1 // Copyright (C) 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
4 ********************************************************************************
5 * Copyright (C) 2015, International Business Machines
6 * Corporation and others. All Rights Reserved.
7 ********************************************************************************
10 ********************************************************************************
13 #ifndef DECIMFMTIMPL_H
14 #define DECIMFMTIMPL_H
16 #include "unicode/utypes.h"
18 #if !UCONFIG_NO_FORMATTING
20 #include "unicode/decimfmt.h"
21 #include "unicode/uobject.h"
22 #include "affixpatternparser.h"
23 #include "digitaffixesandpadding.h"
24 #include "digitformatter.h"
25 #include "digitgrouping.h"
26 #include "precision.h"
33 class FieldPositionHandler;
37 * DecimalFormatImpl is the glue code between the legacy DecimalFormat class
38 * and the new decimal formatting classes. DecimalFormat still handles
39 * parsing directly. However, DecimalFormat uses attributes of this class
40 * for parsing when possible.
42 * The public API of this class closely mirrors the legacy API of the
43 * legacy DecimalFormat deviating only when the legacy API does not make
44 * sense. For example, although DecimalFormat has a
45 * getPadCharacterString() method, DecimalFormatImpl has a getPadCharacter()
46 * method because formatting uses only a single pad character for padding.
48 * Each legacy DecimalFormat instance heap allocates its own instance of
49 * this class. Most DecimalFormat methods that deal with formatting simply
50 * delegate to the DecimalFormat's DecimalFormatImpl method.
52 * Because DecimalFormat extends NumberFormat, Each instance of this class
53 * "borrows" a pointer to the NumberFormat part of its enclosing DecimalFormat
54 * instance. This way each DecimalFormatImpl instance can read or even modify
55 * the NumberFormat portion of its enclosing DecimalFormat instance.
57 * Directed acyclic graph (DAG):
59 * This class can be represented as a directed acyclic graph (DAG) where each
60 * vertex is an attribute, and each directed edge indicates that the value
61 * of the destination attribute is calculated from the value of the source
62 * attribute. Attributes with setter methods reside at the bottom of the
63 * DAG. That is, no edges point to them. We call these independent attributes
64 * because their values can be set independently of one another. The rest of
65 * the attributes are derived attributes because their values depend on the
66 * independent attributes. DecimalFormatImpl often uses the derived
67 * attributes, not the independent attributes, when formatting numbers.
69 * The independent attributes at the bottom of the DAG correspond to the legacy
70 * attributes of DecimalFormat while the attributes at the top of the DAG
71 * correspond to the attributes of the new code. The edges of the DAG
72 * correspond to the code that handles the complex interaction among all the
73 * legacy attributes of the DecimalFormat API.
75 * We use a DAG for three reasons.
77 * First, the DAG preserves backward compatibility. Clients of the legacy
78 * DecimalFormat expect existing getters and setters of each attribute to be
79 * consistent. That means if a client sets a particular attribute to a new
80 * value, the attribute should retain that value until the client sets it to
81 * a new value. The DAG allows these attributes to remain consistent even
82 * though the new code may not use them when formatting.
84 * Second, the DAG obviates the need to recalculate derived attributes with
85 * each format. Instead, the DAG "remembers" the values of all derived
86 * attributes. Only setting an independent attribute requires a recalculation.
87 * Moreover, setting an independent attribute recalculates only the affected
88 * dependent attributes rather than all dependent attributes.
90 * Third, the DAG abstracts away the complex interaction among the legacy
91 * attributes of the DecimalFormat API.
93 * Only the independent attributes of the DAG have setters and getters.
94 * Derived attributes have no setters (and often no getters either).
98 * For copy and assign, DecimalFormatImpl copies and assigns every attribute
99 * regardless of whether or not it is independent. We do this for simplicity.
101 * Implementation of the DAG:
103 * The DAG consists of three smaller DAGs:
104 * 1. Grouping attributes
105 * 2. Precision attributes
106 * 3. Formatting attributes.
108 * The first two DAGs are simple in that setting any independent attribute
109 * in the DAG recalculates all the dependent attributes in that DAG.
110 * The updateGrouping() and updatePrecision() perform the respective
113 * Because some of the derived formatting attributes are expensive to
114 * calculate, the formatting attributes DAG is more complex. The
115 * updateFormatting() method is composed of many updateFormattingXXX()
116 * methods, each of which recalculates a single derived attribute. The
117 * updateFormatting() method accepts a bitfield of recently changed
118 * attributes and passes this bitfield by reference to each of the
119 * updateFormattingXXX() methods. Each updateFormattingXXX() method checks
120 * the bitfield to see if any of the attributes it uses to compute the XXX
121 * attribute changed. If none of them changed, it exists immediately. However,
122 * if at least one of them changed, it recalculates the XXX attribute and
123 * sets the corresponding bit in the bitfield. In this way, each
124 * updateFormattingXXX() method encodes the directed edges in the formatting
125 * DAG that point to the attribute its calculating.
127 * Maintenance of the updateFormatting() method.
129 * Use care when changing the updateFormatting() method.
130 * The updateFormatting() method must call each updateFormattingXXX() in the
131 * same partial order that the formatting DAG prescribes. That is, the
132 * attributes near the bottom of the DAG must be calculated before attributes
133 * further up. As we mentioned in the prvious paragraph, the directed edges of
134 * the formatting DAG are encoded within each updateFormattingXXX() method.
135 * Finally, adding new attributes may involve adding to the bitmap that the
136 * updateFormatting() method uses. The top most attributes in the DAG,
137 * those that do not point to any attributes but only have attributes
138 * pointing to it, need not have a slot in the bitmap.
140 * Keep in mind that most of the code that makes the legacy DecimalFormat API
141 * work the way it always has before can be found in these various updateXXX()
142 * methods. For example the updatePrecisionForScientific() method
143 * handles the complex interactions amoung the various precision attributes
144 * when formatting in scientific notation. Changing the way attributes
145 * interract, often means changing one of these updateXXX() methods.
149 * The DecimFmtImpl class is the glue code between the legacy and new
150 * number formatting code. It uses a direct acyclic graph (DAG) to
151 * maintain backward compatibility, to make the code efficient, and to
152 * abstract away the complex interraction among legacy attributs.
156 class DecimalFormatImpl : public UObject {
161 const Locale &locale,
162 const UnicodeString &pattern,
166 const UnicodeString &pattern,
167 DecimalFormatSymbols *symbolsToAdopt,
168 UParseError &parseError,
172 const DecimalFormatImpl &other,
174 DecimalFormatImpl &assign(
175 const DecimalFormatImpl &other, UErrorCode &status);
176 virtual ~DecimalFormatImpl();
177 void adoptDecimalFormatSymbols(DecimalFormatSymbols *symbolsToAdopt);
178 const DecimalFormatSymbols &getDecimalFormatSymbols() const {
181 UnicodeString &format(
183 UnicodeString &appendTo,
185 UErrorCode &status) const;
186 UnicodeString &format(
188 UnicodeString &appendTo,
189 FieldPositionIterator *posIter,
190 UErrorCode &status) const;
191 UnicodeString &format(
193 UnicodeString &appendTo,
195 UErrorCode &status) const;
196 UnicodeString &format(
198 UnicodeString &appendTo,
200 UErrorCode &status) const;
201 UnicodeString &format(
202 const DigitList &number,
203 UnicodeString &appendTo,
205 UErrorCode &status) const;
206 UnicodeString &format(
208 UnicodeString &appendTo,
209 FieldPositionIterator *posIter,
210 UErrorCode &status) const;
211 UnicodeString &format(
213 UnicodeString &appendTo,
214 FieldPositionIterator *posIter,
215 UErrorCode &status) const;
216 UnicodeString &format(
217 const DigitList &number,
218 UnicodeString &appendTo,
219 FieldPositionIterator *posIter,
220 UErrorCode &status) const;
221 UnicodeString &format(
223 UnicodeString &appendTo,
224 FieldPositionIterator *posIter,
225 UErrorCode &status) const;
226 UnicodeString &format(
227 const VisibleDigitsWithExponent &digits,
228 UnicodeString &appendTo,
230 UErrorCode &status) const;
231 UnicodeString &format(
232 const VisibleDigitsWithExponent &digits,
233 UnicodeString &appendTo,
234 FieldPositionIterator *posIter,
235 UErrorCode &status) const;
237 UBool operator==(const DecimalFormatImpl &) const;
239 UBool operator!=(const DecimalFormatImpl &other) const {
240 return !(*this == other);
243 void setRoundingMode(DecimalFormat::ERoundingMode mode) {
244 fRoundingMode = mode;
245 fEffPrecision.fMantissa.fExactOnly = (fRoundingMode == DecimalFormat::kRoundUnnecessary);
246 fEffPrecision.fMantissa.fRoundingMode = mode;
248 DecimalFormat::ERoundingMode getRoundingMode() const {
249 return fRoundingMode;
251 void setFailIfMoreThanMaxDigits(UBool b) {
252 fEffPrecision.fMantissa.fFailIfOverMax = b;
254 UBool isFailIfMoreThanMaxDigits() const { return fEffPrecision.fMantissa.fFailIfOverMax; }
255 void setMinimumSignificantDigits(int32_t newValue);
256 void setMaximumSignificantDigits(int32_t newValue);
257 void setMinMaxSignificantDigits(int32_t min, int32_t max);
258 void setScientificNotation(UBool newValue);
259 void setSignificantDigitsUsed(UBool newValue);
261 int32_t getMinimumSignificantDigits() const {
262 return fMinSigDigits; }
263 int32_t getMaximumSignificantDigits() const {
264 return fMaxSigDigits; }
265 UBool isScientificNotation() const { return fUseScientific; }
266 UBool areSignificantDigitsUsed() const { return fUseSigDigits; }
267 void setGroupingSize(int32_t newValue);
268 void setSecondaryGroupingSize(int32_t newValue);
269 void setMinimumGroupingDigits(int32_t newValue);
270 int32_t getGroupingSize() const { return fGrouping.fGrouping; }
271 int32_t getSecondaryGroupingSize() const { return fGrouping.fGrouping2; }
272 int32_t getMinimumGroupingDigits() const { return fGrouping.fMinGrouping; }
273 void applyPattern(const UnicodeString &pattern, UErrorCode &status);
274 void applyPatternFavorCurrencyPrecision(
275 const UnicodeString &pattern, UErrorCode &status);
277 const UnicodeString &pattern, UParseError &perror, UErrorCode &status);
278 void applyLocalizedPattern(const UnicodeString &pattern, UErrorCode &status);
279 void applyLocalizedPattern(
280 const UnicodeString &pattern, UParseError &perror, UErrorCode &status);
281 void setCurrencyUsage(UCurrencyUsage usage, UErrorCode &status);
282 UCurrencyUsage getCurrencyUsage() const { return fCurrencyUsage; }
283 void setRoundingIncrement(double d);
284 double getRoundingIncrement() const;
285 int32_t getMultiplier() const;
286 void setMultiplier(int32_t m);
287 UChar32 getPadCharacter() const { return fAffixes.fPadChar; }
288 void setPadCharacter(UChar32 c) { fAffixes.fPadChar = c; }
289 int32_t getFormatWidth() const { return fAffixes.fWidth; }
290 void setFormatWidth(int32_t x) { fAffixes.fWidth = x; }
291 DigitAffixesAndPadding::EPadPosition getPadPosition() const {
292 return fAffixes.fPadPosition;
294 void setPadPosition(DigitAffixesAndPadding::EPadPosition x) {
295 fAffixes.fPadPosition = x;
297 int32_t getMinimumExponentDigits() const {
298 return fEffPrecision.fMinExponentDigits;
300 void setMinimumExponentDigits(int32_t x) {
301 fEffPrecision.fMinExponentDigits = x;
303 UBool isExponentSignAlwaysShown() const {
304 return fOptions.fExponent.fAlwaysShowSign;
306 void setExponentSignAlwaysShown(UBool x) {
307 fOptions.fExponent.fAlwaysShowSign = x;
309 UBool isDecimalSeparatorAlwaysShown() const {
310 return fOptions.fMantissa.fAlwaysShowDecimal;
312 void setDecimalSeparatorAlwaysShown(UBool x) {
313 fOptions.fMantissa.fAlwaysShowDecimal = x;
315 UnicodeString &getPositivePrefix(UnicodeString &result) const;
316 UnicodeString &getPositiveSuffix(UnicodeString &result) const;
317 UnicodeString &getNegativePrefix(UnicodeString &result) const;
318 UnicodeString &getNegativeSuffix(UnicodeString &result) const;
319 void setPositivePrefix(const UnicodeString &str);
320 void setPositiveSuffix(const UnicodeString &str);
321 void setNegativePrefix(const UnicodeString &str);
322 void setNegativeSuffix(const UnicodeString &str);
323 UnicodeString &toPattern(UnicodeString& result) const;
324 FixedDecimal &getFixedDecimal(double value, FixedDecimal &result, UErrorCode &status) const;
325 FixedDecimal &getFixedDecimal(DigitList &number, FixedDecimal &result, UErrorCode &status) const;
326 DigitList &round(DigitList &number, UErrorCode &status) const;
328 VisibleDigitsWithExponent &
329 initVisibleDigitsWithExponent(
331 VisibleDigitsWithExponent &digits,
332 UErrorCode &status) const;
333 VisibleDigitsWithExponent &
334 initVisibleDigitsWithExponent(
336 VisibleDigitsWithExponent &digits,
337 UErrorCode &status) const;
338 VisibleDigitsWithExponent &
339 initVisibleDigitsWithExponent(
341 VisibleDigitsWithExponent &digits,
342 UErrorCode &status) const;
344 void updatePrecision();
345 void updateGrouping();
346 void updateCurrency(UErrorCode &status);
350 // Disallow copy and assign
351 DecimalFormatImpl(const DecimalFormatImpl &other);
352 DecimalFormatImpl &operator=(const DecimalFormatImpl &other);
353 NumberFormat *fSuper;
354 DigitList fMultiplier;
357 DecimalFormat::ERoundingMode fRoundingMode;
359 // These fields include what the user can see and set.
360 // When the user updates these fields, it triggers automatic updates of
361 // other fields that may be invisible to user
363 // Updating any of the following fields triggers an update to
364 // fEffPrecision.fMantissa.fMin,
365 // fEffPrecision.fMantissa.fMax,
366 // fEffPrecision.fMantissa.fSignificant fields
367 // We have this two phase update because of backward compatibility.
368 // DecimalFormat has to remember all settings even if those settings are
369 // invalid or disabled.
370 int32_t fMinSigDigits;
371 int32_t fMaxSigDigits;
372 UBool fUseScientific;
374 // In addition to these listed above, changes to min/max int digits and
375 // min/max frac digits from fSuper also trigger an update.
377 // Updating any of the following fields triggers an update to
378 // fEffGrouping field Again we do it this way because original
379 // grouping settings have to be retained if grouping is turned off.
380 DigitGrouping fGrouping;
381 // In addition to these listed above, changes to isGroupingUsed in
382 // fSuper also triggers an update to fEffGrouping.
384 // Updating any of the following fields triggers updates on the following:
385 // fMonetary, fRules, fAffixParser, fCurrencyAffixInfo,
386 // fFormatter, fAffixes.fPositivePrefiix, fAffixes.fPositiveSuffix,
387 // fAffixes.fNegativePrefiix, fAffixes.fNegativeSuffix
388 // We do this two phase update because localizing the affix patterns
389 // and formatters can be expensive. Better to do it once with the setters
390 // than each time within format.
391 AffixPattern fPositivePrefixPattern;
392 AffixPattern fNegativePrefixPattern;
393 AffixPattern fPositiveSuffixPattern;
394 AffixPattern fNegativeSuffixPattern;
395 DecimalFormatSymbols *fSymbols;
396 UCurrencyUsage fCurrencyUsage;
397 // In addition to these listed above, changes to getCurrency() in
398 // fSuper also triggers an update.
400 // Optional may be NULL
403 // These fields are totally hidden from user and are used to derive the affixes
404 // in fAffixes below from the four affix patterns above.
406 AffixPatternParser fAffixParser;
407 CurrencyAffixInfo fCurrencyAffixInfo;
409 // The actual precision used when formatting
410 ScientificPrecision fEffPrecision;
412 // The actual grouping used when formatting
413 DigitGrouping fEffGrouping;
414 SciFormatterOptions fOptions; // Encapsulates fixed precision options
415 DigitFormatter fFormatter;
416 DigitAffixesAndPadding fAffixes;
418 UnicodeString &formatInt32(
420 UnicodeString &appendTo,
421 FieldPositionHandler &handler,
422 UErrorCode &status) const;
424 UnicodeString &formatInt64(
426 UnicodeString &appendTo,
427 FieldPositionHandler &handler,
428 UErrorCode &status) const;
430 UnicodeString &formatDouble(
432 UnicodeString &appendTo,
433 FieldPositionHandler &handler,
434 UErrorCode &status) const;
436 // Scales for precent or permille symbols
437 UnicodeString &formatDigitList(
439 UnicodeString &appendTo,
440 FieldPositionHandler &handler,
441 UErrorCode &status) const;
443 // Does not scale for precent or permille symbols
444 UnicodeString &formatAdjustedDigitList(
446 UnicodeString &appendTo,
447 FieldPositionHandler &handler,
448 UErrorCode &status) const;
450 UnicodeString &formatVisibleDigitsWithExponent(
451 const VisibleDigitsWithExponent &number,
452 UnicodeString &appendTo,
453 FieldPositionHandler &handler,
454 UErrorCode &status) const;
456 VisibleDigitsWithExponent &
457 initVisibleDigitsFromAdjusted(
459 VisibleDigitsWithExponent &digits,
460 UErrorCode &status) const;
463 UBool maybeFormatWithDigitList(
465 UnicodeString &appendTo,
466 FieldPositionHandler &handler,
467 UErrorCode &status) const;
470 UBool maybeInitVisibleDigitsFromDigitList(
472 VisibleDigitsWithExponent &digits,
473 UErrorCode &status) const;
475 DigitList &adjustDigitList(DigitList &number, UErrorCode &status) const;
478 const UnicodeString &pattern,
479 UBool localized, UParseError &perror, UErrorCode &status);
481 ValueFormatter &prepareValueFormatter(ValueFormatter &vf) const;
482 void setMultiplierScale(int32_t s);
483 int32_t getPatternScale() const;
484 void setScale(int32_t s) { fScale = s; }
485 int32_t getScale() const { return fScale; }
487 // Updates everything
488 void updateAll(UErrorCode &status);
490 int32_t formattingFlags,
491 UBool updatePrecisionBasedOnCurrency,
494 // Updates from formatting pattern changes
495 void updateForApplyPattern(UErrorCode &status);
496 void updateForApplyPatternFavorCurrencyPrecision(UErrorCode &status);
498 // Updates from changes to third group of attributes
499 void updateFormatting(int32_t changedFormattingFields, UErrorCode &status);
500 void updateFormatting(
501 int32_t changedFormattingFields,
502 UBool updatePrecisionBasedOnCurrency,
505 // Helper functions for updatePrecision
506 void updatePrecisionForScientific();
507 void updatePrecisionForFixed();
508 void extractMinMaxDigits(DigitInterval &min, DigitInterval &max) const;
509 void extractSigDigits(SignificantDigitInterval &sig) const;
511 // Helper functions for updateFormatting
512 void updateFormattingUsesCurrency(int32_t &changedFormattingFields);
513 void updateFormattingPluralRules(
514 int32_t &changedFormattingFields, UErrorCode &status);
515 void updateFormattingAffixParser(int32_t &changedFormattingFields);
516 void updateFormattingCurrencyAffixInfo(
517 int32_t &changedFormattingFields,
518 UBool updatePrecisionBasedOnCurrency,
520 void updateFormattingFixedPointFormatter(
521 int32_t &changedFormattingFields);
522 void updateFormattingLocalizedPositivePrefix(
523 int32_t &changedFormattingFields, UErrorCode &status);
524 void updateFormattingLocalizedPositiveSuffix(
525 int32_t &changedFormattingFields, UErrorCode &status);
526 void updateFormattingLocalizedNegativePrefix(
527 int32_t &changedFormattingFields, UErrorCode &status);
528 void updateFormattingLocalizedNegativeSuffix(
529 int32_t &changedFormattingFields, UErrorCode &status);
531 int32_t computeExponentPatternLength() const;
532 int32_t countFractionDigitAndDecimalPatternLength(int32_t fracDigitCount) const;
533 UnicodeString &toNumberPattern(
534 UBool hasPadding, int32_t minimumLength, UnicodeString& result) const;
536 int32_t getOldFormatWidth() const;
537 const UnicodeString &getConstSymbol(
538 DecimalFormatSymbols::ENumberFormatSymbol symbol) const;
539 UBool isParseFastpath() const;
541 friend class DecimalFormat;
547 #endif /* #if !UCONFIG_NO_FORMATTING */
548 #endif // DECIMFMTIMPL_H