/**
* Canonicalize an ordered set of exceptions. In the canonical form, none of the RVVExceptions
* have any received versions.
*
* @param exceptions
* @return The canonicalized set of exceptions.
*/
protected List<RVVException> canonicalExceptions(List<RVVException> exceptions) {
LinkedList<RVVException> canon = new LinkedList<RVVException>();
if (exceptions != null) {
// Iterate through the set of exceptions
for (RVVException exception : exceptions) {
if (exception.isEmpty()) {
canon.add(exception);
} else {
long previous = exception.previousVersion;
// Iterate through the set of received versions for this exception
int insertAt = canon.size();
for (ReceivedVersionsIterator it = exception.receivedVersionsIterator(); it.hasNext(); ) {
Long received = it.next();
// If we find a gap between the previous received version and the
// next received version, add an exception.
if (received != previous + 1) {
canon.add(insertAt, RVVException.createException(previous, received));
}
// move the previous reference
previous = received;
}
// if there is a gap between the last received version and the next
// version, add an exception
// this also handles the case where the RVV has no received versions,
// because previous==exception.previousVersion in that case.
if (exception.nextVersion != previous + 1) {
canon.add(insertAt, RVVException.createException(previous, exception.nextVersion));
}
}
}
}
return canon;
}
