com.ibm.icu.text
Class UnicodeSetIterator

java.lang.Object
  extended by com.ibm.icu.text.UnicodeSetIterator

public class UnicodeSetIterator
extends Object

UnicodeSetIterator iterates over the contents of a UnicodeSet. It iterates over either code points or code point ranges. After all code points or ranges have been returned, it returns the multicharacter strings of the UnicodSet, if any.

To iterate over code points, use a loop like this:

 UnicodeSetIterator it = new UnicodeSetIterator(set);
 while (set.next()) {
   if (set.codepoint != UnicodeSetIterator.IS_STRING) {
     processCodepoint(set.codepoint);
   } else {
     processString(set.string);
   }
 }
 

To iterate over code point ranges, use a loop like this:

 UnicodeSetIterator it = new UnicodeSetIterator(set);
 while (set.nextRange()) {
   if (set.codepoint != UnicodeSetIterator.IS_STRING) {
     processCodepointRange(set.codepoint, set.codepointEnd);
   } else {
     processString(set.string);
   }
 }
 

Author:
M. Davis

Field Summary
 int codepoint
          Current code point, or the special value IS_STRING, if the iterator points to a string.
 int codepointEnd
          When iterating over ranges using nextRange(), codepointEnd contains the inclusive end of the iteration range, if codepoint !
protected  int endElement
           
static int IS_STRING
          Value of codepoint if the iterator points to a string.
protected  int nextElement
           
 String string
          If codepoint == IS_STRING, then string points to the current string.
 
Constructor Summary
UnicodeSetIterator()
          Create an iterator over nothing.
UnicodeSetIterator(UnicodeSet set)
          Create an iterator over the given set.
 
Method Summary
 String getString()
          Gets the current string from the iterator.
protected  void loadRange(int range)
           
 boolean next()
          Returns the next element in the set, either a single code point or a string.
 boolean nextRange()
          Returns the next element in the set, either a code point range or a string.
 void reset()
          Resets this iterator to the start of the set.
 void reset(UnicodeSet set)
          Sets this iterator to visit the elements of the given set and resets it to the start of that set.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

IS_STRING

public static int IS_STRING
Value of codepoint if the iterator points to a string. If codepoint == IS_STRING, then examine string for the current iteration result.


codepoint

public int codepoint
Current code point, or the special value IS_STRING, if the iterator points to a string.


codepointEnd

public int codepointEnd
When iterating over ranges using nextRange(), codepointEnd contains the inclusive end of the iteration range, if codepoint != IS_STRING. If iterating over code points using next(), or if codepoint == IS_STRING, then the value of codepointEnd is undefined.


string

public String string
If codepoint == IS_STRING, then string points to the current string. If codepoint != IS_STRING, the value of string is undefined.


endElement

protected int endElement

nextElement

protected int nextElement
Constructor Detail

UnicodeSetIterator

public UnicodeSetIterator(UnicodeSet set)
Create an iterator over the given set.

Parameters:
set - set to iterate over

UnicodeSetIterator

public UnicodeSetIterator()
Create an iterator over nothing. next() and nextRange() return false. This is a convenience constructor allowing the target to be set later.

Method Detail

next

public boolean next()
Returns the next element in the set, either a single code point or a string. If there are no more elements in the set, return false. If codepoint == IS_STRING, the value is a string in the string field. Otherwise the value is a single code point in the codepoint field.

The order of iteration is all code points in sorted order, followed by all strings sorted order. codepointEnd is undefined after calling this method. string is undefined unless codepoint == IS_STRING. Do not mix calls to next() and nextRange() without calling reset() between them. The results of doing so are undefined.

Returns:
true if there was another element in the set and this object contains the element.

nextRange

public boolean nextRange()
Returns the next element in the set, either a code point range or a string. If there are no more elements in the set, return false. If codepoint == IS_STRING, the value is a string in the string field. Otherwise the value is a range of one or more code points from codepoint to codepointeEnd inclusive.

The order of iteration is all code points ranges in sorted order, followed by all strings sorted order. Ranges are disjoint and non-contiguous. string is undefined unless codepoint == IS_STRING. Do not mix calls to next() and nextRange() without calling reset() between them. The results of doing so are undefined.

Returns:
true if there was another element in the set and this object contains the element.

reset

public void reset(UnicodeSet set)
Sets this iterator to visit the elements of the given set and resets it to the start of that set. The iterator is valid only so long as set is valid.

Parameters:
set - the set to iterate over.

reset

public void reset()
Resets this iterator to the start of the set.


getString

public String getString()
Gets the current string from the iterator. Only use after calling next(), not nextRange().


loadRange

protected void loadRange(int range)


Copyright (c) 2006 IBM Corporation and others.