#include <chariter.h>
Class diagram for CharacterIterator:
Public Members | |||
![]() | ![]() | enum | EOrigin { kStart, kCurrent, kEnd } |
![]() | ![]() | Origin enumeration for the move() and move32() functions. More... | |
![]() | ![]() | virtual CharacterIterator* | clone (void) const = 0 |
![]() | ![]() | Returns a pointer to a new CharacterIterator of the same concrete class as this one, and referring to the same character in the same text-storage object as this one. More... | |
![]() | ![]() | virtual UChar | first (void) = 0 |
![]() | ![]() | Sets the iterator to refer to the first code unit in its iteration range, and returns that code unit. More... | |
![]() | ![]() | virtual UChar | firstPostInc (void) |
![]() | ![]() | Sets the iterator to refer to the first code unit in its iteration range, returns that code unit, and moves the position to the second code unit. More... | |
![]() | ![]() | virtual UChar32 | first32 (void) = 0 |
![]() | ![]() | Sets the iterator to refer to the first code point in its iteration range, and returns that code unit, This can be used to begin an iteration with next32(). More... | |
![]() | ![]() | virtual UChar32 | first32PostInc (void) |
![]() | ![]() | Sets the iterator to refer to the first code point in its iteration range, returns that code point, and moves the position to the second code point. More... | |
![]() | ![]() | UTextOffset | setToStart () |
![]() | ![]() | Sets the iterator to refer to the first code unit or code point in its iteration range. More... | |
![]() | ![]() | virtual UChar | last (void) = 0 |
![]() | ![]() | Sets the iterator to refer to the last code unit in its iteration range, and returns that code unit. More... | |
![]() | ![]() | virtual UChar32 | last32 (void) = 0 |
![]() | ![]() | Sets the iterator to refer to the last code point in its iteration range, and returns that code unit. More... | |
![]() | ![]() | UTextOffset | setToEnd () |
![]() | ![]() | Sets the iterator to the end of its iteration range, just behind the last code unit or code point. More... | |
![]() | ![]() | virtual UChar | setIndex (UTextOffset position) = 0 |
![]() | ![]() | Sets the iterator to refer to the "position"-th code unit in the text-storage object the iterator refers to, and returns that code unit. More... | |
![]() | ![]() | virtual UChar32 | setIndex32 (UTextOffset position) = 0 |
![]() | ![]() | Sets the iterator to refer to the beginning of the code point that contains the "position"-th code unit in the text-storage object the iterator refers to, and returns that code point. More... | |
![]() | ![]() | virtual UChar | current (void) const = 0 |
![]() | ![]() | Returns the code unit the iterator currently refers to. More... | |
![]() | ![]() | virtual UChar32 | current32 (void) const = 0 |
![]() | ![]() | Returns the code point the iterator currently refers to. More... | |
![]() | ![]() | virtual UChar | next (void) = 0 |
![]() | ![]() | Advances to the next code unit in the iteration range (toward endIndex()), and returns that code unit. More... | |
![]() | ![]() | virtual UChar32 | next32 (void) = 0 |
![]() | ![]() | Advances to the next code point in the iteration range (toward endIndex()), and returns that code point. More... | |
![]() | ![]() | virtual UChar | previous (void) = 0 |
![]() | ![]() | Advances to the previous code unit in the iteration rance (toward startIndex()), and returns that code unit. More... | |
![]() | ![]() | virtual UChar32 | previous32 (void) = 0 |
![]() | ![]() | Advances to the previous code point in the iteration rance (toward startIndex()), and returns that code point. More... | |
![]() | ![]() | virtual UBool | hasPrevious () = 0 |
![]() | ![]() | Returns FALSE if there are no more code units or code points before the current position in the iteration range. More... | |
![]() | ![]() | UTextOffset | startIndex (void) const |
![]() | ![]() | Returns the numeric index in the underlying text-storage object of the character returned by first(). More... | |
![]() | ![]() | UTextOffset | endIndex (void) const |
![]() | ![]() | Returns the numeric index in the underlying text-storage object of the position immediately BEYOND the character returned by last(). More... | |
![]() | ![]() | UTextOffset | getIndex (void) const |
![]() | ![]() | Returns the numeric index in the underlying text-storage object of the character the iterator currently refers to (i.e., the character returned by current()). More... | |
![]() | ![]() | int32_t | getLength () const |
![]() | ![]() | Returns the length of the entire text in the underlying text-storage object. | |
![]() | ![]() | virtual UTextOffset | move (int32_t delta, EOrigin origin) = 0 |
![]() | ![]() | Moves the current position relative to the start or end of the iteration range, or relative to the current position itself. More... | |
![]() | ![]() | virtual UTextOffset | move32 (int32_t delta, EOrigin origin) = 0 |
![]() | ![]() | Moves the current position relative to the start or end of the iteration range, or relative to the current position itself. More... | |
![]() | ![]() | virtual void | getText (UnicodeString& result) = 0 |
![]() | ![]() | Copies the text under iteration into the UnicodeString referred to by "result". More... | |
Protected Members | |||
![]() | ![]() | CharacterIterator () | |
![]() | ![]() | CharacterIterator (int32_t length) | |
![]() | ![]() | CharacterIterator (int32_t length, UTextOffset position) | |
![]() | ![]() | CharacterIterator (int32_t length, UTextOffset begin, UTextOffset end, UTextOffset position) | |
![]() | ![]() | CharacterIterator (const CharacterIterator &that) | |
![]() | ![]() | CharacterIterator& | operator= (const CharacterIterator &that) |
![]() | ![]() | int32_t | textLength |
![]() | ![]() | UTextOffset | pos |
![]() | ![]() | UTextOffset | begin |
![]() | ![]() | UTextOffset | end |
This is an interface for forward and backward iteration and random access into a text object.
The API provides backward compatibility to the Java and older ICU CharacterIterator classes but extends them significantly:
See ForwardCharacterIterator for examples for using the new forward iteration functions. For backward iteration, there is also a hasPrevious() function that can be used analogously to hasNext(). The old functions work as before and are shown below.
Examples for some of the new functions:
Forward iteration with hasNext():   void forward1(CharacterIterator &it) {   UChar32 c;   for(it.setToStart(); it.hasNext();) {   c=it.next32PostInc();   // use c   }   }
Forward iteration more similar to loops with the old forward iteration, showing a way to convert simple for() loops:   void forward2(CharacterIterator &it) {   UChar c;   for(c=it.firstPostInc(); c!=CharacterIterator::DONE; c=it.nextPostInc()) {   // use c   }   }
Backward iteration with setToEnd() and hasPrevious():   void backward1(CharacterIterator &it) {   UChar32 c;   for(it.setToEnd(); it.hasPrevious();) {   c=it.previous32();   // use c   }   }
Backward iteration with a more traditional for() loop:   void backward2(CharacterIterator &it) {   UChar c;   for(c=it.last(); c!=CharacterIterator::DONE; c=it.previous()) {   // use c   }   }
Example for random access:   void random(CharacterIterator &it) {   // set to the third code point from the beginning   it.move32(3, CharacterIterator::kStart);   // get a code point from here without moving the position   UChar32 c=it.current32();   // get the position   int32_t pos=it.getIndex();   // get the previous code unit   UChar u=it.previous();   // move back one more code unit   it.move(-1, CharacterIterator::kCurrent);   // set the position back to where it was   // and read the same code point c and move beyond it   it.setIndex(pos);   if(c!=it.next32PostInc()) {   exit(1); // CharacterIterator inconsistent   }   }
Examples, especially for the old API:
Function processing characters, in this example simple output
  void processChar( UChar c )   {   cout << " " << c;   }
  void traverseForward(CharacterIterator& iter)   {   for(UChar c = iter.first(); c != CharacterIterator.DONE; c = iter.next()) {   processChar(c);   }   }
  void traverseBackward(CharacterIterator& iter)   {   for(UChar c = iter.last(); c != CharacterIterator.DONE; c = iter.previous()) {   processChar(c);   }   }
  void traverseOut(CharacterIterator& iter, UTextOffset pos)   {   UChar c;   for (c = iter.setIndex(pos);   c != CharacterIterator.DONE && (Unicode::isLetter(c) || Unicode::isDigit(c));   c = iter.next()) {}   UTextOffset end = iter.getIndex();   for (c = iter.setIndex(pos);   c != CharacterIterator.DONE && (Unicode::isLetter(c) || Unicode::isDigit(c));   c = iter.previous()) {}   UTextOffset start = iter.getIndex() + 1;     cout << "start: " << start << " end: " << end << endl;   for (c = iter.setIndex(start); iter.getIndex() < end; c = iter.next() ) {   processChar(c);   }   }
  void CharacterIterator_Example( void )   {   cout << endl << "===== CharacterIterator_Example: =====" << endl;   UnicodeString text("Ein kleiner Satz.");   StringCharacterIterator iterator(text);   cout << "----- traverseForward: -----------" << endl;   traverseForward( iterator );   cout << endl << endl << "----- traverseBackward: ----------" << endl;   traverseBackward( iterator );   cout << endl << endl << "----- traverseOut: ---------------" << endl;   traverseOut( iterator, 7 );   cout << endl << endl << "-----" << endl;   }
Definition at line 304 of file chariter.h.
enum CharacterIterator::EOrigin |
Origin enumeration for the move() and move32() functions.
Definition at line 309 of file chariter.h.
virtual CharacterIterator * CharacterIterator::clone (void) const [pure virtual]
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Returns a pointer to a new CharacterIterator of the same concrete class as this one, and referring to the same character in the same text-storage object as this one.
The caller is responsible for deleting the new clone.
Reimplemented in StringCharacterIterator, and UCharCharacterIterator.
virtual UChar CharacterIterator::first (void) [pure virtual]
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Sets the iterator to refer to the first code unit in its iteration range, and returns that code unit.
This can be used to begin an iteration with next().
Reimplemented in UCharCharacterIterator.
virtual UChar CharacterIterator::firstPostInc (void) [virtual]
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Sets the iterator to refer to the first code unit in its iteration range, returns that code unit, and moves the position to the second code unit.
This is an alternative to setToStart() for forward iteration with nextPostInc().
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::first32 (void) [pure virtual]
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Sets the iterator to refer to the first code point in its iteration range, and returns that code unit, This can be used to begin an iteration with next32().
Note that an iteration with next32PostInc(), beginning with, e.g., setToStart() or firstPostInc(), is more efficient.
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::first32PostInc (void) [virtual]
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Sets the iterator to refer to the first code point in its iteration range, returns that code point, and moves the position to the second code point.
This is an alternative to setToStart() for forward iteration with next32PostInc().
Reimplemented in UCharCharacterIterator.
UTextOffset CharacterIterator::setToStart () [inline]
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Sets the iterator to refer to the first code unit or code point in its iteration range.
This can be used to begin a forward iteration with nextPostInc() or next32PostInc().
Definition at line 543 of file chariter.h.
virtual UChar CharacterIterator::last (void) [pure virtual]
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Sets the iterator to refer to the last code unit in its iteration range, and returns that code unit.
This can be used to begin an iteration with previous().
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::last32 (void) [pure virtual]
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Sets the iterator to refer to the last code point in its iteration range, and returns that code unit.
This can be used to begin an iteration with previous32().
Reimplemented in UCharCharacterIterator.
UTextOffset CharacterIterator::setToEnd () [inline]
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Sets the iterator to the end of its iteration range, just behind the last code unit or code point.
This can be used to begin a backward iteration with previous() or previous32().
Definition at line 548 of file chariter.h.
virtual UChar CharacterIterator::setIndex (UTextOffset pos) [pure virtual]
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Sets the iterator to refer to the "position"-th code unit in the text-storage object the iterator refers to, and returns that code unit.
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::setIndex32 (UTextOffset pos) [pure virtual]
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Sets the iterator to refer to the beginning of the code point that contains the "position"-th code unit in the text-storage object the iterator refers to, and returns that code point.
The current position is adjusted to the beginning of the code point (its first code unit).
Reimplemented in UCharCharacterIterator.
virtual UChar CharacterIterator::current (void) const [pure virtual]
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Returns the code unit the iterator currently refers to.
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::current32 (void) const [pure virtual]
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Returns the code point the iterator currently refers to.
Reimplemented in UCharCharacterIterator.
virtual UChar CharacterIterator::next (void) [pure virtual]
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Advances to the next code unit in the iteration range (toward endIndex()), and returns that code unit.
If there are no more code units to return, returns DONE.
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::next32 (void) [pure virtual]
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Advances to the next code point in the iteration range (toward endIndex()), and returns that code point.
If there are no more code points to return, returns DONE. Note that iteration with "pre-increment" semantics is less efficient than iteration with "post-increment" semantics that is provided by next32PostInc().
Reimplemented in UCharCharacterIterator.
virtual UChar CharacterIterator::previous (void) [pure virtual]
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Advances to the previous code unit in the iteration rance (toward startIndex()), and returns that code unit.
If there are no more code units to return, returns DONE.
Reimplemented in UCharCharacterIterator.
virtual UChar32 CharacterIterator::previous32 (void) [pure virtual]
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Advances to the previous code point in the iteration rance (toward startIndex()), and returns that code point.
If there are no more code points to return, returns DONE.
Reimplemented in UCharCharacterIterator.
virtual UBool CharacterIterator::hasPrevious () [pure virtual]
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Returns FALSE if there are no more code units or code points before the current position in the iteration range.
This is used with previous() or previous32() in backward iteration.
Reimplemented in UCharCharacterIterator.
UTextOffset CharacterIterator::startIndex (void) const [inline]
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Returns the numeric index in the underlying text-storage object of the character returned by first().
Since it's possible to create an iterator that iterates across only part of a text-storage object, this number isn't necessarily 0.
Definition at line 553 of file chariter.h.
UTextOffset CharacterIterator::endIndex (void) const [inline]
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Returns the numeric index in the underlying text-storage object of the position immediately BEYOND the character returned by last().
Definition at line 558 of file chariter.h.
UTextOffset CharacterIterator::getIndex (void) const [inline]
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Returns the numeric index in the underlying text-storage object of the character the iterator currently refers to (i.e., the character returned by current()).
Definition at line 563 of file chariter.h.
int32_t CharacterIterator::getLength (void) const [inline]
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Returns the length of the entire text in the underlying text-storage object.
Definition at line 568 of file chariter.h.
virtual UTextOffset CharacterIterator::move (int32_t delta, EOrigin origin) [pure virtual]
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Moves the current position relative to the start or end of the iteration range, or relative to the current position itself.
The movement is expressed in numbers of code units forward or backward by specifying a positive or negative delta.
Reimplemented in UCharCharacterIterator.
virtual UTextOffset CharacterIterator::move32 (int32_t delta, EOrigin origin) [pure virtual]
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Moves the current position relative to the start or end of the iteration range, or relative to the current position itself.
The movement is expressed in numbers of code points forward or backward by specifying a positive or negative delta.
Reimplemented in UCharCharacterIterator.
virtual void CharacterIterator::getText (UnicodeString & result) [pure virtual]
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Copies the text under iteration into the UnicodeString referred to by "result".
result | Receives a copy of the text under iteration. |
Reimplemented in StringCharacterIterator, and UCharCharacterIterator.
CharacterIterator::CharacterIterator () [inline, protected]
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Definition at line 523 of file chariter.h.
CharacterIterator::CharacterIterator (int32_t length) [protected]
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CharacterIterator::CharacterIterator (int32_t length, UTextOffset position) [protected]
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CharacterIterator::CharacterIterator (int32_t length, UTextOffset begin, UTextOffset end, UTextOffset position) [protected]
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CharacterIterator::CharacterIterator (const CharacterIterator & that) [protected]
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CharacterIterator& CharacterIterator::operator= (const CharacterIterator & that) [protected]
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int32_t CharacterIterator::textLength [protected]
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Definition at line 531 of file chariter.h.
UTextOffset CharacterIterator::pos [protected]
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Definition at line 532 of file chariter.h.
UTextOffset CharacterIterator::begin [protected]
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Definition at line 533 of file chariter.h.
UTextOffset CharacterIterator::end [protected]
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Definition at line 534 of file chariter.h.