private ITupleIterator computeSimpleCartesianProduct(
ITupleIterator leftTuples, ITupleIterator rightTuples) {
List<Tuple> result = new ArrayList<Tuple>();
while (leftTuples.hasNext()) {
Tuple leftTuple = leftTuples.next();
if (logger.isDebugEnabled()) logger.debug("Left tuple in cartesian product: " + leftTuple);
while (rightTuples.hasNext()) {
Tuple rightTuple = rightTuples.next();
if (logger.isDebugEnabled())
logger.debug("Right tuple in cartesian product: " + rightTuple);
Tuple joinedTuple = joinTuples(leftTuple, rightTuple);
result.add(joinedTuple);
}
rightTuples.reset();
}
leftTuples.reset();
return new ListTupleIterator(result);
}
