mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-05 08:35:26 +00:00
284 lines
10 KiB
C++
284 lines
10 KiB
C++
/*
|
|
*****************************************************************************************
|
|
* *
|
|
* COPYRIGHT: *
|
|
* (C) Copyright Taligent, Inc., 1997 *
|
|
* (C) Copyright International Business Machines Corporation, 1997 *
|
|
* Licensed Material - Program-Property of IBM - All Rights Reserved. *
|
|
* US Government Users Restricted Rights - Use, duplication, or disclosure *
|
|
* restricted by GSA ADP Schedule Contract with IBM Corp. *
|
|
* *
|
|
*****************************************************************************************
|
|
*
|
|
* 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
|
|
*****************************************************************************************
|
|
*/
|
|
|
|
#ifndef _BRKITER
|
|
#define _BRKITER
|
|
|
|
#include "unistring.h"
|
|
#include "locid.h"
|
|
class Locale;
|
|
|
|
/**
|
|
* 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>
|
|
* This is the interface for all text boundaries.
|
|
* <P>
|
|
* Examples:
|
|
* <P>
|
|
* Print each element in order:
|
|
* <pre>
|
|
* . void printEachForward(const BreakIterator& boundary) {
|
|
* . UnicodeString textChunk;
|
|
* . TextOffset start = boundary.first();
|
|
* . for (TextOffset end = boundary.next();
|
|
* . end != BreakIterator::DONE;
|
|
* . start = end, end = boundary.next())
|
|
* . {
|
|
* . cout << boundary.getText()->extract(start, end, textChunk);
|
|
* . }
|
|
* . }
|
|
* </pre>
|
|
* Print each element in reverse order:
|
|
* <pre>
|
|
* . void printEachbackward(const BreakIterator& boundary) {
|
|
* . UnicodeString textChunk;
|
|
* . TextOffset end = boundary.last();
|
|
* . for (TextOffset start = boundary.previous();
|
|
* . start != BreakIterator::DONE;
|
|
* . end = start, start = boundary.previous())
|
|
* . {
|
|
* . cout << boundary.getText()->extract(start, end, textChunk);
|
|
* . }
|
|
* . }
|
|
* </pre>
|
|
*/
|
|
class T_FINDWORD_API BreakIterator {
|
|
public:
|
|
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.
|
|
*/
|
|
virtual t_bool operator==(const BreakIterator&) const = 0;
|
|
|
|
t_bool operator!=(const BreakIterator& rhs) const { return !operator==(rhs); }
|
|
|
|
/**
|
|
* Return a polymorphic copy of this object. This is an abstract
|
|
* method which subclasses implement.
|
|
*/
|
|
virtual BreakIterator* clone() const = 0;
|
|
|
|
/**
|
|
* Return a polymorphic class ID for this object. Different subclasses
|
|
* will return distinct unequal values.
|
|
*/
|
|
virtual ClassID getDynamicClassID() const = 0;
|
|
|
|
/**
|
|
* Get the text for which this object is finding the boundaries.
|
|
*/
|
|
virtual const UnicodeString* getText() const = 0;
|
|
|
|
/**
|
|
* Set the text for which this object should find the boundaries.
|
|
*/
|
|
virtual void setText(const UnicodeString*) = 0;
|
|
|
|
/**
|
|
* DONE is returned by previous() and next() after all valid
|
|
* boundaries have been returned.
|
|
*/
|
|
static const TextOffset DONE;
|
|
|
|
/**
|
|
* Return the index of the first character in the text being scanned.
|
|
*/
|
|
virtual TextOffset first() = 0;
|
|
|
|
/**
|
|
* Return the index immediately BEYOND the last character in the text being scanned.
|
|
*/
|
|
virtual TextOffset last() = 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.
|
|
*/
|
|
virtual TextOffset previous() = 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.
|
|
*/
|
|
virtual TextOffset next() = 0;
|
|
|
|
/**
|
|
* Return character index of the text boundary that was most recently
|
|
* returned by next(), previous(), first(), or last()
|
|
* @return The boundary most recently returned.
|
|
*/
|
|
virtual TextOffset current() 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.
|
|
*/
|
|
virtual TextOffset following(TextOffset 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.
|
|
*/
|
|
virtual TextOffset next(t_int32 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. If a specific WordBreak is not
|
|
* avaliable for the specified locale, a default WordBreak is returned.
|
|
* @return A BreakIterator for word-breaks
|
|
*/
|
|
static BreakIterator* createWordInstance(const Locale& where = Locale::getDefault());
|
|
|
|
/**
|
|
* 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. If a specific LineBreak is not
|
|
* avaliable for the specified locale, a default LineBreak is returned.
|
|
* @return A BreakIterator for line-breaks
|
|
*/
|
|
static BreakIterator* createLineInstance(const Locale& where = Locale::getDefault());
|
|
|
|
/**
|
|
* 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. If a specific character break is not
|
|
* avaliable for the specified locale, a default character break is returned.
|
|
* @return A BreakIterator for character-breaks
|
|
*/
|
|
static BreakIterator* createCharacterInstance(const Locale& where = Locale::getDefault());
|
|
|
|
/**
|
|
* Create BreakIterator for sentence-breaks using specified locale
|
|
* Returns an instance of a BreakIterator implementing sentence breaks.
|
|
* @param where the locale. If a specific SentenceBreak is not
|
|
* avaliable for the specified locale, a default SentenceBreak is returned.
|
|
* @return A BreakIterator for sentence-breaks
|
|
*/
|
|
static BreakIterator* createSentenceInstance(const Locale& where = Locale::getDefault());
|
|
|
|
/**
|
|
* Get the set of Locales for which TextBoundaries are installed
|
|
* @param count the output parameter of number of elements in the locale list
|
|
* @return available locales
|
|
*/
|
|
static const Locale* getAvailableLocales(t_int32& 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
|
|
*/
|
|
static UnicodeString& 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
|
|
*/
|
|
static UnicodeString& getDisplayName(const Locale& objectLocale,
|
|
UnicodeString& name);
|
|
|
|
|
|
|
|
// begin deprecated api.
|
|
virtual TextOffset nextAfter(TextOffset offset) = 0;
|
|
virtual TextOffset nthFromCurrent(t_int32 n) = 0;
|
|
static BreakIterator* createWordBreak(const Locale& where = Locale::getDefault()) { return createWordInstance(); }
|
|
static BreakIterator* createLineBreak(const Locale& where = Locale::getDefault()) { return createLineInstance(); }
|
|
static BreakIterator* createCharacterBreak(const Locale& where = Locale::getDefault()) { return createCharacterInstance(); }
|
|
static BreakIterator* createSentenceBreak(const Locale& where = Locale::getDefault()) { return createSentenceInstance(); }
|
|
// end deprecated api.
|
|
|
|
protected:
|
|
BreakIterator();
|
|
|
|
private:
|
|
/**
|
|
* The copy constructor and assignment operator have no real implementation.
|
|
* They are provided to make the compiler happy. Do not call.
|
|
*/
|
|
BreakIterator& operator=(const BreakIterator& other) { return *this; }
|
|
BreakIterator (const BreakIterator& other) {}
|
|
};
|
|
|
|
#endif // _BRKITER
|
|
//eof
|