/**
* iterator over the Tokens in the given ring, starting with the token for the node owning start
* (which does not have to be a Token in the ring)
*
* @param includeMin True if the minimum token should be returned in the ring even if it has no
* owner.
*/
public static Iterator<Token> ringIterator(
final ArrayList<Token> ring, Token start, boolean includeMin) {
if (ring.isEmpty())
return includeMin
? Iterators.singletonIterator(StorageService.getPartitioner().getMinimumToken())
: Iterators.<Token>emptyIterator();
final boolean insertMin = includeMin && !ring.get(0).isMinimum();
final int startIndex = firstTokenIndex(ring, start, insertMin);
return new AbstractIterator<Token>() {
int j = startIndex;
protected Token computeNext() {
if (j < -1) return endOfData();
try {
// return minimum for index == -1
if (j == -1) return StorageService.getPartitioner().getMinimumToken();
// return ring token for other indexes
return ring.get(j);
} finally {
j++;
if (j == ring.size()) j = insertMin ? -1 : 0;
if (j == startIndex)
// end iteration
j = -2;
}
}
};
}