final int index = indexOf(B, r) + 1;
if (null == data[index]) {
if (null != base && index < base.length && null != base[index]) {
data[index] = new SparseConceptSet();
data[index].addAll(base[index]);
return new ReadonlyConceptSet(data[index]);
} else {
return IConceptSet.EMPTY_SET;
}
} else {
return new ReadonlyConceptSet(data[index]);
}
}