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/*
********************************************************************************
* Copyright (C) 1997-2007, 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.
*/
#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 snippits illustrating the use of the Break Iterator APIs
* are available in the ICU User Guide,
* http://icu-project.org/userguide/boundaryAnalysis.html
* 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 UBool 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
*/
UBool 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(void) 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 = 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 NULL, 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.
* @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.
*
* @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
};
/**
* Return the index of the first character in the text being scanned.
* @stable ICU 2.0
*/
virtual int32_t first(void) = 0;
/**
* Return the index immediately BEYOND the last character in the text being scanned.
* @stable ICU 2.0
*/
virtual int32_t last(void) = 0;
/**
* Return 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;
/**
* Return 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 interator position within the text.
* @return The boundary most recently returned.
* @stable ICU 2.0
*/
virtual int32_t current(void) const = 0;
/**
* Return 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;
/**
* Return 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 specfied 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;
/**
* Return the nth boundary from the current boundary
* @param n which boundary to return. A value of 0
* does nothing. Negative values move to previous boundaries
* and positive values move to later boundaries.
* @return The index of the nth boundary from the current position, or
* DONE if there are fewer than |n| boundaries in the specfied direction.
* @stable ICU 2.0
*/
virtual int32_t next(int32_t n) = 0;
/**
* 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);
/**
* 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 Word Boundary iterator.{@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.
* @stable ICU 2.1
*/
static BreakIterator* U_EXPORT2
createTitleInstance(const Locale& where, UErrorCode& status);
/**
* 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 langauge.
* @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 langauge 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);
/**
* 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 NULL 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
*
* @stable ICU 2.0
*/
virtual BreakIterator * createBufferClone(void *stackBuffer,
int32_t &BufferSize,
UErrorCode &status) = 0;
/**
* 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).
* @stable ICU 2.0
*/
inline UBool isBufferClone(void);
#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.
* @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.
* @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;
/** 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;
private:
static BreakIterator* buildInstance(const Locale& loc, const char *type, int32_t kind, 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:
/** @internal */
BreakIterator();
/** @internal */
UBool fBufferClone;
/** @internal */
BreakIterator (const BreakIterator &other) : UObject(other), fBufferClone(FALSE) {}
private:
/** @internal */
char actualLocale[ULOC_FULLNAME_CAPACITY];
char validLocale[ULOC_FULLNAME_CAPACITY];
/**
* The assignment operator has no real implementation.
* It's provided to make the compiler happy. Do not call.
*/
BreakIterator& operator=(const BreakIterator&);
};
inline UBool BreakIterator::isBufferClone()
{
return fBufferClone;
}
U_NAMESPACE_END
#endif /* #if !UCONFIG_NO_BREAK_ITERATION */
#endif // _BRKITER
//eof
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