icuSources/i18n/quantityformatter.h

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