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      1 //  2016 and later: Unicode, Inc. and others.
      2 // License & terms of use: http://www.unicode.org/copyright.html
      3 /*
      4 ******************************************************************************
      5 * Copyright (C) 2014-2016, International Business Machines
      6 * Corporation and others.  All Rights Reserved.
      7 ******************************************************************************
      8 * quantityformatter.h
      9 */
     10 
     11 #ifndef __QUANTITY_FORMATTER_H__
     12 #define __QUANTITY_FORMATTER_H__
     13 
     14 #include "unicode/utypes.h"
     15 #include "unicode/uobject.h"
     16 
     17 #if !UCONFIG_NO_FORMATTING
     18 
     19 #include "standardplural.h"
     20 
     21 U_NAMESPACE_BEGIN
     22 
     23 class SimpleFormatter;
     24 class UnicodeString;
     25 class PluralRules;
     26 class NumberFormat;
     27 class Formattable;
     28 class FieldPosition;
     29 
     30 /**
     31  * A plural aware formatter that is good for expressing a single quantity and
     32  * a unit.
     33  * <p>
     34  * First use the add() methods to add a pattern for each plural variant.
     35  * There must be a pattern for the "other" variant.
     36  * Then use the format() method.
     37  * <p>
     38  * Concurrent calls only to const methods on a QuantityFormatter object are
     39  * safe, but concurrent const and non-const method calls on a QuantityFormatter
     40  * object are not safe and require synchronization.
     41  *
     42  */
     43 class U_I18N_API QuantityFormatter : public UMemory {
     44 public:
     45     /**
     46      * Default constructor.
     47      */
     48     QuantityFormatter();
     49 
     50     /**
     51      * Copy constructor.
     52      */
     53     QuantityFormatter(const QuantityFormatter& other);
     54 
     55     /**
     56      * Assignment operator
     57      */
     58     QuantityFormatter &operator=(const QuantityFormatter& other);
     59 
     60     /**
     61      * Destructor.
     62      */
     63     ~QuantityFormatter();
     64 
     65     /**
     66      * Removes all variants from this object including the "other" variant.
     67      */
     68     void reset();
     69 
     70     /**
     71      * Adds a plural variant if there is none yet for the plural form.
     72      *
     73      * @param variant "zero", "one", "two", "few", "many", "other"
     74      * @param rawPattern the pattern for the variant e.g "{0} meters"
     75      * @param status any error returned here.
     76      * @return TRUE on success; FALSE if status was set to a non zero error.
     77      */
     78     UBool addIfAbsent(const char *variant, const UnicodeString &rawPattern, UErrorCode &status);
     79 
     80     /**
     81      * returns TRUE if this object has at least the "other" variant.
     82      */
     83     UBool isValid() const;
     84 
     85     /**
     86      * Gets the pattern formatter that would be used for a particular variant.
     87      * If isValid() returns TRUE, this method is guaranteed to return a
     88      * non-NULL value.
     89      */
     90     const SimpleFormatter *getByVariant(const char *variant) const;
     91 
     92     /**
     93      * Formats a number with this object appending the result to appendTo.
     94      * At least the "other" variant must be added to this object for this
     95      * method to work.
     96      *
     97      * @param number the single number.
     98      * @param fmt formats the number
     99      * @param rules computes the plural variant to use.
    100      * @param appendTo result appended here.
    101      * @param status any error returned here.
    102      * @return appendTo
    103      */
    104     UnicodeString &format(
    105             const Formattable &number,
    106             const NumberFormat &fmt,
    107             const PluralRules &rules,
    108             UnicodeString &appendTo,
    109             FieldPosition &pos,
    110             UErrorCode &status) const;
    111 
    112     /**
    113      * Selects the standard plural form for the number/formatter/rules.
    114      */
    115     static StandardPlural::Form selectPlural(
    116             const Formattable &number,
    117             const NumberFormat &fmt,
    118             const PluralRules &rules,
    119             UnicodeString &formattedNumber,
    120             FieldPosition &pos,
    121             UErrorCode &status);
    122 
    123     /**
    124      * Formats the pattern with the value and adjusts the FieldPosition.
    125      */
    126     static UnicodeString &format(
    127             const SimpleFormatter &pattern,
    128             const UnicodeString &value,
    129             UnicodeString &appendTo,
    130             FieldPosition &pos,
    131             UErrorCode &status);
    132 
    133 private:
    134     SimpleFormatter *formatters[StandardPlural::COUNT];
    135 };
    136 
    137 U_NAMESPACE_END
    138 
    139 #endif
    140 
    141 #endif
    142