1         1         365         366
* DAY_OF_WEEK             1         1           7           7
* DAY_OF_WEEK_IN_MONTH   -1        -1           4           5
* AM_PM                   0         0           1           1
* HOUR                    0         0          11          11
* HOUR_OF_DAY             0         0          23          23
* MINUTE                  0         0          59          59
* SECOND                  0         0          59          59
* MILLISECOND             0         0         999         999
* ZONE_OFFSET           -12*      -12*         12*         12*
* DST_OFFSET              0         0           1*          1*
* YEAR_WOY                1         1      140742      144683
* DOW_LOCAL               1         1           7           7
* </pre>
* (*) In units of one-hour
*/

#if defined( U_DEBUG_CALSVC ) || defined (U_DEBUG_CAL)
#include <stdio.h>
#endif

U_NAMESPACE_BEGIN

UOBJECT_DEFINE_RTTI_IMPLEMENTATION(GregorianCalendar)

// 00:00:00 UTC, October 15, 1582, expressed in ms from the epoch.
// Note that only Italy and other Catholic countries actually
// observed this cutover.  Most other countries followed in
// the next few centuries, some as late as 1928. [LIU]
// in Java, -12219292800000L
//const UDate GregorianCalendar::kPapalCutover = -12219292800000L;
static const uint32_t kCutoverJulianDay = 2299161;
static const UDate kPapalCutover = (2299161.0 - kEpochStartAsJulianDay) * U_MILLIS_PER_DAY;
//static const UDate kPapalCutoverJulian = (2299161.0 - kEpochStartAsJulianDay);

// -------------------------------------

GregorianCalendar::GregorianCalendar(UErrorCode& status)
:   Calendar(status),
fGregorianCutover(kPapalCutover),
fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    setTimeInMillis(getNow(), status);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(TimeZone* zone, UErrorCode& status)
:   Calendar(zone, Locale::getDefault(), status),
fGregorianCutover(kPapalCutover),
fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    setTimeInMillis(getNow(), status);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(const TimeZone& zone, UErrorCode& status)
:   Calendar(zone, Locale::getDefault(), status),
fGregorianCutover(kPapalCutover),
fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    setTimeInMillis(getNow(), status);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(const Locale& aLocale, UErrorCode& status)
:   Calendar(TimeZone::createDefault(), aLocale, status),
fGregorianCutover(kPapalCutover),
fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    setTimeInMillis(getNow(), status);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(TimeZone* zone, const Locale& aLocale,
                                     UErrorCode& status)
                                     :   Calendar(zone, aLocale, status),
                                     fGregorianCutover(kPapalCutover),
                                     fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
                                     fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    setTimeInMillis(getNow(), status);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(const TimeZone& zone, const Locale& aLocale,
                                     UErrorCode& status)
                                     :   Calendar(zone, aLocale, status),
                                     fGregorianCutover(kPapalCutover),
                                     fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
                                     fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    setTimeInMillis(getNow(), status);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date,
                                     UErrorCode& status)
                                     :   Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
                                     fGregorianCutover(kPapalCutover),
                                     fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
                                     fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    set(UCAL_ERA, AD);
    set(UCAL_YEAR, year);
    set(UCAL_MONTH, month);
    set(UCAL_DATE, date);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date,
                                     int32_t hour, int32_t minute, UErrorCode& status)
                                     :   Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
                                     fGregorianCutover(kPapalCutover),
                                     fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
                                     fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    set(UCAL_ERA, AD);
    set(UCAL_YEAR, year);
    set(UCAL_MONTH, month);
    set(UCAL_DATE, date);
    set(UCAL_HOUR_OF_DAY, hour);
    set(UCAL_MINUTE, minute);
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date,
                                     int32_t hour, int32_t minute, int32_t second,
                                     UErrorCode& status)
                                     :   Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
                                     fGregorianCutover(kPapalCutover),
                                     fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582),
                                     fIsGregorian(TRUE), fInvertGregorian(FALSE)
{
    set(UCAL_ERA, AD);
    set(UCAL_YEAR, year);
    set(UCAL_MONTH, month);
    set(UCAL_DATE, date);
    set(UCAL_HOUR_OF_DAY, hour);
    set(UCAL_MINUTE, minute);
    set(UCAL_SECOND, second);
}

// -------------------------------------

GregorianCalendar::~GregorianCalendar()
{
}

// -------------------------------------

GregorianCalendar::GregorianCalendar(const GregorianCalendar &source)
:   Calendar(source),
fGregorianCutover(source.fGregorianCutover),
fCutoverJulianDay(source.fCutoverJulianDay), fNormalizedGregorianCutover(source.fNormalizedGregorianCutover), fGregorianCutoverYear(source.fGregorianCutoverYear),
fIsGregorian(source.fIsGregorian), fInvertGregorian(source.fInvertGregorian)
{
}

// -------------------------------------

Calendar* GregorianCalendar::clone() const
{
    return new GregorianCalendar(*this);
}

// -------------------------------------

GregorianCalendar &
GregorianCalendar::operator=(const GregorianCalendar &right)
{
    if (this != &right)
    {
        Calendar::operator=(right);
        fGregorianCutover = right.fGregorianCutover;
        fNormalizedGregorianCutover = right.fNormalizedGregorianCutover;
        fGregorianCutoverYear = right.fGregorianCutoverYear;
        fCutoverJulianDay = right.fCutoverJulianDay;
    }
    return *this;
}

// -------------------------------------

UBool GregorianCalendar::isEquivalentTo(const Calendar& other) const
{
    // Calendar override.
    return Calendar::isEquivalentTo(other) &&
        fGregorianCutover == ((GregorianCalendar*)&other)->fGregorianCutover;
}

// -------------------------------------

void
GregorianCalendar::setGregorianChange(UDate date, UErrorCode& status)
{
    if (U_FAILURE(status)) 
        return;

    fGregorianCutover = date;

    // Precompute two internal variables which we use to do the actual
    // cutover computations.  These are the normalized cutover, which is the
    // midnight at or before the cutover, and the cutover year.  The
    // normalized cutover is in pure date milliseconds; it contains no time
    // of day or timezone component, and it used to compare against other
    // pure date values.
    int32_t cutoverDay = (int32_t)ClockMath::floorDivide(fGregorianCutover, (double)kOneDay);
    fNormalizedGregorianCutover = cutoverDay * kOneDay;

    // Handle the rare case of numeric overflow.  If the user specifies a
    // change of UDate(Long.MIN_VALUE), in order to get a pure Gregorian
    // calendar, then the epoch day is -106751991168, which when multiplied
    // by ONE_DAY gives 9223372036794351616 -- the negative value is too
    // large for 64 bits, and overflows into a positive value.  We correct
    // this by using the next day, which for all intents is semantically
    // equivalent.
    if (cutoverDay < 0 && fNormalizedGregorianCutover > 0) {
        fNormalizedGregorianCutover = (cutoverDay + 1) * kOneDay;
    }

    // Normalize the year so BC values are represented as 0 and negative
    // values.
    GregorianCalendar *cal = new GregorianCalendar(getTimeZone(), status);
    /* test for NULL */
    if (cal == 0) {
        status = U_MEMORY_ALLOCATION_ERROR;
        return;
    }
    if(U_FAILURE(status))
        return;
    cal->setTime(date, status);
    fGregorianCutoverYear = cal->get(UCAL_YEAR, status);
    if (cal->get(UCAL_ERA, status) == BC) 
        fGregorianCutoverYear = 1 - fGregorianCutoverYear;
    fCutoverJulianDay = cutoverDay;
    delete cal;
}


void GregorianCalendar::handleComputeFields(int32_t julianDay, UErrorCode& status) {
    int32_t eyear, month, dayOfMonth, dayOfYear, unusedRemainder;


    if(U_FAILURE(status)) { 
        return; 
    }

#if defined (U_DEBUG_CAL)
    fprintf(stderr, "%s:%d: jd%d- (greg's %d)- [cut=%d]\n", 
        __FILE__, __LINE__, julianDay, getGregorianDayOfYear(), fCutoverJulianDay);
#endif


    if (julianDay >= fCutoverJulianDay) {
        month = getGregorianMonth();
        dayOfMonth = getGregorianDayOfMonth();
        dayOfYear = getGregorianDayOfYear();
        eyear = getGregorianYear();
    } else {
        // The Julian epoch day (not the same as Julian Day)
        // is zero on Saturday December 30, 0 (Gregorian).
        int32_t julianEpochDay = julianDay - (kJan1_1JulianDay - 2);
		eyear = (int32_t) ClockMath::floorDivide((4.0*julianEpochDay) + 1464.0, (int32_t) 1461, unusedRemainder);

        // Compute the Julian calendar day number for January 1, eyear
        int32_t january1 = 365*(eyear-1) + ClockMath::floorDivide(eyear-1, (int32_t)4);
        dayOfYear = (julianEpochDay - january1); // 0-based

        // Julian leap years occurred historically every 4 years starting
        // with 8 AD.  Before 8 AD the spacing is irregular; every 3 years
        // from 45 BC to 9 BC, and then none until 8 AD.  However, we don't
        // implement this historical detail; instead, we implement the
        // computatinally cleaner proleptic calendar, which assumes
        // consistent 4-year cycles throughout time.
        UBool isLeap = ((eyear&0x3) == 0); // equiv. to (eyear%4 == 0)

        // Common Julian/Gregorian calculation
        int32_t correction = 0;
        int32_t march1 = isLeap ? 60 : 59; // zero-based DOY for March 1
        if (dayOfYear >= march1) {
            correction = isLeap ? 1 : 2;
        }
        month = (12 * (dayOfYear + correction) + 6) / 367; // zero-based month
        dayOfMonth = dayOfYear - (isLeap?kLeapNumDays[month]:kNumDays[month]) + 1; // one-based DOM
        ++dayOfYear;
#if defined (U_DEBUG_CAL)
        //     fprintf(stderr, "%d - %d[%d] + 1\n", dayOfYear, isLeap?kLeapNumDays[month]:kNumDays[month], month );
        //           fprintf(stderr, "%s:%d:  greg's HCF %d -> %d/%d/%d not %d/%d/%d\n", 
        //                   __FILE__, __LINE__,julianDay,
        //          eyear,month,dayOfMonth,
        //          getGregorianYear(), getGregorianMonth(), getGregorianDayOfMonth()  );
        fprintf(stderr, "%s:%d: doy %d (greg's %d)- [cut=%d]\n", 
            __FILE__, __LINE__, dayOfYear, getGregorianDayOfYear(), fCutoverJulianDay);
#endif

    }

    // [j81] if we are after the cutover in its year, shift the day of the year
    if((eyear == fGregorianCutoverYear) && (julianDay >= fCutoverJulianDay)) {
        //from handleComputeMonthStart
        int32_t gregShift = Grego::gregorianShift(eyear);
#if defined (U_DEBUG_CAL)
        fprintf(stderr, "%s:%d:  gregorian shift %d :::  doy%d => %d [cut=%d]\n",
            __FILE__, __LINE__,gregShift, dayOfYear, dayOfYear+gregShift, fCutoverJulianDay);
#endif
        dayOfYear += gregShift;
    }

    internalSet(UCAL_MONTH, month);
    internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
    internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
    internalSet(UCAL_EXTENDED_YEAR, eyear);
    int32_t era = AD;
    if (eyear < 1) {
        era = BC;
        eyear = 1 - eyear;
    }
    internalSet(UCAL_ERA, era);
    internalSet(UCAL_YEAR, eyear);
}


// -------------------------------------

UDate
GregorianCalendar::getGregorianChange() const
{
    return fGregorianCutover;
}

// -------------------------------------

UBool 
GregorianCalendar::isLeapYear(int32_t year) const
{
    // MSVC complains bitterly if we try to use Grego::isLeapYear here
    // NOTE: year&0x3 == year%4
    return (year >= fGregorianCutoverYear ?
        (((year&0x3) == 0) && ((year%100 != 0) || (year%400 == 0))) : // Gregorian
    ((year&0x3) == 0)); // Julian
}

// -------------------------------------

int32_t GregorianCalendar::handleComputeJulianDay(UCalendarDateFields bestField) 
{
    fInvertGregorian = FALSE;

    int32_t jd = Calendar::handleComputeJulianDay(bestField);

    if((bestField == UCAL_WEEK_OF_YEAR) &&  // if we are doing WOY calculations, we are counting relative to Jan 1 *julian*
        (internalGet(UCAL_EXTENDED_YEAR)==fGregorianCutoverYear) && 
        jd >= fCutoverJulianDay) { 
            fInvertGregorian = TRUE;  // So that the Julian Jan 1 will be used in handleComputeMonthStart
            return Calendar::handleComputeJulianDay(bestField);
        }


        // The following check handles portions of the cutover year BEFORE the
        // cutover itself happens.
        //if ((fIsGregorian==TRUE) != (jd >= fCutoverJulianDay)) {  /*  cutoverJulianDay)) { */
        if ((fIsGregorian==TRUE) != (jd >= fCutoverJulianDay)) {  /*  cutoverJulianDay)) { */
#if defined (U_DEBUG_CAL)
            fprintf(stderr, "%s:%d: jd [invert] %d\n", 
                __FILE__, __LINE__, jd);
#endif
            fInvertGregorian = TRUE;
            jd = Calendar::handleComputeJulianDay(bestField);
#if defined (U_DEBUG_CAL)
            fprintf(stderr, "%s:%d:  fIsGregorian %s, fInvertGregorian %s - ", 
                __FILE__, __LINE__,fIsGregorian?"T":"F", fInvertGregorian?"T":"F");
            fprintf(stderr, " jd NOW %d\n", 
                jd);
#endif
        } else {
#if defined (U_DEBUG_CAL)
            fprintf(stderr, "%s:%d: jd [==] %d - %sfIsGregorian %sfInvertGregorian, %d\n", 
                __FILE__, __LINE__, jd, fIsGregorian?"T":"F", fInvertGregorian?"T":"F", bestField);
#endif
        }

        if(fIsGregorian && (internalGet(UCAL_EXTENDED_YEAR) == fGregorianCutoverYear)) {
            int32_t gregShift = Grego::gregorianShift(internalGet(UCAL_EXTENDED_YEAR));
            if (bestField == UCAL_DAY_OF_YEAR) {
#if defined (U_DEBUG_CAL)
                fprintf(stderr, "%s:%d: [DOY%d] gregorian shift of JD %d += %d\n", 
                    __FILE__, __LINE__, fFields[bestField],jd, gregShift);
#endif
                jd -= gregShift;
            } else if ( bestField == UCAL_WEEK_OF_MONTH ) {
                int32_t weekShift = 14;
#if defined (U_DEBUG_CAL)
                fprintf(stderr, "%s:%d: [WOY/WOM] gregorian week shift of %d += %d\n", 
                    __FILE__, __LINE__, jd, weekShift);
#endif
                jd += weekShift; // shift by weeks for week based fields.
            }
        }

        return jd;
}

int32_t GregorianCalendar::handleComputeMonthStart(int32_t eyear, int32_t month,

                                                   UBool /* useMonth */) const
{
    GregorianCalendar *nonConstThis = (GregorianCalendar*)this; // cast away const

    // If the month is out of range, adjust it into range, and
    // modify the extended year value accordingly.
    if (month < 0 || month > 11) {
        eyear += ClockMath::floorDivide(month, 12, month);
    }

    UBool isLeap = eyear%4 == 0;
    int32_t y = eyear-1;
    int32_t julianDay = 365*y + ClockMath::floorDivide(y, 4) + (kJan1_1JulianDay - 3);

    nonConstThis->fIsGregorian = (eyear >= fGregorianCutoverYear);
#if defined (U_DEBUG_CAL)
    fprintf(stderr, "%s:%d: (hcms%d/%d) fIsGregorian %s, fInvertGregorian %s\n", 
        __FILE__, __LINE__, eyear,month, fIsGregorian?"T":"F", fInvertGregorian?"T":"F");
#endif
    if (fInvertGregorian) {
        nonConstThis->fIsGregorian = !fIsGregorian;
    }
    if (fIsGregorian) {
        isLeap = isLeap && ((eyear%100 != 0) || (eyear%400 == 0));
        // Add 2 because Gregorian calendar starts 2 days after
        // Julian calendar
        int32_t gregShift = Grego::gregorianShift(eyear);
#if defined (U_DEBUG_CAL)
        fprintf(stderr, "%s:%d: (hcms%d/%d) gregorian shift of %d += %d\n", 
            __FILE__, __LINE__, eyear, month, julianDay, gregShift);
#endif
        julianDay += gregShift;
    }

    // At this point julianDay indicates the day BEFORE the first
    // day of January 1, <eyear> of either the Julian or Gregorian
    // calendar.

    if (month != 0) {
        julianDay += isLeap?kLeapNumDays[month]:kNumDays[month];
    }

    return julianDay;
}

int32_t GregorianCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month)  const
{
    // If the month is out of range, adjust it into range, and
    // modify the extended year value accordingly.
    if (month < 0 || month > 11) {
        extendedYear += ClockMath::floorDivide(month, 12, month);
    }

    return isLeapYear(extendedYear) ? kLeapMonthLength[month] : kMonthLength[month];
}

int32_t GregorianCalendar::handleGetYearLength(int32_t eyear) const {
    return isLeapYear(eyear) ? 366 : 365;
}


int32_t
GregorianCalendar::monthLength(int32_t month) const
{
    int32_t year = internalGet(UCAL_EXTENDED_YEAR);
    return handleGetMonthLength(year, month);
}

// -------------------------------------

int32_t
GregorianCalendar::monthLength(int32_t month, int32_t year) const
{
    return isLeapYear(year) ? kLeapMonthLength[month] : kMonthLength[month];
}

// -------------------------------------

int32_t
GregorianCalendar::yearLength(int32_t year) const
{
    return isLeapYear(year) ? 366 : 365;
}

// -------------------------------------

int32_t
GregorianCalendar::yearLength() const
{
    return isLeapYear(internalGet(UCAL_YEAR)) ? 366 : 365;
}

// -------------------------------------

/**
* After adjustments such as add(MONTH), add(YEAR), we don't want the
* month to jump around.  E.g., we don't want Jan 31 + 1 month to go to Mar
* 3, we want it to go to Feb 28.  Adjustments which might run into this
* problem call this method to retain the proper month.
*/
void 
GregorianCalendar::pinDayOfMonth() 
{
    int32_t monthLen = monthLength(internalGet(UCAL_MONTH));
    int32_t dom = internalGet(UCAL_DATE);
    if(dom > monthLen) 
        set(UCAL_DATE, monthLen);
}

// -------------------------------------


UBool
GregorianCalendar::validateFields() const
{
    for (int32_t field = 0; field < UCAL_FIELD_COUNT; field++) {
        // Ignore DATE and DAY_OF_YEAR which are handled below
        if (field != UCAL_DATE &&
            field != UCAL_DAY_OF_YEAR &&
            isSet((UCalendarDateFields)field) &&
            ! boundsCheck(internalGet((UCalendarDateFields)field), (UCalendarDateFields)field))
            return FALSE;
    }

    // Values differ in Least-Maximum and Maximum should be handled
    // specially.
    if (isSet(UCAL_DATE)) {
        int32_t date = internalGet(UCAL_DATE);
        if (date < getMinimum(UCAL_DATE) ||
            date > monthLength(internalGet(UCAL_MONTH))) {
                return FALSE;
            }
    }

    if (isSet(UCAL_DAY_OF_YEAR)) {
        int32_t days = internalGet(UCAL_DAY_OF_YEAR);
        if (days < 1 || days > yearLength()) {
            return FALSE;
        }
    }

    // Handle DAY_OF_WEEK_IN_MONTH, which must not have the value zero.
    // We've checked against minimum and maximum above already.
    if (isSet(UCAL_DAY_OF_WEEK_IN_MONTH) &&
        0 == internalGet(UCAL_DAY_OF_WEEK_IN_MONTH)) {
            return FALSE;
        }

        return TRUE;
}

// -------------------------------------

UBool
GregorianCalendar::boundsCheck(int32_t value, UCalendarDateFields field) const
{
    return value >= getMinimum(field) && value <= getMaximum(field);
}

// -------------------------------------

UDate 
GregorianCalendar::getEpochDay(UErrorCode& status) 
{
    complete(status);
    // Divide by 1000 (convert to seconds) in order to prevent overflow when
    // dealing with UDate(Long.MIN_VALUE) and UDate(Long.MAX_VALUE).
    double wallSec = internalGetTime()/1000 + (internalGet(UCAL_ZONE_OFFSET) + internalGet(UCAL_DST_OFFSET))/1000;

    return ClockMath::floorDivide(wallSec, kOneDay/1000.0);
}

// -------------------------------------


// -------------------------------------

/**
* Compute the julian day number of the day BEFORE the first day of
* January 1, year 1 of the given calendar.  If julianDay == 0, it
* specifies (Jan. 1, 1) - 1, in whatever calendar we are using (Julian
* or Gregorian).
*/
double GregorianCalendar::computeJulianDayOfYear(UBool isGregorian,
                                                 int32_t year, UBool& isLeap)
{
    isLeap = year%4 == 0;
    int32_t y = year - 1;
    double julianDay = 365.0*y + ClockMath::floorDivide(y, 4) + (kJan1_1JulianDay - 3);

    if (isGregorian) {
        isLeap = isLeap && ((year%100 != 0) || (year%400 == 0));
        // Add 2 because Gregorian calendar starts 2 days after Julian calendar
        julianDay += Grego::gregorianShift(year);
    }

    return julianDay;
}

// /**
//  * Compute the day of week, relative to the first day of week, from
//  * 0..6, of the current DOW_LOCAL or DAY_OF_WEEK fields.  This is
//  * equivalent to get(DOW_LOCAL) - 1.
//  */
// int32_t GregorianCalendar::computeRelativeDOW() const {
//     int32_t relDow = 0;
//     if (fStamp[UCAL_DOW_LOCAL] > fStamp[UCAL_DAY_OF_WEEK]) {
//         relDow = internalGet(UCAL_DOW_LOCAL) - 1; // 1-based
//     } else if (fStamp[UCAL_DAY_OF_WEEK] != kUnset) {
//         relDow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek();
//         if (relDow < 0) relDow += 7;
//     }
//     return relDow;
// }

// /**
//  * Compute the day of week, relative to the first day of week,
//  * from 0..6 of the given julian day.
//  */
// int32_t GregorianCalendar::computeRelativeDOW(double julianDay) const {
//   int32_t relDow = julianDayToDayOfWeek(julianDay) - getFirstDayOfWeek();
//     if (relDow < 0) {
//         relDow += 7;
//     }
//     return relDow;
// }

// /**
//  * Compute the DOY using the WEEK_OF_YEAR field and the julian day
//  * of the day BEFORE January 1 of a year (a return value from
//  * computeJulianDayOfYear).
//  */
// int32_t GregorianCalendar::computeDOYfromWOY(double julianDayOfYear) const {
//     // Compute DOY from day of week plus week of year

//     // Find the day of the week for the first of this year.  This
//     // is zero-based, with 0 being the locale-specific first day of
//     // the week.  Add 1 to get first day of year.
//     int32_t fdy = computeRelativeDOW(julianDayOfYear + 1);

//     return
//         // Compute doy of first (relative) DOW of WOY 1
//         (((7 - fdy) < getMinimalDaysInFirstWeek())
//          ? (8 - fdy) : (1 - fdy))

//         // Adjust for the week number.
//         + (7 * (internalGet(UCAL_WEEK_OF_YEAR) - 1))

//         // Adjust for the DOW
//         + computeRelativeDOW();
// }

// -------------------------------------

double 
GregorianCalendar::millisToJulianDay(UDate millis)
{
    return (double)kEpochStartAsJulianDay + ClockMath::floorDivide(millis, (double)kOneDay);
}

// -------------------------------------

UDate
GregorianCalendar::julianDayToMillis(double julian)
{
    return (UDate) ((julian - kEpochStartAsJulianDay) * (double) kOneDay);
}

// -------------------------------------

int32_t
GregorianCalendar::aggregateStamp(int32_t stamp_a, int32_t stamp_b) 
{
    return (((stamp_a != kUnset && stamp_b != kUnset) 
        ? uprv_max(stamp_a, stamp_b)
        : (int32_t)kUnset));
}

// -------------------------------------

/**
* Roll a field by a signed amount.
* Note: This will be made public later. [LIU]
*/

void 
GregorianCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) {
    roll((UCalendarDateFields) field, amount, status); 
}

void
GregorianCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status)
{
    if((amount == 0) || U_FAILURE(status)) {
        return;
    }

    // J81 processing. (gregorian cutover)
    UBool inCutoverMonth = FALSE;
    int32_t cMonthLen=0; // 'c' for cutover; in days
    int32_t cDayOfMonth=0; // no discontinuity: [0, cMonthLen)
    double cMonthStart=0.0; // in ms

    // Common code - see if we're in the cutover month of the cutover year
    if(get(UCAL_EXTENDED_YEAR, status) == fGregorianCutoverYear) {
        switch (field) {
        case UCAL_DAY_OF_MONTH:
        case UCAL_WEEK_OF_MONTH:
            {
                int32_t max = monthLength(internalGet(UCAL_MONTH));
                UDate t = internalGetTime();
                // We subtract 1 from the DAY_OF_MONTH to make it zero-based, and an
                // additional 10 if we are after the cutover. Thus the monthStart
                // value will be correct iff we actually are in the cutover month.
                cDayOfMonth = internalGet(UCAL_DAY_OF_MONTH) - ((t >= fGregorianCutover) ? 10 : 0);
                cMonthStart = t - ((cDayOfMonth - 1) * kOneDay);
                // A month containing the cutover is 10 days shorter.
                if ((cMonthStart < fGregorianCutover) &&
                    (cMonthStart + (cMonthLen=(max-10))*kOneDay >= fGregorianCutover)) {
                        inCutoverMonth = TRUE;
                    }
            }
        default:
            ;
        }
    }

    switch (field) {
    case UCAL_WEEK_OF_YEAR: {
        // Unlike WEEK_OF_MONTH, WEEK_OF_YEAR never shifts the day of the
        // week.  Also, rolling the week of the year can have seemingly
        // strange effects simply because the year of the week of year
        // may be different from the calendar year.  For example, the
        // date Dec 28, 1997 is the first day of week 1 of 1998 (if
        // weeks start on Sunday and the minimal days in first week is
        // <= 3).
        int32_t woy = get(UCAL_WEEK_OF_YEAR, status);
        // Get the ISO year, which matches the week of year.  This
        // may be one year before or after the calendar year.
        int32_t isoYear = get(UCAL_YEAR_WOY, status);
        int32_t isoDoy = internalGet(UCAL_DAY_OF_YEAR);
        if (internalGet(UCAL_MONTH) == UCAL_JANUARY) {
            if (woy >= 52) {
                isoDoy += handleGetYearLength(isoYear);
            }
        } else {
            if (woy == 1) {
                isoDoy -= handleGetYearLength(isoYear - 1);
            }
        }
        woy += amount;
        // Do fast checks to avoid unnecessary computation:
        if (woy < 1 || woy > 52) {
            // Determine the last week of the ISO year.
            // We do this using the standard formula we use
            // everywhere in this file.  If we can see that the
            // days at the end of the year are going to fall into
            // week 1 of the next year, we drop the last week by
            // subtracting 7 from the last day of the year.
            int32_t lastDoy = handleGetYearLength(isoYear);
            int32_t lastRelDow = (lastDoy - isoDoy + internalGet(UCAL_DAY_OF_WEEK) -
                getFirstDayOfWeek()) % 7;
            if (lastRelDow < 0) lastRelDow += 7;
            if ((6 - lastRelDow) >= getMinimalDaysInFirstWeek()) lastDoy -= 7;
            int32_t lastWoy = weekNumber(lastDoy, lastRelDow + 1);
            woy = ((woy + lastWoy - 1) % lastWoy) + 1;
        }
        set(UCAL_WEEK_OF_YEAR, woy);
        set(UCAL_YEAR_WOY,isoYear);
        return;
                            }

    case UCAL_DAY_OF_MONTH:
        if( !inCutoverMonth ) { 
            Calendar::roll(field, amount, status);
            return;
        } else {
            // [j81] 1582 special case for DOM
            // The default computation works except when the current month
            // contains the Gregorian cutover.  We handle this special case
            // here.  [j81 - aliu]
            double monthLen = cMonthLen * kOneDay;
            double msIntoMonth = uprv_fmod(internalGetTime() - cMonthStart +
                amount * kOneDay, monthLen);
            if (msIntoMonth < 0) {
                msIntoMonth += monthLen;
            }
#if defined (U_DEBUG_CAL)
            fprintf(stderr, "%s:%d: roll DOM %d  -> %.0lf ms  \n", 
                __FILE__, __LINE__,amount, cMonthLen, cMonthStart+msIntoMonth);
#endif
            setTimeInMillis(cMonthStart + msIntoMonth, status);
            return;
        }

    case UCAL_WEEK_OF_MONTH:
        if( !inCutoverMonth ) { 
            Calendar::roll(field, amount, status);
            return;
        } else {
#if defined (U_DEBUG_CAL)
            fprintf(stderr, "%s:%d: roll WOM %d ??????????????????? \n", 
                __FILE__, __LINE__,amount);
#endif
            // NOTE: following copied from  the old
            //     GregorianCalendar::roll( WEEK_OF_MONTH )  code 

            // This is tricky, because during the roll we may have to shift
            // to a different day of the week.  For example:

            //    s  m  t  w  r  f  s
            //          1  2  3  4  5
            //    6  7  8  9 10 11 12

            // When rolling from the 6th or 7th back one week, we go to the
            // 1st (assuming that the first partial week counts).  The same
            // thing happens at the end of the month.

            // The other tricky thing is that we have to figure out whether
            // the first partial week actually counts or not, based on the
            // minimal first days in the week.  And we have to use the
            // correct first day of the week to delineate the week
            // boundaries.

            // Here's our algorithm.  First, we find the real boundaries of
            // the month.  Then we discard the first partial week if it
            // doesn't count in this locale.  Then we fill in the ends with
            // phantom days, so that the first partial week and the last
            // partial week are full weeks.  We then have a nice square
            // block of weeks.  We do the usual rolling within this block,
            // as is done elsewhere in this method.  If we wind up on one of
            // the phantom days that we added, we recognize this and pin to
            // the first or the last day of the month.  Easy, eh?

            // Another wrinkle: To fix jitterbug 81, we have to make all this
            // work in the oddball month containing the Gregorian cutover.
            // This month is 10 days shorter than usual, and also contains
            // a discontinuity in the days; e.g., the default cutover month
            // is Oct 1582, and goes from day of month 4 to day of month 15.

            // Normalize the DAY_OF_WEEK so that 0 is the first day of the week
            // in this locale.  We have dow in 0..6.
            int32_t dow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek();
            if (dow < 0) 
                dow += 7;

            // Find the day of month, compensating for cutover discontinuity.
            int32_t dom = cDayOfMonth;

            // Find the day of the week (normalized for locale) for the first
            // of the month.
            int32_t fdm = (dow - dom + 1) % 7;
            if (fdm < 0) 
                fdm += 7;

            // Get the first day of the first full week of the month,
            // including phantom days, if any.  Figure out if the first week
            // counts or not; if it counts, then fill in phantom days.  If
            // not, advance to the first real full week (skip the partial week).
            int32_t start;
            if ((7 - fdm) < getMinimalDaysInFirstWeek())
                start = 8 - fdm; // Skip the first partial week
            else
                start = 1 - fdm; // This may be zero or negative

            // Get the day of the week (normalized for locale) for the last
            // day of the month.
            int32_t monthLen = cMonthLen;
            int32_t ldm = (monthLen - dom + dow) % 7;
            // We know monthLen >= DAY_OF_MONTH so we skip the += 7 step here.

            // Get the limit day for the blocked-off rectangular month; that
            // is, the day which is one past the last day of the month,
            // after the month has already been filled in with phantom days
            // to fill out the last week.  This day has a normalized DOW of 0.
            int32_t limit = monthLen + 7 - ldm;

            // Now roll between start and (limit - 1).
            int32_t gap = limit - start;
            int32_t newDom = (dom + amount*7 - start) % gap;
            if (newDom < 0) 
                newDom += gap;
            newDom += start;

            // Finally, pin to the real start and end of the month.
            if (newDom < 1) 
                newDom = 1;
            if (newDom > monthLen) 
                newDom = monthLen;

            // Set the DAY_OF_MONTH.  We rely on the fact that this field
            // takes precedence over everything else (since all other fields
            // are also set at this point).  If this fact changes (if the
            // disambiguation algorithm changes) then we will have to unset
            // the appropriate fields here so that DAY_OF_MONTH is attended
            // to.

            // If we are in the cutover month, manipulate ms directly.  Don't do
            // this in general because it doesn't work across DST boundaries
            // (details, details).  This takes care of the discontinuity.
            setTimeInMillis(cMonthStart + (newDom-1)*kOneDay, status);                
            return;
        }

    default:
        Calendar::roll(field, amount, status);
        return;
    }
}

// -------------------------------------


/**
* Return the minimum value that this field could have, given the current date.
* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
* @param field    the time field.
* @return         the minimum value that this field could have, given the current date.
* @deprecated ICU 2.6. Use getActualMinimum(UCalendarDateFields field) instead.
*/
int32_t GregorianCalendar::getActualMinimum(EDateFields field) const
{
    return getMinimum((UCalendarDateFields)field);
}

int32_t GregorianCalendar::getActualMinimum(EDateFields field, UErrorCode& /* status */) const
{
    return getMinimum((UCalendarDateFields)field);
}

/**
* Return the minimum value that this field could have, given the current date.
* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
* @param field    the time field.
* @return         the minimum value that this field could have, given the current date.
* @draft ICU 2.6.
*/
int32_t GregorianCalendar::getActualMinimum(UCalendarDateFields field, UErrorCode& /* status */) const
{
    return getMinimum(field);
}


// ------------------------------------

/**
* Old year limits were least max 292269054, max 292278994.
*/

/**
* @stable ICU 2.0
*/
int32_t GregorianCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
    return kGregorianCalendarLimits[field][limitType];
}

/**
* Return the maximum value that this field could have, given the current date.
* For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual
* maximum would be 28; for "Feb 3, 1996" it s 29.  Similarly for a Hebrew calendar,
* for some years the actual maximum for MONTH is 12, and for others 13.
* @stable ICU 2.0
*/
int32_t GregorianCalendar::getActualMaximum(UCalendarDateFields field, UErrorCode& status) const
{
    /* It is a known limitation that the code here (and in getActualMinimum)
    * won't behave properly at the extreme limits of GregorianCalendar's
    * representable range (except for the code that handles the YEAR
    * field).  That's because the ends of the representable range are at
    * odd spots in the year.  For calendars with the default Gregorian
    * cutover, these limits are Sun Dec 02 16:47:04 GMT 292269055 BC to Sun
    * Aug 17 07:12:55 GMT 292278994 AD, somewhat different for non-GMT
    * zones.  As a result, if the calendar is set to Aug 1 292278994 AD,
    * the actual maximum of DAY_OF_MONTH is 17, not 30.  If the date is Mar
    * 31 in that year, the actual maximum month might be Jul, whereas is
    * the date is Mar 15, the actual maximum might be Aug -- depending on
    * the precise semantics that are desired.  Similar considerations
    * affect all fields.  Nonetheless, this effect is sufficiently arcane
    * that we permit it, rather than complicating the code to handle such
    * intricacies. - liu 8/20/98

    * UPDATE: No longer true, since we have pulled in the limit values on
    * the year. - Liu 11/6/00 */

    switch (field) {

    case UCAL_YEAR:
        /* The year computation is no different, in principle, from the
        * others, however, the range of possible maxima is large.  In
        * addition, the way we know we've exceeded the range is different.
        * For these reasons, we use the special case code below to handle
        * this field.
        *
        * The actual maxima for YEAR depend on the type of calendar:
        *
        *     Gregorian = May 17, 292275056 BC - Aug 17, 292278994 AD
        *     Julian    = Dec  2, 292269055 BC - Jan  3, 292272993 AD
        *     Hybrid    = Dec  2, 292269055 BC - Aug 17, 292278994 AD
        *
        * We know we've exceeded the maximum when either the month, date,
        * time, or era changes in response to setting the year.  We don't
        * check for month, date, and time here because the year and era are
        * sufficient to detect an invalid year setting.  NOTE: If code is
        * added to check the month and date in the future for some reason,
        * Feb 29 must be allowed to shift to Mar 1 when setting the year.
        */
        {
            if(U_FAILURE(status)) return 0;
            Calendar *cal = clone();
            if(!cal) {
                status = U_MEMORY_ALLOCATION_ERROR;
                return 0;
            }

            cal->setLenient(TRUE);

            int32_t era = cal->get(UCAL_ERA, status);
            UDate d = cal->getTime(status);

            /* Perform a binary search, with the invariant that lowGood is a
            * valid year, and highBad is an out of range year.
            */
            int32_t lowGood = kGregorianCalendarLimits[UCAL_YEAR][1];
            int32_t highBad = kGregorianCalendarLimits[UCAL_YEAR][2]+1;
            while ((lowGood + 1) < highBad) {
                int32_t y = (lowGood + highBad) / 2;
                cal->set(UCAL_YEAR, y);
                if (cal->get(UCAL_YEAR, status) == y && cal->get(UCAL_ERA, status) == era) {
                    lowGood = y;
                } else {
                    highBad = y;
                    cal->setTime(d, status); // Restore original fields
                }
            }

            delete cal;
            return lowGood;
        }

    default:
        return Calendar::getActualMaximum(field,status);
    }
}


int32_t GregorianCalendar::handleGetExtendedYear() {
    // the year to return
    int32_t year = kEpochYear;

    // year field to use
    int32_t yearField = UCAL_EXTENDED_YEAR;

    // There are three separate fields which could be used to
    // derive the proper year.  Use the one most recently set.
    if (fStamp[yearField] < fStamp[UCAL_YEAR])
        yearField = UCAL_YEAR;
    if (fStamp[yearField] < fStamp[UCAL_YEAR_WOY])
        yearField = UCAL_YEAR_WOY;

    // based on the "best" year field, get the year
    switch(yearField) {
    case UCAL_EXTENDED_YEAR:
        year = internalGet(UCAL_EXTENDED_YEAR, kEpochYear);
        break;

    case UCAL_YEAR:
        {
            // The year defaults to the epoch start, the era to AD
            int32_t era = internalGet(UCAL_ERA, AD);
            if (era == BC) {
                year = 1 - internalGet(UCAL_YEAR, 1); // Convert to extended year
            } else {
                year = internalGet(UCAL_YEAR, kEpochYear);
            }
        }
        break;

    case UCAL_YEAR_WOY:
        year = handleGetExtendedYearFromWeekFields(internalGet(UCAL_YEAR_WOY), internalGet(UCAL_WEEK_OF_YEAR));
#if defined (U_DEBUG_CAL)
        //    if(internalGet(UCAL_YEAR_WOY) != year) {
        fprintf(stderr, "%s:%d: hGEYFWF[%d,%d] ->  %d\n", 
            __FILE__, __LINE__,internalGet(UCAL_YEAR_WOY),internalGet(UCAL_WEEK_OF_YEAR),year);
        //}
#endif
        break;

    default:
        year = kEpochYear;
    }
    return year;
}

int32_t GregorianCalendar::handleGetExtendedYearFromWeekFields(int32_t yearWoy, int32_t woy)
{
    // convert year to extended form
    int32_t era = internalGet(UCAL_ERA, AD);
    if(era == BC) {
        yearWoy = 1 - yearWoy;
    }
    return Calendar::handleGetExtendedYearFromWeekFields(yearWoy, woy);
}


// -------------------------------------

UBool
GregorianCalendar::inDaylightTime(UErrorCode& status) const
{
    if (U_FAILURE(status) || !getTimeZone().useDaylightTime()) 
        return FALSE;

    // Force an update of the state of the Calendar.
    ((GregorianCalendar*)this)->complete(status); // cast away const

    return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
}

// -------------------------------------

/**
* Return the ERA.  We need a special method for this because the
* default ERA is AD, but a zero (unset) ERA is BC.
*/
int32_t
GregorianCalendar::internalGetEra() const {
    return isSet(UCAL_ERA) ? internalGet(UCAL_ERA) : (int32_t)AD;
}

const char *
GregorianCalendar::getType() const {
    //static const char kGregorianType = "gregorian";

    return "gregorian";
}

const UDate     GregorianCalendar::fgSystemDefaultCentury        = DBL_MIN;
const int32_t   GregorianCalendar::fgSystemDefaultCenturyYear    = -1;

UDate           GregorianCalendar::fgSystemDefaultCenturyStart       = DBL_MIN;
int32_t         GregorianCalendar::fgSystemDefaultCenturyStartYear   = -1;


UBool GregorianCalendar::haveDefaultCentury() const
{
    return TRUE;
}

UDate GregorianCalendar::defaultCenturyStart() const
{
    return internalGetDefaultCenturyStart();
}

int32_t GregorianCalendar::defaultCenturyStartYear() const
{
    return internalGetDefaultCenturyStartYear();
}

UDate
GregorianCalendar::internalGetDefaultCenturyStart() const
{
    // lazy-evaluate systemDefaultCenturyStart
    UBool needsUpdate;
    UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);

    if (needsUpdate) {
        initializeSystemDefaultCentury();
    }

    // use defaultCenturyStart unless it's the flag value;
    // then use systemDefaultCenturyStart

    return fgSystemDefaultCenturyStart;
}

int32_t
GregorianCalendar::internalGetDefaultCenturyStartYear() const
{
    // lazy-evaluate systemDefaultCenturyStartYear
    UBool needsUpdate;
    UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);

    if (needsUpdate) {
        initializeSystemDefaultCentury();
    }

    // use defaultCenturyStart unless it's the flag value;
    // then use systemDefaultCenturyStartYear

    return fgSystemDefaultCenturyStartYear;
}

void
GregorianCalendar::initializeSystemDefaultCentury()
{
    // initialize systemDefaultCentury and systemDefaultCenturyYear based
    // on the current time.  They'll be set to 80 years before
    // the current time.
    UErrorCode status = U_ZERO_ERROR;
    Calendar *calendar = new GregorianCalendar(status);
    if (calendar != NULL && U_SUCCESS(status))
    {
        calendar->setTime(Calendar::getNow(), status);
        calendar->add(UCAL_YEAR, -80, status);

        UDate    newStart =  calendar->getTime(status);
        int32_t  newYear  =  calendar->get(UCAL_YEAR, status);
        umtx_lock(NULL);
        if (fgSystemDefaultCenturyStart == fgSystemDefaultCentury)
        {
            fgSystemDefaultCenturyStartYear = newYear;
            fgSystemDefaultCenturyStart = newStart;
        }
        umtx_unlock(NULL);
        delete calendar;
    }
    // We have no recourse upon failure unless we want to propagate the failure
    // out.
}


U_NAMESPACE_END

#endif /* #if !UCONFIG_NO_FORMATTING */

//eof