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);
}
private EquivalenceClassForSymmetricEGD readNextEquivalenceClass(
ITupleIterator it,
Dependency egd,
IDatabase deltaDB,
String stepId,
IChaseState chaseState,
Scenario scenario) {
if (!it.hasNext() && (this.lastTupleHandled || this.lastTuple == null)) {
return null;
}
EquivalenceClassForSymmetricEGD equivalenceClass = createEquivalenceClass(egd);
if (lastTuple != null && !this.lastTupleHandled) {
if (logger.isDebugEnabled())
logger.debug("Reading tuple : " + this.lastTuple.toStringWithOIDAndAlias());
addTuple(
this.lastTuple,
equivalenceClass,
scenario.getCostManagerConfiguration(),
deltaDB,
stepId,
scenario);
this.lastTupleHandled = true;
}
if (logger.isDebugEnabled()) logger.debug("Reading next equivalence class...");
while (it.hasNext()) {
if (chaseState.isCancelled())
ChaseUtility.stopChase(
chaseState); // throw new ChaseException("Chase interrupted by user");
Tuple tuple = it.next();
if (logger.isDebugEnabled())
logger.debug("Reading tuple : " + tuple.toStringWithOIDAndAlias());
if (lastTuple == null
|| equivalenceClass.isEmpty()
|| EquivalenceClassUtility.sameEquivalenceClass(tuple, this.lastTuple, egd)) {
addTuple(
tuple,
equivalenceClass,
scenario.getCostManagerConfiguration(),
deltaDB,
stepId,
scenario);
this.lastTuple = tuple;
this.lastTupleHandled = true;
} else {
if (logger.isDebugEnabled()) logger.debug("Equivalence class is finished...");
if (equivalenceClass.isEmpty()) {
throw new IllegalArgumentException(
"Unable to create equivalence class for egd:\n"
+ egd
+ "\nLast tuple: \n"
+ lastTuple
+ "\nCurrent tuple: \n"
+ tuple);
}
this.lastTuple = tuple;
this.lastTupleHandled = false;
break;
}
}
if (logger.isDebugEnabled()) logger.debug("Equivalence class loaded");
if (logger.isDebugEnabled())
logger.debug("-------- Equivalence class:\n" + equivalenceClass + "\n---------------");
return equivalenceClass;
}
private boolean noMoreTuples(ITupleIterator it) {
return (!it.hasNext() && lastTupleHandled);
}