icuSources/i18n/quantityformatter.h

   1 /*
   2 ******************************************************************************
   3 * Copyright (C) 2014, 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 U_NAMESPACE_BEGIN
  18
  19 class SimplePatternFormatter;
  20 class UnicodeString;
  21 class PluralRules;
  22 class NumberFormat;
  23 class Formattable;
  24 class FieldPosition;
  25
  26 /**
  27  * A plural aware formatter that is good for expressing a single quantity and
  28  * a unit.
  29  * <p>
  30  * First use the add() methods to add a pattern for each plural variant.
  31  * There must be a pattern for the "other" variant.
  32  * Then use the format() method.
  33  * <p>
  34  * Concurrent calls only to const methods on a QuantityFormatter object are
  35  * safe, but concurrent const and non-const method calls on a QuantityFormatter
  36  * object are not safe and require synchronization.
  37  *
  38  */
  39 class U_I18N_API QuantityFormatter : public UMemory {
  40 public:
  41     /**
  42      * Default constructor.
  43      */
  44     QuantityFormatter();
  45
  46     /**
  47      * Copy constructor.
  48      */
  49     QuantityFormatter(const QuantityFormatter& other);
  50
  51     /**
  52      * Assignment operator
  53      */
  54     QuantityFormatter &operator=(const QuantityFormatter& other);
  55
  56     /**
  57      * Destructor.
  58      */
  59     ~QuantityFormatter();
  60
  61     /**
  62      * Removes all variants from this object including the "other" variant.
  63      */
  64     void reset();
  65
  66     /**
  67       * Adds a plural variant.
  68       *
  69       * @param variant "zero", "one", "two", "few", "many", "other"
  70       * @param rawPattern the pattern for the variant e.g "{0} meters"
  71       * @param status any error returned here.
  72       * @return TRUE on success; FALSE if status was set to a non zero error.
  73       */
  74     UBool add(
  75             const char *variant,
  76             const UnicodeString &rawPattern,
  77             UErrorCode &status);
  78
  79     /**
  80      * returns TRUE if this object has at least the "other" variant.
  81      */
  82     UBool isValid() const;
  83
  84     /**
  85      * Gets the pattern formatter that would be used for a particular variant.
  86      * If isValid() returns TRUE, this method is guaranteed to return a
  87      * non-NULL value.
  88      */
  89     const SimplePatternFormatter *getByVariant(const char *variant) const;
  90
  91     /**
  92      * Formats a quantity with this object appending the result to appendTo.
  93      * At least the "other" variant must be added to this object for this
  94      * method to work.
  95      *
  96      * @param quantity the single quantity.
  97      * @param fmt formats the quantity
  98      * @param rules computes the plural variant to use.
  99      * @param appendTo result appended here.
 100      * @param status any error returned here.
 101      * @return appendTo
 102      */
 103     UnicodeString &format(
 104             const Formattable &quantity,
 105             const NumberFormat &fmt,
 106             const PluralRules &rules,
 107             UnicodeString &appendTo,
 108             FieldPosition &pos,
 109             UErrorCode &status) const;
 110
 111 private:
 112     SimplePatternFormatter *formatters[6];
 113 };
 114
 115 U_NAMESPACE_END
 116
 117 #endif
 118
 119 #endif