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Diffstat (limited to 'intl/icu/source/common/unicode/brkiter.h')
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diff --git a/intl/icu/source/common/unicode/brkiter.h b/intl/icu/source/common/unicode/brkiter.h new file mode 100644 index 0000000000..108652799e --- /dev/null +++ b/intl/icu/source/common/unicode/brkiter.h @@ -0,0 +1,670 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +******************************************************************************** +* Copyright (C) 1997-2016, International Business Machines +* Corporation and others. All Rights Reserved. +******************************************************************************** +* +* File brkiter.h +* +* Modification History: +* +* Date Name Description +* 02/18/97 aliu Added typedef for TextCount. Made DONE const. +* 05/07/97 aliu Fixed DLL declaration. +* 07/09/97 jfitz Renamed BreakIterator and interface synced with JDK +* 08/11/98 helena Sync-up JDK1.2. +* 01/13/2000 helena Added UErrorCode parameter to createXXXInstance methods. +******************************************************************************** +*/ + +#ifndef BRKITER_H +#define BRKITER_H + +#include "unicode/utypes.h" + +/** + * \file + * \brief C++ API: Break Iterator. + */ + +#include "unicode/utypes.h" + +#if U_SHOW_CPLUSPLUS_API + +#if UCONFIG_NO_BREAK_ITERATION + +U_NAMESPACE_BEGIN + +/* + * Allow the declaration of APIs with pointers to BreakIterator + * even when break iteration is removed from the build. + */ +class BreakIterator; + +U_NAMESPACE_END + +#else + +#include "unicode/uobject.h" +#include "unicode/unistr.h" +#include "unicode/chariter.h" +#include "unicode/locid.h" +#include "unicode/ubrk.h" +#include "unicode/strenum.h" +#include "unicode/utext.h" +#include "unicode/umisc.h" + +U_NAMESPACE_BEGIN + +/** + * The BreakIterator class implements methods for finding the location + * of boundaries in text. BreakIterator is an abstract base class. + * Instances of BreakIterator maintain a current position and scan over + * text returning the index of characters where boundaries occur. + * <p> + * Line boundary analysis determines where a text string can be broken + * when line-wrapping. The mechanism correctly handles punctuation and + * hyphenated words. + * <p> + * Sentence boundary analysis allows selection with correct + * interpretation of periods within numbers and abbreviations, and + * trailing punctuation marks such as quotation marks and parentheses. + * <p> + * Word boundary analysis is used by search and replace functions, as + * well as within text editing applications that allow the user to + * select words with a double click. Word selection provides correct + * interpretation of punctuation marks within and following + * words. Characters that are not part of a word, such as symbols or + * punctuation marks, have word-breaks on both sides. + * <p> + * Character boundary analysis allows users to interact with + * characters as they expect to, for example, when moving the cursor + * through a text string. Character boundary analysis provides correct + * navigation of through character strings, regardless of how the + * character is stored. For example, an accented character might be + * stored as a base character and a diacritical mark. What users + * consider to be a character can differ between languages. + * <p> + * The text boundary positions are found according to the rules + * described in Unicode Standard Annex #29, Text Boundaries, and + * Unicode Standard Annex #14, Line Breaking Properties. These + * are available at http://www.unicode.org/reports/tr14/ and + * http://www.unicode.org/reports/tr29/. + * <p> + * In addition to the C++ API defined in this header file, a + * plain C API with equivalent functionality is defined in the + * file ubrk.h + * <p> + * Code snippets illustrating the use of the Break Iterator APIs + * are available in the ICU User Guide, + * https://unicode-org.github.io/icu/userguide/boundaryanalysis/ + * and in the sample program icu/source/samples/break/break.cpp + * + */ +class U_COMMON_API BreakIterator : public UObject { +public: + /** + * destructor + * @stable ICU 2.0 + */ + virtual ~BreakIterator(); + + /** + * Return true if another object is semantically equal to this + * one. The other object should be an instance of the same subclass of + * BreakIterator. Objects of different subclasses are considered + * unequal. + * <P> + * Return true if this BreakIterator is at the same position in the + * same text, and is the same class and type (word, line, etc.) of + * BreakIterator, as the argument. Text is considered the same if + * it contains the same characters, it need not be the same + * object, and styles are not considered. + * @stable ICU 2.0 + */ + virtual bool operator==(const BreakIterator&) const = 0; + + /** + * Returns the complement of the result of operator== + * @param rhs The BreakIterator to be compared for inequality + * @return the complement of the result of operator== + * @stable ICU 2.0 + */ + bool operator!=(const BreakIterator& rhs) const { return !operator==(rhs); } + + /** + * Return a polymorphic copy of this object. This is an abstract + * method which subclasses implement. + * @stable ICU 2.0 + */ + virtual BreakIterator* clone() const = 0; + + /** + * Return a polymorphic class ID for this object. Different subclasses + * will return distinct unequal values. + * @stable ICU 2.0 + */ + virtual UClassID getDynamicClassID(void) const override = 0; + + /** + * Return a CharacterIterator over the text being analyzed. + * @stable ICU 2.0 + */ + virtual CharacterIterator& getText(void) const = 0; + + + /** + * Get a UText for the text being analyzed. + * The returned UText is a shallow clone of the UText used internally + * by the break iterator implementation. It can safely be used to + * access the text without impacting any break iterator operations, + * but the underlying text itself must not be altered. + * + * @param fillIn A UText to be filled in. If nullptr, a new UText will be + * allocated to hold the result. + * @param status receives any error codes. + * @return The current UText for this break iterator. If an input + * UText was provided, it will always be returned. + * @stable ICU 3.4 + */ + virtual UText *getUText(UText *fillIn, UErrorCode &status) const = 0; + + /** + * Change the text over which this operates. The text boundary is + * reset to the start. + * + * The BreakIterator will retain a reference to the supplied string. + * The caller must not modify or delete the text while the BreakIterator + * retains the reference. + * + * @param text The UnicodeString used to change the text. + * @stable ICU 2.0 + */ + virtual void setText(const UnicodeString &text) = 0; + + /** + * Reset the break iterator to operate over the text represented by + * the UText. The iterator position is reset to the start. + * + * This function makes a shallow clone of the supplied UText. This means + * that the caller is free to immediately close or otherwise reuse the + * Utext that was passed as a parameter, but that the underlying text itself + * must not be altered while being referenced by the break iterator. + * + * All index positions returned by break iterator functions are + * native indices from the UText. For example, when breaking UTF-8 + * encoded text, the break positions returned by next(), previous(), etc. + * will be UTF-8 string indices, not UTF-16 positions. + * + * @param text The UText used to change the text. + * @param status receives any error codes. + * @stable ICU 3.4 + */ + virtual void setText(UText *text, UErrorCode &status) = 0; + + /** + * Change the text over which this operates. The text boundary is + * reset to the start. + * Note that setText(UText *) provides similar functionality to this function, + * and is more efficient. + * @param it The CharacterIterator used to change the text. + * @stable ICU 2.0 + */ + virtual void adoptText(CharacterIterator* it) = 0; + + enum { + /** + * DONE is returned by previous() and next() after all valid + * boundaries have been returned. + * @stable ICU 2.0 + */ + DONE = (int32_t)-1 + }; + + /** + * Sets the current iteration position to the beginning of the text, position zero. + * @return The offset of the beginning of the text, zero. + * @stable ICU 2.0 + */ + virtual int32_t first(void) = 0; + + /** + * Set the iterator position to the index immediately BEYOND the last character in the text being scanned. + * @return The index immediately BEYOND the last character in the text being scanned. + * @stable ICU 2.0 + */ + virtual int32_t last(void) = 0; + + /** + * Set the iterator position to the boundary preceding the current boundary. + * @return The character index of the previous text boundary or DONE if all + * boundaries have been returned. + * @stable ICU 2.0 + */ + virtual int32_t previous(void) = 0; + + /** + * Advance the iterator to the boundary following the current boundary. + * @return The character index of the next text boundary or DONE if all + * boundaries have been returned. + * @stable ICU 2.0 + */ + virtual int32_t next(void) = 0; + + /** + * Return character index of the current iterator position within the text. + * @return The boundary most recently returned. + * @stable ICU 2.0 + */ + virtual int32_t current(void) const = 0; + + /** + * Advance the iterator to the first boundary following the specified offset. + * The value returned is always greater than the offset or + * the value BreakIterator.DONE + * @param offset the offset to begin scanning. + * @return The first boundary after the specified offset. + * @stable ICU 2.0 + */ + virtual int32_t following(int32_t offset) = 0; + + /** + * Set the iterator position to the first boundary preceding the specified offset. + * The value returned is always smaller than the offset or + * the value BreakIterator.DONE + * @param offset the offset to begin scanning. + * @return The first boundary before the specified offset. + * @stable ICU 2.0 + */ + virtual int32_t preceding(int32_t offset) = 0; + + /** + * Return true if the specified position is a boundary position. + * As a side effect, the current position of the iterator is set + * to the first boundary position at or following the specified offset. + * @param offset the offset to check. + * @return True if "offset" is a boundary position. + * @stable ICU 2.0 + */ + virtual UBool isBoundary(int32_t offset) = 0; + + /** + * Set the iterator position to the nth boundary from the current boundary + * @param n the number of boundaries to move by. A value of 0 + * does nothing. Negative values move to previous boundaries + * and positive values move to later boundaries. + * @return The new iterator position, or + * DONE if there are fewer than |n| boundaries in the specified direction. + * @stable ICU 2.0 + */ + virtual int32_t next(int32_t n) = 0; + + /** + * For RuleBasedBreakIterators, return the status tag from the break rule + * that determined the boundary at the current iteration position. + * <p> + * For break iterator types that do not support a rule status, + * a default value of 0 is returned. + * <p> + * @return the status from the break rule that determined the boundary at + * the current iteration position. + * @see RuleBaseBreakIterator::getRuleStatus() + * @see UWordBreak + * @stable ICU 52 + */ + virtual int32_t getRuleStatus() const; + + /** + * For RuleBasedBreakIterators, get the status (tag) values from the break rule(s) + * that determined the boundary at the current iteration position. + * <p> + * For break iterator types that do not support rule status, + * no values are returned. + * <p> + * The returned status value(s) are stored into an array provided by the caller. + * The values are stored in sorted (ascending) order. + * If the capacity of the output array is insufficient to hold the data, + * the output will be truncated to the available length, and a + * U_BUFFER_OVERFLOW_ERROR will be signaled. + * <p> + * @see RuleBaseBreakIterator::getRuleStatusVec + * + * @param fillInVec an array to be filled in with the status values. + * @param capacity the length of the supplied vector. A length of zero causes + * the function to return the number of status values, in the + * normal way, without attempting to store any values. + * @param status receives error codes. + * @return The number of rule status values from rules that determined + * the boundary at the current iteration position. + * In the event of a U_BUFFER_OVERFLOW_ERROR, the return value + * is the total number of status values that were available, + * not the reduced number that were actually returned. + * @see getRuleStatus + * @stable ICU 52 + */ + virtual int32_t getRuleStatusVec(int32_t *fillInVec, int32_t capacity, UErrorCode &status); + + /** + * Create BreakIterator for word-breaks using the given locale. + * Returns an instance of a BreakIterator implementing word breaks. + * WordBreak is useful for word selection (ex. double click) + * @param where the locale. + * @param status the error code + * @return A BreakIterator for word-breaks. The UErrorCode& status + * parameter is used to return status information to the user. + * To check whether the construction succeeded or not, you should check + * the value of U_SUCCESS(err). If you wish more detailed information, you + * can check for informational error results which still indicate success. + * U_USING_FALLBACK_WARNING indicates that a fall back locale was used. For + * example, 'de_CH' was requested, but nothing was found there, so 'de' was + * used. U_USING_DEFAULT_WARNING indicates that the default locale data was + * used; neither the requested locale nor any of its fall back locales + * could be found. + * The caller owns the returned object and is responsible for deleting it. + * @stable ICU 2.0 + */ + static BreakIterator* U_EXPORT2 + createWordInstance(const Locale& where, UErrorCode& status); + + /** + * Create BreakIterator for line-breaks using specified locale. + * Returns an instance of a BreakIterator implementing line breaks. Line + * breaks are logically possible line breaks, actual line breaks are + * usually determined based on display width. + * LineBreak is useful for word wrapping text. + * @param where the locale. + * @param status The error code. + * @return A BreakIterator for line-breaks. The UErrorCode& status + * parameter is used to return status information to the user. + * To check whether the construction succeeded or not, you should check + * the value of U_SUCCESS(err). If you wish more detailed information, you + * can check for informational error results which still indicate success. + * U_USING_FALLBACK_WARNING indicates that a fall back locale was used. For + * example, 'de_CH' was requested, but nothing was found there, so 'de' was + * used. U_USING_DEFAULT_WARNING indicates that the default locale data was + * used; neither the requested locale nor any of its fall back locales + * could be found. + * The caller owns the returned object and is responsible for deleting it. + * @stable ICU 2.0 + */ + static BreakIterator* U_EXPORT2 + createLineInstance(const Locale& where, UErrorCode& status); + + /** + * Create BreakIterator for character-breaks using specified locale + * Returns an instance of a BreakIterator implementing character breaks. + * Character breaks are boundaries of combining character sequences. + * @param where the locale. + * @param status The error code. + * @return A BreakIterator for character-breaks. The UErrorCode& status + * parameter is used to return status information to the user. + * To check whether the construction succeeded or not, you should check + * the value of U_SUCCESS(err). If you wish more detailed information, you + * can check for informational error results which still indicate success. + * U_USING_FALLBACK_WARNING indicates that a fall back locale was used. For + * example, 'de_CH' was requested, but nothing was found there, so 'de' was + * used. U_USING_DEFAULT_WARNING indicates that the default locale data was + * used; neither the requested locale nor any of its fall back locales + * could be found. + * The caller owns the returned object and is responsible for deleting it. + * @stable ICU 2.0 + */ + static BreakIterator* U_EXPORT2 + createCharacterInstance(const Locale& where, UErrorCode& status); + + /** + * Create BreakIterator for sentence-breaks using specified locale + * Returns an instance of a BreakIterator implementing sentence breaks. + * @param where the locale. + * @param status The error code. + * @return A BreakIterator for sentence-breaks. The UErrorCode& status + * parameter is used to return status information to the user. + * To check whether the construction succeeded or not, you should check + * the value of U_SUCCESS(err). If you wish more detailed information, you + * can check for informational error results which still indicate success. + * U_USING_FALLBACK_WARNING indicates that a fall back locale was used. For + * example, 'de_CH' was requested, but nothing was found there, so 'de' was + * used. U_USING_DEFAULT_WARNING indicates that the default locale data was + * used; neither the requested locale nor any of its fall back locales + * could be found. + * The caller owns the returned object and is responsible for deleting it. + * @stable ICU 2.0 + */ + static BreakIterator* U_EXPORT2 + createSentenceInstance(const Locale& where, UErrorCode& status); + +#ifndef U_HIDE_DEPRECATED_API + /** + * Create BreakIterator for title-casing breaks using the specified locale + * Returns an instance of a BreakIterator implementing title breaks. + * The iterator returned locates title boundaries as described for + * Unicode 3.2 only. For Unicode 4.0 and above title boundary iteration, + * please use a word boundary iterator. See {@link #createWordInstance }. + * + * @param where the locale. + * @param status The error code. + * @return A BreakIterator for title-breaks. The UErrorCode& status + * parameter is used to return status information to the user. + * To check whether the construction succeeded or not, you should check + * the value of U_SUCCESS(err). If you wish more detailed information, you + * can check for informational error results which still indicate success. + * U_USING_FALLBACK_WARNING indicates that a fall back locale was used. For + * example, 'de_CH' was requested, but nothing was found there, so 'de' was + * used. U_USING_DEFAULT_WARNING indicates that the default locale data was + * used; neither the requested locale nor any of its fall back locales + * could be found. + * The caller owns the returned object and is responsible for deleting it. + * @deprecated ICU 64 Use createWordInstance instead. + */ + static BreakIterator* U_EXPORT2 + createTitleInstance(const Locale& where, UErrorCode& status); +#endif /* U_HIDE_DEPRECATED_API */ + + /** + * Get the set of Locales for which TextBoundaries are installed. + * <p><b>Note:</b> this will not return locales added through the register + * call. To see the registered locales too, use the getAvailableLocales + * function that returns a StringEnumeration object </p> + * @param count the output parameter of number of elements in the locale list + * @return available locales + * @stable ICU 2.0 + */ + static const Locale* U_EXPORT2 getAvailableLocales(int32_t& count); + + /** + * Get name of the object for the desired Locale, in the desired language. + * @param objectLocale must be from getAvailableLocales. + * @param displayLocale specifies the desired locale for output. + * @param name the fill-in parameter of the return value + * Uses best match. + * @return user-displayable name + * @stable ICU 2.0 + */ + static UnicodeString& U_EXPORT2 getDisplayName(const Locale& objectLocale, + const Locale& displayLocale, + UnicodeString& name); + + /** + * Get name of the object for the desired Locale, in the language of the + * default locale. + * @param objectLocale must be from getMatchingLocales + * @param name the fill-in parameter of the return value + * @return user-displayable name + * @stable ICU 2.0 + */ + static UnicodeString& U_EXPORT2 getDisplayName(const Locale& objectLocale, + UnicodeString& name); + +#ifndef U_FORCE_HIDE_DEPRECATED_API + /** + * Deprecated functionality. Use clone() instead. + * + * Thread safe client-buffer-based cloning operation + * Do NOT call delete on a safeclone, since 'new' is not used to create it. + * @param stackBuffer user allocated space for the new clone. If nullptr new memory will be allocated. + * If buffer is not large enough, new memory will be allocated. + * @param BufferSize reference to size of allocated space. + * If BufferSize == 0, a sufficient size for use in cloning will + * be returned ('pre-flighting') + * If BufferSize is not enough for a stack-based safe clone, + * new memory will be allocated. + * @param status to indicate whether the operation went on smoothly or there were errors + * An informational status value, U_SAFECLONE_ALLOCATED_ERROR, is used if any allocations were + * necessary. + * @return pointer to the new clone + * + * @deprecated ICU 52. Use clone() instead. + */ + virtual BreakIterator * createBufferClone(void *stackBuffer, + int32_t &BufferSize, + UErrorCode &status) = 0; +#endif // U_FORCE_HIDE_DEPRECATED_API + +#ifndef U_HIDE_DEPRECATED_API + + /** + * Determine whether the BreakIterator was created in user memory by + * createBufferClone(), and thus should not be deleted. Such objects + * must be closed by an explicit call to the destructor (not delete). + * @deprecated ICU 52. Always delete the BreakIterator. + */ + inline UBool isBufferClone(void); + +#endif /* U_HIDE_DEPRECATED_API */ + +#if !UCONFIG_NO_SERVICE + /** + * Register a new break iterator of the indicated kind, to use in the given locale. + * The break iterator will be adopted. Clones of the iterator will be returned + * if a request for a break iterator of the given kind matches or falls back to + * this locale. + * Because ICU may choose to cache BreakIterators internally, this must + * be called at application startup, prior to any calls to + * BreakIterator::createXXXInstance to avoid undefined behavior. + * @param toAdopt the BreakIterator instance to be adopted + * @param locale the Locale for which this instance is to be registered + * @param kind the type of iterator for which this instance is to be registered + * @param status the in/out status code, no special meanings are assigned + * @return a registry key that can be used to unregister this instance + * @stable ICU 2.4 + */ + static URegistryKey U_EXPORT2 registerInstance(BreakIterator* toAdopt, + const Locale& locale, + UBreakIteratorType kind, + UErrorCode& status); + + /** + * Unregister a previously-registered BreakIterator using the key returned from the + * register call. Key becomes invalid after a successful call and should not be used again. + * The BreakIterator corresponding to the key will be deleted. + * Because ICU may choose to cache BreakIterators internally, this should + * be called during application shutdown, after all calls to + * BreakIterator::createXXXInstance to avoid undefined behavior. + * @param key the registry key returned by a previous call to registerInstance + * @param status the in/out status code, no special meanings are assigned + * @return true if the iterator for the key was successfully unregistered + * @stable ICU 2.4 + */ + static UBool U_EXPORT2 unregister(URegistryKey key, UErrorCode& status); + + /** + * Return a StringEnumeration over the locales available at the time of the call, + * including registered locales. + * @return a StringEnumeration over the locales available at the time of the call + * @stable ICU 2.4 + */ + static StringEnumeration* U_EXPORT2 getAvailableLocales(void); +#endif + + /** + * Returns the locale for this break iterator. Two flavors are available: valid and + * actual locale. + * @stable ICU 2.8 + */ + Locale getLocale(ULocDataLocaleType type, UErrorCode& status) const; + +#ifndef U_HIDE_INTERNAL_API + /** Get the locale for this break iterator object. You can choose between valid and actual locale. + * @param type type of the locale we're looking for (valid or actual) + * @param status error code for the operation + * @return the locale + * @internal + */ + const char *getLocaleID(ULocDataLocaleType type, UErrorCode& status) const; +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Set the subject text string upon which the break iterator is operating + * without changing any other aspect of the matching state. + * The new and previous text strings must have the same content. + * + * This function is intended for use in environments where ICU is operating on + * strings that may move around in memory. It provides a mechanism for notifying + * ICU that the string has been relocated, and providing a new UText to access the + * string in its new position. + * + * Note that the break iterator implementation never copies the underlying text + * of a string being processed, but always operates directly on the original text + * provided by the user. Refreshing simply drops the references to the old text + * and replaces them with references to the new. + * + * Caution: this function is normally used only by very specialized, + * system-level code. One example use case is with garbage collection that moves + * the text in memory. + * + * @param input The new (moved) text string. + * @param status Receives errors detected by this function. + * @return *this + * + * @stable ICU 49 + */ + virtual BreakIterator &refreshInputText(UText *input, UErrorCode &status) = 0; + + private: + static BreakIterator* buildInstance(const Locale& loc, const char *type, UErrorCode& status); + static BreakIterator* createInstance(const Locale& loc, int32_t kind, UErrorCode& status); + static BreakIterator* makeInstance(const Locale& loc, int32_t kind, UErrorCode& status); + + friend class ICUBreakIteratorFactory; + friend class ICUBreakIteratorService; + +protected: + // Do not enclose protected default/copy constructors with #ifndef U_HIDE_INTERNAL_API + // or else the compiler will create a public ones. + /** @internal */ + BreakIterator(); + /** @internal */ + BreakIterator (const BreakIterator &other); +#ifndef U_HIDE_INTERNAL_API + /** @internal */ + BreakIterator (const Locale& valid, const Locale &actual); + /** @internal. Assignment Operator, used by RuleBasedBreakIterator. */ + BreakIterator &operator = (const BreakIterator &other); +#endif /* U_HIDE_INTERNAL_API */ + +private: + + /** @internal (private) */ + char actualLocale[ULOC_FULLNAME_CAPACITY]; + char validLocale[ULOC_FULLNAME_CAPACITY]; +}; + +#ifndef U_HIDE_DEPRECATED_API + +inline UBool BreakIterator::isBufferClone() +{ + return false; +} + +#endif /* U_HIDE_DEPRECATED_API */ + +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_BREAK_ITERATION */ + +#endif /* U_SHOW_CPLUSPLUS_API */ + +#endif // BRKITER_H +//eof |