Name
CharacterIterator
Synopsis
This interface defines an API for
portably iterating through the characters that make up a string of
text, regardless of the encoding of that text. Such an API is
necessary because the number of bytes per character is different for
different encodings, and some encodings even use variable-width
characters within the same string of text. In addition to allowing
iteration, a class that implements the
CharacterIterator
interface for non-Unicode text
also performs translation of characters from their native encoding to
standard Java Unicode characters.
CharacterIterator
is similar to java.util.Enumeration
, but is
somewhat more complex than that interface. The first(
)
and last( )
methods return the first
and last characters in the text, and the next( )
and prev( )
methods allow you to loop forward or
backwards through the characters of the text. These methods return
the DONE
constant when they go beyond the first or
last character in the text; a test for this constant can be used to
terminate a loop. The CharacterIterator
interface
also allows random access to the characters in a string of text. The
getBeginIndex( )
and getEndIndex(
)
methods return the character positions for the start and
end of the string, and setIndex( )
sets the
current position. getIndex( )
returns the index of
the current position, and current( )
returns the
character at that position.
Figure 15-3. java.text.CharacterIterator
public interface CharacterIterator extends Cloneable ...
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