icuSources/i18n/nfsubs.h

   1 /*
   2 ******************************************************************************
   3 *   Copyright (C) 1997-2007, International Business Machines
   4 *   Corporation and others.  All Rights Reserved.
   5 ******************************************************************************
   6 *   file name:  nfsubs.h
   7 *   encoding:   US-ASCII
   8 *   tab size:   8 (not used)
   9 *   indentation:4
  10 *
  11 * Modification history
  12 * Date        Name      Comments
  13 * 10/11/2001  Doug      Ported from ICU4J
  14 */
  15
  16 #ifndef NFSUBS_H
  17 #define NFSUBS_H
  18
  19 #include "unicode/utypes.h"
  20 #include "unicode/uobject.h"
  21 #include "nfrule.h"
  22
  23 #if U_HAVE_RBNF
  24
  25 #include "unicode/utypes.h"
  26 #include "unicode/decimfmt.h"
  27 #include "nfrs.h"
  28 #include <float.h>
  29
  30 U_NAMESPACE_BEGIN
  31
  32 class NFSubstitution : public UObject {
  33     int32_t pos;
  34     const NFRuleSet* ruleSet;
  35     const DecimalFormat* numberFormat;
  36
  37 protected:
  38     NFSubstitution(int32_t pos,
  39         const NFRuleSet* ruleSet,
  40         const RuleBasedNumberFormat* rbnf,
  41         const UnicodeString& description,
  42         UErrorCode& status);
  43
  44     /**
  45      * Get the Ruleset of the object.
  46      * @return the Ruleset of the object.
  47      */
  48     const NFRuleSet* getRuleSet() const { return ruleSet; }
  49
  50     /**
  51      * get the NumberFormat of this object.
  52      * @return the numberformat of this object.
  53      */
  54     const DecimalFormat* getNumberFormat() const { return numberFormat; }
  55
  56 public:
  57     static NFSubstitution* makeSubstitution(int32_t pos,
  58         const NFRule* rule,
  59         const NFRule* predecessor,
  60         const NFRuleSet* ruleSet,
  61         const RuleBasedNumberFormat* rbnf,
  62         const UnicodeString& description,
  63         UErrorCode& status);
  64
  65     /**
  66      * Destructor.
  67      */
  68     virtual ~NFSubstitution();
  69
  70     /**
  71      * Return true if the given Format objects are semantically equal.
  72      * Objects of different subclasses are considered unequal.
  73      * @param rhs    the object to be compared with.
  74      * @return       true if the given Format objects are semantically equal.
  75      */
  76     virtual UBool operator==(const NFSubstitution& rhs) const;
  77
  78     /**
  79      * Return true if the given Format objects are semantically unequal.
  80      * Objects of different subclasses are considered unequal.
  81      * @param rhs    the object to be compared with.
  82      * @return       true if the given Format objects are semantically unequal.
  83      */
  84     UBool operator!=(const NFSubstitution& rhs) const { return !operator==(rhs); }
  85
  86     /**
  87      * Sets the substitution's divisor.  Used by NFRule.setBaseValue().
  88      * A no-op for all substitutions except multiplier and modulus
  89      * substitutions.
  90      * @param radix The radix of the divisor
  91      * @param exponent The exponent of the divisor
  92      */
  93     virtual void setDivisor(int32_t radix, int32_t exponent, UErrorCode& status);
  94
  95     /**
  96      * Replaces result with the string describing the substitution.
  97      * @param result    Output param which will receive the string.
  98      */
  99     virtual void toString(UnicodeString& result) const;
 100
 101     //-----------------------------------------------------------------------
 102     // formatting
 103     //-----------------------------------------------------------------------
 104
 105     /**
 106      * Performs a mathematical operation on the number, formats it using
 107      * either ruleSet or decimalFormat, and inserts the result into
 108      * toInsertInto.
 109      * @param number The number being formatted.
 110      * @param toInsertInto The string we insert the result into
 111      * @param pos The position in toInsertInto where the owning rule's
 112      * rule text begins (this value is added to this substitution's
 113      * position to determine exactly where to insert the new text)
 114      */
 115     virtual void doSubstitution(int64_t number, UnicodeString& toInsertInto, int32_t pos) const;
 116
 117     /**
 118      * Performs a mathematical operation on the number, formats it using
 119      * either ruleSet or decimalFormat, and inserts the result into
 120      * toInsertInto.
 121      * @param number The number being formatted.
 122      * @param toInsertInto The string we insert the result into
 123      * @param pos The position in toInsertInto where the owning rule's
 124      * rule text begins (this value is added to this substitution's
 125      * position to determine exactly where to insert the new text)
 126      */
 127     virtual void doSubstitution(double number, UnicodeString& toInsertInto, int32_t pos) const;
 128
 129 protected:
 130     /**
 131      * Subclasses override this function to perform some kind of
 132      * mathematical operation on the number.  The result of this operation
 133      * is formatted using the rule set or DecimalFormat that this
 134      * substitution refers to, and the result is inserted into the result
 135      * string.
 136      * @param The number being formatted
 137      * @return The result of performing the opreration on the number
 138      */
 139     virtual int64_t transformNumber(int64_t number) const = 0;
 140
 141     /**
 142      * Subclasses override this function to perform some kind of
 143      * mathematical operation on the number.  The result of this operation
 144      * is formatted using the rule set or DecimalFormat that this
 145      * substitution refers to, and the result is inserted into the result
 146      * string.
 147      * @param The number being formatted
 148      * @return The result of performing the opreration on the number
 149      */
 150     virtual double transformNumber(double number) const = 0;
 151
 152 public:
 153     //-----------------------------------------------------------------------
 154     // parsing
 155     //-----------------------------------------------------------------------
 156
 157     /**
 158      * Parses a string using the rule set or DecimalFormat belonging
 159      * to this substitution.  If there's a match, a mathematical
 160      * operation (the inverse of the one used in formatting) is
 161      * performed on the result of the parse and the value passed in
 162      * and returned as the result.  The parse position is updated to
 163      * point to the first unmatched character in the string.
 164      * @param text The string to parse
 165      * @param parsePosition On entry, ignored, but assumed to be 0.
 166      * On exit, this is updated to point to the first unmatched
 167      * character (or 0 if the substitution didn't match)
 168      * @param baseValue A partial parse result that should be
 169      * combined with the result of this parse
 170      * @param upperBound When searching the rule set for a rule
 171      * matching the string passed in, only rules with base values
 172      * lower than this are considered
 173      * @param lenientParse If true and matching against rules fails,
 174      * the substitution will also try matching the text against
 175      * numerals using a default-costructed NumberFormat.  If false,
 176      * no extra work is done.  (This value is false whenever the
 177      * formatter isn't in lenient-parse mode, but is also false
 178      * under some conditions even when the formatter _is_ in
 179      * lenient-parse mode.)
 180      * @return If there's a match, this is the result of composing
 181      * baseValue with whatever was returned from matching the
 182      * characters.  This will be either a Long or a Double.  If there's
 183      * no match this is new Long(0) (not null), and parsePosition
 184      * is left unchanged.
 185      */
 186     virtual UBool doParse(const UnicodeString& text,
 187         ParsePosition& parsePosition,
 188         double baseValue,
 189         double upperBound,
 190         UBool lenientParse,
 191         Formattable& result) const;
 192
 193     /**
 194      * Derives a new value from the two values passed in.  The two values
 195      * are typically either the base values of two rules (the one containing
 196      * the substitution and the one matching the substitution) or partial
 197      * parse results derived in some other way.  The operation is generally
 198      * the inverse of the operation performed by transformNumber().
 199      * @param newRuleValue The value produced by matching this substitution
 200      * @param oldRuleValue The value that was passed to the substitution
 201      * by the rule that owns it
 202      * @return A third value derived from the other two, representing a
 203      * partial parse result
 204      */
 205     virtual double composeRuleValue(double newRuleValue, double oldRuleValue) const = 0;
 206
 207     /**
 208      * Calculates an upper bound when searching for a rule that matches
 209      * this substitution.  Rules with base values greater than or equal
 210      * to upperBound are not considered.
 211      * @param oldUpperBound    The current upper-bound setting.  The new
 212      *                         upper bound can't be any higher.
 213      * @return                 the upper bound when searching for a rule that matches
 214      *                         this substitution.
 215      */
 216     virtual double calcUpperBound(double oldUpperBound) const = 0;
 217
 218     //-----------------------------------------------------------------------
 219     // simple accessors
 220     //-----------------------------------------------------------------------
 221
 222     /**
 223      * Returns the substitution's position in the rule that owns it.
 224      * @return The substitution's position in the rule that owns it.
 225      */
 226     int32_t getPos() const { return pos; }
 227
 228     /**
 229      * Returns the character used in the textual representation of
 230      * substitutions of this type.  Used by toString().
 231      * @return This substitution's token character.
 232      */
 233     virtual UChar tokenChar() const = 0;
 234
 235     /**
 236      * Returns true if this is a null substitution.  (We didn't do this
 237      * with instanceof partially because it causes source files to
 238      * proliferate and partially because we have to port this to C++.)
 239      * @return true if this object is an instance of NullSubstitution
 240      */
 241     virtual UBool isNullSubstitution() const;
 242
 243     /**
 244      * Returns true if this is a modulus substitution.  (We didn't do this
 245      * with instanceof partially because it causes source files to
 246      * proliferate and partially because we have to port this to C++.)
 247      * @return true if this object is an instance of ModulusSubstitution
 248      */
 249     virtual UBool isModulusSubstitution() const;
 250
 251 private:
 252     NFSubstitution(const NFSubstitution &other); // forbid copying of this class
 253     NFSubstitution &operator=(const NFSubstitution &other); // forbid copying of this class
 254
 255 public:
 256     static UClassID getStaticClassID(void);
 257     virtual UClassID getDynamicClassID(void) const;
 258 };
 259
 260 U_NAMESPACE_END
 261
 262 /* U_HAVE_RBNF */
 263 #endif
 264
 265 // NFSUBS_H
 266 #endif