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 (d38398e5144e)

VCS Links

EAlignmentFields

NumberFormat

NumberFormatFactory

SimpleNumberFormatFactory

Macros

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
// Copyright (C) 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
********************************************************************************
* Copyright (C) 1997-2016, International Business Machines Corporation and others.
* All Rights Reserved.
********************************************************************************
*
* File NUMFMT.H
*
* Modification History:
*
*   Date        Name        Description
*   02/19/97    aliu        Converted from java.
*   03/18/97    clhuang     Updated per C++ implementation.
*   04/17/97    aliu        Changed DigitCount to int per code review.
*    07/20/98    stephen        JDK 1.2 sync up. Added scientific support.
*                            Changed naming conventions to match C++ guidelines
*                            Derecated Java style constants (eg, INTEGER_FIELD)
********************************************************************************
*/

#ifndef NUMFMT_H
#define NUMFMT_H


#include "unicode/utypes.h"

/**
 * \file
 * \brief C++ API: Abstract base class for all number formats.
 */

#if !UCONFIG_NO_FORMATTING

#include "unicode/unistr.h"
#include "unicode/format.h"
#include "unicode/unum.h" // UNumberFormatStyle
#include "unicode/locid.h"
#include "unicode/stringpiece.h"
#include "unicode/curramt.h"
#include "unicode/udisplaycontext.h"

class NumberFormatTest;

U_NAMESPACE_BEGIN

class SharedNumberFormat;

#if !UCONFIG_NO_SERVICE
class NumberFormatFactory;
class StringEnumeration;
#endif

/**
 *
 * Abstract base class for all number formats.  Provides interface for
 * formatting and parsing a number.  Also provides methods for
 * determining which locales have number formats, and what their names
 * are.
 * \headerfile unicode/numfmt.h "unicode/numfmt.h"
 * <P>
 * NumberFormat helps you to format and parse numbers for any locale.
 * Your code can be completely independent of the locale conventions
 * for decimal points, thousands-separators, or even the particular
 * decimal digits used, or whether the number format is even decimal.
 * <P>
 * To format a number for the current Locale, use one of the static
 * factory methods:
 * \code
 *    #include <iostream>
 *    #include "unicode/numfmt.h"
 *    #include "unicode/unistr.h"
 *    #include "unicode/ustream.h"
 *    using namespace std;
 *    
 *    int main() {
 *        double myNumber = 7.0;
 *        UnicodeString myString;
 *        UErrorCode success = U_ZERO_ERROR;
 *        NumberFormat* nf = NumberFormat::createInstance(success);
 *        nf->format(myNumber, myString);
 *        cout << " Example 1: " << myString << endl;
 *    }
 * \endcode
 * Note that there are additional factory methods within subclasses of
 * NumberFormat.
 * <P>
 * If you are formatting multiple numbers, it is more efficient to get
 * the format and use it multiple times so that the system doesn't
 * have to fetch the information about the local language and country
 * conventions multiple times.
 * \code
 *     UnicodeString myString;
 *     UErrorCode success = U_ZERO_ERROR;
 *     NumberFormat *nf = NumberFormat::createInstance( success );
 *     for (int32_t number: {123, 3333, -1234567}) {
 *         nf->format(number, myString);
 *         myString += "; ";
 *     }
 *     cout << " Example 2: " << myString << endl;
 * \endcode
 * To format a number for a different Locale, specify it in the
 * call to \c createInstance().
 * \code
 *     nf = NumberFormat::createInstance(Locale::getFrench(), success);
 * \endcode
 * You can use a \c NumberFormat to parse also.
 * \code
 *    UErrorCode success;
 *    Formattable result(-999);  // initialized with error code
 *    nf->parse(myString, result, success);
 * \endcode
 * Use \c createInstance() to get the normal number format for a \c Locale.
 * There are other static factory methods available.  Use \c createCurrencyInstance()
 * to get the currency number format for that country.  Use \c createPercentInstance()
 * to get a format for displaying percentages. With this format, a
 * fraction from 0.53 is displayed as 53%.
 * <P>
 * The type of number formatting can be specified by passing a 'style' parameter to \c createInstance().
 * For example, use\n
 * \c createInstance(locale, UNUM_DECIMAL, errorCode) to get the normal number format,\n
 * \c createInstance(locale, UNUM_PERCENT, errorCode) to get a format for displaying percentage,\n
 * \c createInstance(locale, UNUM_SCIENTIFIC, errorCode) to get a format for displaying scientific number,\n
 * \c createInstance(locale, UNUM_CURRENCY, errorCode) to get the currency number format,
 * in which the currency is represented by its symbol, for example, "$3.00".\n
 * \c createInstance(locale, UNUM_CURRENCY_ISO, errorCode)  to get the currency number format,
 * in which the currency is represented by its ISO code, for example "USD3.00".\n
 * \c createInstance(locale, UNUM_CURRENCY_PLURAL, errorCode) to get the currency number format,
 * in which the currency is represented by its full name in plural format,
 * for example, "3.00 US dollars" or "1.00 US dollar".
 * <P>
 * You can also control the display of numbers with such methods as
 * \c getMinimumFractionDigits().  If you want even more control over the
 * format or parsing, or want to give your users more control, you can
 * try dynamic_casting the \c NumberFormat you get from the factory methods to a
 * \c DecimalFormat. This will work for the vast majority of
 * countries; just remember to test for NULL in case you
 * encounter an unusual one.
 * <P>
 * You can also use forms of the parse and format methods with
 * \c ParsePosition and \c FieldPosition to allow you to:
 * <ul type=round>
 *   <li>(a) progressively parse through pieces of a string.
 *   <li>(b) align the decimal point and other areas.
 * </ul>
 * For example, you can align numbers in two ways.
 * <P>
 * If you are using a monospaced font with spacing for alignment, you
 * can pass the \c FieldPosition in your format call, with field =
 * \c UNUM_INTEGER_FIELD. On output, \c getEndIndex will be set to the offset
 * between the last character of the integer and the decimal. Add
 * (desiredSpaceCount - getEndIndex) spaces at the front of the
 * string.
 * <P>
 * If you are using proportional fonts, instead of padding with
 * spaces, measure the width of the string in pixels from the start to
 * getEndIndex.  Then move the pen by (desiredPixelWidth -
 * widthToAlignmentPoint) before drawing the text.  It also works
 * where there is no decimal, but possibly additional characters at
 * the end, e.g. with parentheses in negative numbers: "(12)" for -12.
 * <p>
 * <em>User subclasses are not supported.</em> While clients may write
 * subclasses, such code will not necessarily work and will not be
 * guaranteed to work stably from release to release.
 *
 * @stable ICU 2.0
 */
class U_I18N_API NumberFormat : public Format {
public:
    /**
     * Alignment Field constants used to construct a FieldPosition object.
     * Signifies that the position of the integer part or fraction part of
     * a formatted number should be returned.
     *
     * Note: as of ICU 4.4, the values in this enum have been extended to
     * support identification of all number format fields, not just those
     * pertaining to alignment.
     *
     * These constants are provided for backwards compatibility only.
     * Please use the C style constants defined in the header file unum.h.
     *
     * @see FieldPosition
     * @stable ICU 2.0
     */
    enum EAlignmentFields {
        /** @stable ICU 2.0 */
        kIntegerField = UNUM_INTEGER_FIELD,
        /** @stable ICU 2.0 */
        kFractionField = UNUM_FRACTION_FIELD,
        /** @stable ICU 2.0 */
        kDecimalSeparatorField = UNUM_DECIMAL_SEPARATOR_FIELD,
        /** @stable ICU 2.0 */
        kExponentSymbolField = UNUM_EXPONENT_SYMBOL_FIELD,
        /** @stable ICU 2.0 */
        kExponentSignField = UNUM_EXPONENT_SIGN_FIELD,
        /** @stable ICU 2.0 */
        kExponentField = UNUM_EXPONENT_FIELD,
        /** @stable ICU 2.0 */
        kGroupingSeparatorField = UNUM_GROUPING_SEPARATOR_FIELD,
        /** @stable ICU 2.0 */
        kCurrencyField = UNUM_CURRENCY_FIELD,
        /** @stable ICU 2.0 */
        kPercentField = UNUM_PERCENT_FIELD,
        /** @stable ICU 2.0 */
        kPermillField = UNUM_PERMILL_FIELD,
        /** @stable ICU 2.0 */
        kSignField = UNUM_SIGN_FIELD,

    /**
     * These constants are provided for backwards compatibility only.
     * Please use the constants defined in the header file unum.h.
     */
        /** @stable ICU 2.0 */
        INTEGER_FIELD        = UNUM_INTEGER_FIELD,
        /** @stable ICU 2.0 */
        FRACTION_FIELD       = UNUM_FRACTION_FIELD
    };

    /**
     * Destructor.
     * @stable ICU 2.0
     */
    virtual ~NumberFormat();

    /**
     * Return true if the given Format objects are semantically equal.
     * Objects of different subclasses are considered unequal.
     * @return    true if the given Format objects are semantically equal.
     * @stable ICU 2.0
     */
    virtual UBool operator==(const Format& other) const;


    using Format::format;

    /**
     * Format an object to produce a string.  This method handles
     * Formattable objects with numeric types. If the Formattable
     * object type is not a numeric type, then it returns a failing
     * UErrorCode.
     *
     * @param obj       The object to format.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
     */
    virtual UnicodeString& format(const Formattable& obj,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos,
                                  UErrorCode& status) const;

    /**
     * Format an object to produce a string.  This method handles
     * Formattable objects with numeric types. If the Formattable
     * object type is not a numeric type, then it returns a failing
     * UErrorCode.
     *
     * @param obj       The object to format.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param posIter   On return, can be used to iterate over positions
     *                  of fields generated by this format call.  Can be
     *                  NULL.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 4.4
     */
    virtual UnicodeString& format(const Formattable& obj,
                                  UnicodeString& appendTo,
                                  FieldPositionIterator* posIter,
                                  UErrorCode& status) const;

    /**
     * Parse a string to produce an object.  This methods handles
     * parsing of numeric strings into Formattable objects with numeric
     * types.
     * <P>
     * Before calling, set parse_pos.index to the offset you want to
     * start parsing at in the source. After calling, parse_pos.index
     * indicates the position after the successfully parsed text.  If
     * an error occurs, parse_pos.index is unchanged.
     * <P>
     * When parsing, leading whitespace is discarded (with successful
     * parse), while trailing whitespace is left as is.
     * <P>
     * See Format::parseObject() for more.
     *
     * @param source    The string to be parsed into an object.
     * @param result    Formattable to be set to the parse result.
     *                  If parse fails, return contents are undefined.
     * @param parse_pos The position to start parsing at. Upon return
     *                  this param is set to the position after the
     *                  last character successfully parsed. If the
     *                  source is not parsed successfully, this param
     *                  will remain unchanged.
     * @return          A newly created Formattable* object, or NULL
     *                  on failure.  The caller owns this and should
     *                  delete it when done.
     * @stable ICU 2.0
     */
    virtual void parseObject(const UnicodeString& source,
                             Formattable& result,
                             ParsePosition& parse_pos) const;

    /**
     * Format a double number. These methods call the NumberFormat
     * pure virtual format() methods with the default FieldPosition.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
     */
    UnicodeString& format(  double number,
                            UnicodeString& appendTo) const;

    /**
     * Format a long number. These methods call the NumberFormat
     * pure virtual format() methods with the default FieldPosition.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
     */
    UnicodeString& format(  int32_t number,
                            UnicodeString& appendTo) const;

    /**
     * Format an int64 number. These methods call the NumberFormat
     * pure virtual format() methods with the default FieldPosition.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.8
     */
    UnicodeString& format(  int64_t number,
                            UnicodeString& appendTo) const;

    /**
     * Format a double number. Concrete subclasses must implement
     * these pure virtual methods.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
     */
    virtual UnicodeString& format(double number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos) const = 0;
    /**
     * Format a double number. By default, the parent function simply
     * calls the base class and does not return an error status.
     * Therefore, the status may be ignored in some subclasses.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @param status    error status
     * @return          Reference to 'appendTo' parameter.
     * @internal
     */
    virtual UnicodeString& format(double number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos,
                                  UErrorCode &status) const;
    /**
     * Format a double number. Subclasses must implement
     * this method.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param posIter   On return, can be used to iterate over positions
     *                  of fields generated by this format call.
     *                  Can be NULL.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 4.4
     */
    virtual UnicodeString& format(double number,
                                  UnicodeString& appendTo,
                                  FieldPositionIterator* posIter,
                                  UErrorCode& status) const;
    /**
     * Format a long number. Concrete subclasses must implement
     * these pure virtual methods.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
    */
    virtual UnicodeString& format(int32_t number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos) const = 0;

    /**
     * Format a long number. Concrete subclasses may override
     * this function to provide status return.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @param status the output status.
     * @return          Reference to 'appendTo' parameter.
     * @internal
    */
    virtual UnicodeString& format(int32_t number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos,
                                  UErrorCode &status) const;

    /**
     * Format an int32 number. Subclasses must implement
     * this method.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param posIter   On return, can be used to iterate over positions
     *                  of fields generated by this format call.
     *                  Can be NULL.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 4.4
     */
    virtual UnicodeString& format(int32_t number,
                                  UnicodeString& appendTo,
                                  FieldPositionIterator* posIter,
                                  UErrorCode& status) const;
    /**
     * Format an int64 number. (Not abstract to retain compatibility
     * with earlier releases, however subclasses should override this
     * method as it just delegates to format(int32_t number...);
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.8
    */
    virtual UnicodeString& format(int64_t number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos) const;

    /**
     * Format an int64 number. (Not abstract to retain compatibility
     * with earlier releases, however subclasses should override this
     * method as it just delegates to format(int32_t number...);
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @internal
    */
    virtual UnicodeString& format(int64_t number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos,
                                  UErrorCode& status) const;
    /**
     * Format an int64 number. Subclasses must implement
     * this method.
     *
     * @param number    The value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param posIter   On return, can be used to iterate over positions
     *                  of fields generated by this format call.
     *                  Can be NULL.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 4.4
     */
    virtual UnicodeString& format(int64_t number,
                                  UnicodeString& appendTo,
                                  FieldPositionIterator* posIter,
                                  UErrorCode& status) const;

    /**
     * Format a decimal number. Subclasses must implement
     * this method.  The syntax of the unformatted number is a "numeric string"
     * as defined in the Decimal Arithmetic Specification, available at
     * http://speleotrove.com/decimal
     *
     * @param number    The unformatted number, as a string, to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param posIter   On return, can be used to iterate over positions
     *                  of fields generated by this format call.
     *                  Can be NULL.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 4.4
     */
    virtual UnicodeString& format(StringPiece number,
                                  UnicodeString& appendTo,
                                  FieldPositionIterator* posIter,
                                  UErrorCode& status) const;
public:
    /**
     * Format a decimal number.
     * The number is a DigitList wrapper onto a floating point decimal number.
     * The default implementation in NumberFormat converts the decimal number
     * to a double and formats that.  Subclasses of NumberFormat that want
     * to specifically handle big decimal numbers must override this method.
     * class DecimalFormat does so.
     *
     * @param number    The number, a DigitList format Decimal Floating Point.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param posIter   On return, can be used to iterate over positions
     *                  of fields generated by this format call.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @internal
     */
    virtual UnicodeString& format(const DigitList &number,
                                  UnicodeString& appendTo,
                                  FieldPositionIterator* posIter,
                                  UErrorCode& status) const;

    /**
     * Format a decimal number.
     * The number is a DigitList wrapper onto a floating point decimal number.
     * The default implementation in NumberFormat converts the decimal number
     * to a double and formats that.  Subclasses of NumberFormat that want
     * to specifically handle big decimal numbers must override this method.
     * class DecimalFormat does so.
     *
     * @param number    The number, a DigitList format Decimal Floating Point.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param pos       On input: an alignment field, if desired.
     *                  On output: the offsets of the alignment field.
     * @param status    Output param filled with success/failure status.
     * @return          Reference to 'appendTo' parameter.
     * @internal
     */
    virtual UnicodeString& format(const DigitList &number,
                                  UnicodeString& appendTo,
                                  FieldPosition& pos,
                                  UErrorCode& status) const;

public:

   /**
    * Return a long if possible (e.g. within range LONG_MAX,
    * LONG_MAX], and with no decimals), otherwise a double.  If
    * IntegerOnly is set, will stop at a decimal point (or equivalent;
    * e.g. for rational numbers "1 2/3", will stop after the 1).
    * <P>
    * If no object can be parsed, index is unchanged, and NULL is
    * returned.
    * <P>
    * This is a pure virtual which concrete subclasses must implement.
    *
    * @param text           The text to be parsed.
    * @param result         Formattable to be set to the parse result.
    *                       If parse fails, return contents are undefined.
    * @param parsePosition  The position to start parsing at on input.
    *                       On output, moved to after the last successfully
    *                       parse character. On parse failure, does not change.
    * @stable ICU 2.0
    */
    virtual void parse(const UnicodeString& text,
                       Formattable& result,
                       ParsePosition& parsePosition) const = 0;

    /**
     * Parse a string as a numeric value, and return a Formattable
     * numeric object. This method parses integers only if IntegerOnly
     * is set.
     *
     * @param text          The text to be parsed.
     * @param result        Formattable to be set to the parse result.
     *                      If parse fails, return contents are undefined.
     * @param status        Output parameter set to a failure error code
     *                      when a failure occurs.
     * @see                 NumberFormat::isParseIntegerOnly
     * @stable ICU 2.0
     */
    virtual void parse(const UnicodeString& text,
                       Formattable& result,
                       UErrorCode& status) const;

    /**
     * Parses text from the given string as a currency amount.  Unlike
     * the parse() method, this method will attempt to parse a generic
     * currency name, searching for a match of this object's locale's
     * currency display names, or for a 3-letter ISO currency code.
     * This method will fail if this format is not a currency format,
     * that is, if it does not contain the currency pattern symbol
     * (U+00A4) in its prefix or suffix.
     *
     * @param text the string to parse
     * @param pos  input-output position; on input, the position within text
     *             to match; must have 0 <= pos.getIndex() < text.length();
     *             on output, the position after the last matched character.
     *             If the parse fails, the position in unchanged upon output.
     * @return     if parse succeeds, a pointer to a newly-created CurrencyAmount
     *             object (owned by the caller) containing information about
     *             the parsed currency; if parse fails, this is NULL.
     * @stable ICU 49
     */
    virtual CurrencyAmount* parseCurrency(const UnicodeString& text,
                                          ParsePosition& pos) const;

    /**
     * Return true if this format will parse numbers as integers
     * only.  For example in the English locale, with ParseIntegerOnly
     * true, the string "1234." would be parsed as the integer value
     * 1234 and parsing would stop at the "." character.  Of course,
     * the exact format accepted by the parse operation is locale
     * dependant and determined by sub-classes of NumberFormat.
     * @return    true if this format will parse numbers as integers
     *            only.
     * @stable ICU 2.0
     */
    UBool isParseIntegerOnly(void) const;

    /**
     * Sets whether or not numbers should be parsed as integers only.
     * @param value    set True, this format will parse numbers as integers
     *                 only.
     * @see isParseIntegerOnly
     * @stable ICU 2.0
     */
    virtual void setParseIntegerOnly(UBool value);

    /**
     * Sets whether lenient parsing should be enabled (it is off by default).
     *
     * @param enable \c TRUE if lenient parsing should be used,
     *               \c FALSE otherwise.
     * @stable ICU 4.8
     */
    virtual void setLenient(UBool enable);

    /**
     * Returns whether lenient parsing is enabled (it is off by default).
     *
     * @return \c TRUE if lenient parsing is enabled,
     *         \c FALSE otherwise.
     * @see #setLenient
     * @stable ICU 4.8
     */
    virtual UBool isLenient(void) const;

    /**
     * Create a default style NumberFormat for the current default locale.
     * The default formatting style is locale dependent.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createInstance(UErrorCode&);

    /**
     * Create a default style NumberFormat for the specified locale.
     * The default formatting style is locale dependent.
     * @param inLocale    the given locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createInstance(const Locale& inLocale,
                                        UErrorCode&);

    /**
     * Create a specific style NumberFormat for the specified locale.
     * @param desiredLocale    the given locale.
     * @param style            the given style.
     * @param errorCode        Output param filled with success/failure status.
     * @return                 A new NumberFormat instance.
     * @stable ICU 4.8
     */
    static NumberFormat* U_EXPORT2 createInstance(const Locale& desiredLocale,
                                                  UNumberFormatStyle style,
                                                  UErrorCode& errorCode);

#ifndef U_HIDE_INTERNAL_API

    /**
     * ICU use only.
     * Creates NumberFormat instance without using the cache.
     * @internal
     */
    static NumberFormat* internalCreateInstance(
            const Locale& desiredLocale,
            UNumberFormatStyle style,
            UErrorCode& errorCode);

    /**
     * ICU use only.
     * Returns handle to the shared, cached NumberFormat instance for given
     * locale. On success, caller must call removeRef() on returned value
     * once it is done with the shared instance.
     * @internal
     */
    static const SharedNumberFormat* U_EXPORT2 createSharedInstance(
            const Locale& inLocale, UNumberFormatStyle style, UErrorCode& status);

#endif  /* U_HIDE_INTERNAL_API */

    /**
     * Returns a currency format for the current default locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createCurrencyInstance(UErrorCode&);

    /**
     * Returns a currency format for the specified locale.
     * @param inLocale    the given locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createCurrencyInstance(const Locale& inLocale,
                                                UErrorCode&);

    /**
     * Returns a percentage format for the current default locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createPercentInstance(UErrorCode&);

    /**
     * Returns a percentage format for the specified locale.
     * @param inLocale    the given locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createPercentInstance(const Locale& inLocale,
                                               UErrorCode&);

    /**
     * Returns a scientific format for the current default locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createScientificInstance(UErrorCode&);

    /**
     * Returns a scientific format for the specified locale.
     * @param inLocale    the given locale.
     * @stable ICU 2.0
     */
    static NumberFormat* U_EXPORT2 createScientificInstance(const Locale& inLocale,
                                                UErrorCode&);

    /**
     * Get the set of Locales for which NumberFormats are installed.
     * @param count    Output param to receive the size of the locales
     * @stable ICU 2.0
     */
    static const Locale* U_EXPORT2 getAvailableLocales(int32_t& count);

#if !UCONFIG_NO_SERVICE
    /**
     * Register a new NumberFormatFactory.  The factory will be adopted.
     * Because ICU may choose to cache NumberFormat objects internally,
     * this must be called at application startup, prior to any calls to
     * NumberFormat::createInstance to avoid undefined behavior.
     * @param toAdopt the NumberFormatFactory instance to be adopted
     * @param status the in/out status code, no special meanings are assigned
     * @return a registry key that can be used to unregister this factory
     * @stable ICU 2.6
     */
    static URegistryKey U_EXPORT2 registerFactory(NumberFormatFactory* toAdopt, UErrorCode& status);

    /**
     * Unregister a previously-registered NumberFormatFactory using the key returned from the
     * register call.  Key becomes invalid after a successful call and should not be used again.
     * The NumberFormatFactory corresponding to the key will be deleted.
     * Because ICU may choose to cache NumberFormat objects internally,
     * this should be called during application shutdown, after all calls to
     * NumberFormat::createInstance to avoid undefined behavior.
     * @param key the registry key returned by a previous call to registerFactory
     * @param status the in/out status code, no special meanings are assigned
     * @return TRUE if the factory for the key was successfully unregistered
     * @stable ICU 2.6
     */
    static UBool U_EXPORT2 unregister(URegistryKey key, UErrorCode& status);

    /**
     * Return a StringEnumeration over the locales available at the time of the call,
     * including registered locales.
     * @return a StringEnumeration over the locales available at the time of the call
     * @stable ICU 2.6
     */
    static StringEnumeration* U_EXPORT2 getAvailableLocales(void);
#endif /* UCONFIG_NO_SERVICE */

    /**
     * Returns true if grouping is used in this format. For example,
     * in the English locale, with grouping on, the number 1234567
     * might be formatted as "1,234,567". The grouping separator as
     * well as the size of each group is locale dependant and is
     * determined by sub-classes of NumberFormat.
     * @see setGroupingUsed
     * @stable ICU 2.0
     */
    UBool isGroupingUsed(void) const;

    /**
     * Set whether or not grouping will be used in this format.
     * @param newValue    True, grouping will be used in this format.
     * @see getGroupingUsed
     * @stable ICU 2.0
     */
    virtual void setGroupingUsed(UBool newValue);

    /**
     * Returns the maximum number of digits allowed in the integer portion of a
     * number.
     * @return     the maximum number of digits allowed in the integer portion of a
     *             number.
     * @see setMaximumIntegerDigits
     * @stable ICU 2.0
     */
    int32_t getMaximumIntegerDigits(void) const;

    /**
     * Sets the maximum number of digits allowed in the integer portion of a
     * number. maximumIntegerDigits must be >= minimumIntegerDigits.  If the
     * new value for maximumIntegerDigits is less than the current value
     * of minimumIntegerDigits, then minimumIntegerDigits will also be set to
     * the new value.
     *
     * @param newValue    the new value for the maximum number of digits
     *                    allowed in the integer portion of a number.
     * @see getMaximumIntegerDigits
     * @stable ICU 2.0
     */
    virtual void setMaximumIntegerDigits(int32_t newValue);

    /**
     * Returns the minimum number of digits allowed in the integer portion of a
     * number.
     * @return    the minimum number of digits allowed in the integer portion of a
     *            number.
     * @see setMinimumIntegerDigits
     * @stable ICU 2.0
     */
    int32_t getMinimumIntegerDigits(void) const;

    /**
     * Sets the minimum number of digits allowed in the integer portion of a
     * number. minimumIntegerDigits must be &lt;= maximumIntegerDigits.  If the
     * new value for minimumIntegerDigits exceeds the current value
     * of maximumIntegerDigits, then maximumIntegerDigits will also be set to
     * the new value.
     * @param newValue    the new value to be set.
     * @see getMinimumIntegerDigits
     * @stable ICU 2.0
     */
    virtual void setMinimumIntegerDigits(int32_t newValue);

    /**
     * Returns the maximum number of digits allowed in the fraction portion of a
     * number.
     * @return    the maximum number of digits allowed in the fraction portion of a
     *            number.
     * @see setMaximumFractionDigits
     * @stable ICU 2.0
     */
    int32_t getMaximumFractionDigits(void) const;

    /**
     * Sets the maximum number of digits allowed in the fraction portion of a
     * number. maximumFractionDigits must be >= minimumFractionDigits.  If the
     * new value for maximumFractionDigits is less than the current value
     * of minimumFractionDigits, then minimumFractionDigits will also be set to
     * the new value.
     * @param newValue    the new value to be set.
     * @see getMaximumFractionDigits
     * @stable ICU 2.0
     */
    virtual void setMaximumFractionDigits(int32_t newValue);

    /**
     * Returns the minimum number of digits allowed in the fraction portion of a
     * number.
     * @return    the minimum number of digits allowed in the fraction portion of a
     *            number.
     * @see setMinimumFractionDigits
     * @stable ICU 2.0
     */
    int32_t getMinimumFractionDigits(void) const;

    /**
     * Sets the minimum number of digits allowed in the fraction portion of a
     * number. minimumFractionDigits must be &lt;= maximumFractionDigits.   If the
     * new value for minimumFractionDigits exceeds the current value
     * of maximumFractionDigits, then maximumIntegerDigits will also be set to
     * the new value
     * @param newValue    the new value to be set.
     * @see getMinimumFractionDigits
     * @stable ICU 2.0
     */
    virtual void setMinimumFractionDigits(int32_t newValue);

    /**
     * Sets the currency used to display currency
     * amounts.  This takes effect immediately, if this format is a
     * currency format.  If this format is not a currency format, then
     * the currency is used if and when this object becomes a
     * currency format.
     * @param theCurrency a 3-letter ISO code indicating new currency
     * to use.  It need not be null-terminated.  May be the empty
     * string or NULL to indicate no currency.
     * @param ec input-output error code
     * @stable ICU 3.0
     */
    virtual void setCurrency(const UChar* theCurrency, UErrorCode& ec);

    /**
     * Gets the currency used to display currency
     * amounts.  This may be an empty string for some subclasses.
     * @return a 3-letter null-terminated ISO code indicating
     * the currency in use, or a pointer to the empty string.
     * @stable ICU 2.6
     */
    const UChar* getCurrency() const;
	
    /**
     * Set a particular UDisplayContext value in the formatter, such as
     * UDISPCTX_CAPITALIZATION_FOR_STANDALONE.
     * @param value The UDisplayContext value to set.
     * @param status Input/output status. If at entry this indicates a failure
     *               status, the function will do nothing; otherwise this will be
     *               updated with any new status from the function.
     * @stable ICU 53
     */
    virtual void setContext(UDisplayContext value, UErrorCode& status);

    /**
     * Get the formatter's UDisplayContext value for the specified UDisplayContextType,
     * such as UDISPCTX_TYPE_CAPITALIZATION.
     * @param type The UDisplayContextType whose value to return
     * @param status Input/output status. If at entry this indicates a failure
     *               status, the function will do nothing; otherwise this will be
     *               updated with any new status from the function.
     * @return The UDisplayContextValue for the specified type.
     * @stable ICU 53
     */
    virtual UDisplayContext getContext(UDisplayContextType type, UErrorCode& status) const;

public:

    /**
     * Return the class ID for this class.  This is useful for
     * comparing to a return value from getDynamicClassID(). Note that,
     * because NumberFormat is an abstract base class, no fully constructed object
     * will have the class ID returned by NumberFormat::getStaticClassID().
     * @return The class ID for all objects of this class.
     * @stable ICU 2.0
     */
    static UClassID U_EXPORT2 getStaticClassID(void);

    /**
     * Returns a unique class ID POLYMORPHICALLY.  Pure virtual override.
     * This method is to implement a simple version of RTTI, since not all
     * C++ compilers support genuine RTTI.  Polymorphic operator==() and
     * clone() methods call this method.
     * <P>
     * @return The class ID for this object. All objects of a
     * given class have the same class ID.  Objects of
     * other classes have different class IDs.
     * @stable ICU 2.0
     */
    virtual UClassID getDynamicClassID(void) const = 0;

protected:

    /**
     * Default constructor for subclass use only.
     * @stable ICU 2.0
     */
    NumberFormat();

    /**
     * Copy constructor.
     * @stable ICU 2.0
     */
    NumberFormat(const NumberFormat&);

    /**
     * Assignment operator.
     * @stable ICU 2.0
     */
    NumberFormat& operator=(const NumberFormat&);

    /**
     * Returns the currency in effect for this formatter.  Subclasses
     * should override this method as needed.  Unlike getCurrency(),
     * this method should never return "".
     * @result output parameter for null-terminated result, which must
     * have a capacity of at least 4
     * @internal
     */
    virtual void getEffectiveCurrency(UChar* result, UErrorCode& ec) const;

#ifndef U_HIDE_INTERNAL_API
    /**
     * Creates the specified number format style of the desired locale.
     * If mustBeDecimalFormat is TRUE, then the returned pointer is
     * either a DecimalFormat or it is NULL.
     * @internal
     */
    static NumberFormat* makeInstance(const Locale& desiredLocale,
                                      UNumberFormatStyle style,
                                      UBool mustBeDecimalFormat,
                                      UErrorCode& errorCode);
#endif  /* U_HIDE_INTERNAL_API */

private:

    static UBool isStyleSupported(UNumberFormatStyle style);

    /**
     * Creates the specified decimal format style of the desired locale.
     * @param desiredLocale    the given locale.
     * @param style            the given style.
     * @param errorCode        Output param filled with success/failure status.
     * @return                 A new NumberFormat instance.
     */
    static NumberFormat* makeInstance(const Locale& desiredLocale,
                                      UNumberFormatStyle style,
                                      UErrorCode& errorCode);

    UBool       fGroupingUsed;
    int32_t     fMaxIntegerDigits;
    int32_t     fMinIntegerDigits;
    int32_t     fMaxFractionDigits;
    int32_t     fMinFractionDigits;

  protected:
    /** \internal */
    static const int32_t gDefaultMaxIntegerDigits;
    /** \internal */
    static const int32_t gDefaultMinIntegerDigits;

  private:
    UBool      fParseIntegerOnly;
    UBool      fLenient; // TRUE => lenient parse is enabled

    // ISO currency code
    UChar      fCurrency[4];

    UDisplayContext fCapitalizationContext;

    friend class ICUNumberFormatFactory; // access to makeInstance
    friend class ICUNumberFormatService;
    friend class ::NumberFormatTest;  // access to isStyleSupported()
};

#if !UCONFIG_NO_SERVICE
/**
 * A NumberFormatFactory is used to register new number formats.  The factory
 * should be able to create any of the predefined formats for each locale it
 * supports.  When registered, the locales it supports extend or override the
 * locale already supported by ICU.
 *
 * @stable ICU 2.6
 */
class U_I18N_API NumberFormatFactory : public UObject {
public:

    /**
     * Destructor
     * @stable ICU 3.0
     */
    virtual ~NumberFormatFactory();

    /**
     * Return true if this factory will be visible.  Default is true.
     * If not visible, the locales supported by this factory will not
     * be listed by getAvailableLocales.
     * @stable ICU 2.6
     */
    virtual UBool visible(void) const = 0;

    /**
     * Return the locale names directly supported by this factory.  The number of names
     * is returned in count;
     * @stable ICU 2.6
     */
    virtual const UnicodeString * getSupportedIDs(int32_t &count, UErrorCode& status) const = 0;

    /**
     * Return a number format of the appropriate type.  If the locale
     * is not supported, return null.  If the locale is supported, but
     * the type is not provided by this service, return null.  Otherwise
     * return an appropriate instance of NumberFormat.
     * @stable ICU 2.6
     */
    virtual NumberFormat* createFormat(const Locale& loc, UNumberFormatStyle formatType) = 0;
};

/**
 * A NumberFormatFactory that supports a single locale.  It can be visible or invisible.
 * @stable ICU 2.6
 */
class U_I18N_API SimpleNumberFormatFactory : public NumberFormatFactory {
protected:
    /**
     * True if the locale supported by this factory is visible.
     * @stable ICU 2.6
     */
    const UBool _visible;

    /**
     * The locale supported by this factory, as a UnicodeString.
     * @stable ICU 2.6
     */
    UnicodeString _id;

public:
    /**
     * @stable ICU 2.6
     */
    SimpleNumberFormatFactory(const Locale& locale, UBool visible = TRUE);

    /**
     * @stable ICU 3.0
     */
    virtual ~SimpleNumberFormatFactory();

    /**
     * @stable ICU 2.6
     */
    virtual UBool visible(void) const;

    /**
     * @stable ICU 2.6
     */
    virtual const UnicodeString * getSupportedIDs(int32_t &count, UErrorCode& status) const;
};
#endif /* #if !UCONFIG_NO_SERVICE */

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

inline UBool
NumberFormat::isParseIntegerOnly() const
{
    return fParseIntegerOnly;
}

inline UBool
NumberFormat::isLenient() const
{
    return fLenient;
}

U_NAMESPACE_END

#endif /* #if !UCONFIG_NO_FORMATTING */

#endif // _NUMFMT
//eof