java.text.CharacterIterator
public interface java.text.CharacterIterator extends java.lang.Cloneable
subinterfaces: java.text.AttributedCharacterIterator
implementing classes: java.text.StringCharacterIterator
since:??
see also: [java.text.StringCharacterIterator, java.text.AttributedCharacterIterator
fields: java.text.CharacterIterator.DONE
methods: clone(), current(), first(), getBeginIndex(), getEndIndex(), getIndex(), last(), next(), previous(), setIndex(int position)
This interface defines a protocol for bidirectional iteration over text. The iterator iterates over a bounded sequence of characters.
Characters are indexed with values beginning with the value returned by getBeginIndex() and continuing through the value returned
by getEndIndex()-1.
Iterators maintain a current character index, whose valid range is from getBeginIndex() to getEndIndex(); the value getEndIndex()
is included to allow handling of zero-length text ranges and for historical reasons. The current index can be retrieved by calling
getIndex() and set directly by calling setIndex(), first(), and last().
The methods previous() and next() are used for iteration. They return DONE if they would move outside the range from
getBeginIndex() to getEndIndex() -1, signaling that the iterator has reached the end of the sequence. DONE is also returned by
other methods to indicate that the current index is outside this range.
Examples:
Traverse the text from start to finish
public void traverseForward(CharacterIterator iter) {
for(char c = iter.first(); c != CharacterIterator.DONE; c = iter.next()) {
processChar(c);
}
}
Traverse the text backwards, from end to start
public void traverseBackward(CharacterIterator iter) {
for(char c = iter.last(); c != CharacterIterator.DONE; c = iter.previous()) {
processChar(c);
}
}
Traverse both forward and backward from a given position in the text. Calls to notBoundary() in this example represents some
additional stopping criteria.
public void traverseOut(CharacterIterator iter, int pos) {
for (char c = iter.setIndex(pos);
c != CharacterIterator.DONE && notBoundary(c);
c = iter.next()) {
}
int end = iter.getIndex();
for (char c = iter.setIndex(pos);
c != CharacterIterator.DONE && notBoundary(c);
c = iter.previous()) {
}
int start = iter.getIndex();
processSection(start, end);
}
source: Sun's Java documentation for JDK 1.3
Sun Microsystems: www.sun.com | Sun's Java: java.sun.com | JDK 1.3 API docs: http://java.sun.com/j2se/1.3/docs/api/index.html