com.ibm.icu.text

Class CanonicalIterator


public final class CanonicalIterator
extends Object

This class allows one to iterate through all the strings that are canonically equivalent to a given string. For example, here are some sample results: Results for: {A WITH RING ABOVE}{d}{DOT ABOVE}{CEDILLA}
1: {A}{RING ABOVE}{d}{DOT ABOVE}{CEDILLA}
2: {A}{RING ABOVE}{d}{CEDILLA}{DOT ABOVE}
3: {A}{RING ABOVE}{d WITH DOT ABOVE}{CEDILLA}
4: {A}{RING ABOVE}{d WITH CEDILLA}{DOT ABOVE}
5: {A WITH RING ABOVE}{d}{DOT ABOVE}{CEDILLA}
6: {A WITH RING ABOVE}{d}{CEDILLA}{DOT ABOVE}
7: {A WITH RING ABOVE}{d WITH DOT ABOVE}{CEDILLA}
8: {A WITH RING ABOVE}{d WITH CEDILLA}{DOT ABOVE}
9: {ANGSTROM SIGN}{d}{DOT ABOVE}{CEDILLA}
10: {ANGSTROM SIGN}{d}{CEDILLA}{DOT ABOVE}
11: {ANGSTROM SIGN}{d WITH DOT ABOVE}{CEDILLA}
12: {ANGSTROM SIGN}{d WITH CEDILLA}{DOT ABOVE}

Note: the code is intended for use with small strings, and is not suitable for larger ones, since it has not been optimized for that situation.
Author:
M. Davis

Constructor Summary

CanonicalIterator(String source)
Construct a CanonicalIterator object

Method Summary

String
getSource()
Gets the NFD form of the current source we are iterating over.
String
next()
Get the next canonically equivalent string.
static void
permute(String source, boolean skipZeros, Set output)
Simple implementation of permutation.
void
reset()
Resets the iterator so that one can start again from the beginning.
void
setSource(String newSource)
Set a new source for this iterator.

Constructor Details

CanonicalIterator

public CanonicalIterator(String source)
Construct a CanonicalIterator object
Parameters:
source - string to get results for

Method Details

getSource

public String getSource()
Gets the NFD form of the current source we are iterating over.
Returns:
gets the source: NOTE: it is the NFD form of the source originally passed in

next

public String next()
Get the next canonically equivalent string.
Warning: The strings are not guaranteed to be in any particular order.
Returns:
the next string that is canonically equivalent. The value null is returned when the iteration is done.

permute

public static void permute(String source,
                           boolean skipZeros,
                           Set output)
Simple implementation of permutation.
Warning: The strings are not guaranteed to be in any particular order.
Parameters:
source - the string to find permutations for
skipZeros - set to true to skip characters with canonical combining class zero
output - the set to add the results to

reset

public void reset()
Resets the iterator so that one can start again from the beginning.

setSource

public void setSource(String newSource)
Set a new source for this iterator. Allows object reuse.
Parameters:
newSource - the source string to iterate against. This allows the same iterator to be used while changing the source string, saving object creation.

Copyright (c) 2006 IBM Corporation and others.