throw new InvalidArgument(
"null parameter(s) provided to resolve API.");
}
// resolve subject bel term to kam node.
final KamNode subjectKamNode = resolve(kam, kAMStore, subject, nsmap, eq);
if (subjectKamNode == null) return null;
// resolve object bel term to kam node.
final KamNode objectKamNode = resolve(kam, kAMStore, object, nsmap, eq);
if (objectKamNode == null) return null;
// only resolve edge if kam nodes resolved
return resolveEdge(kam, subjectKamNode, r, objectKamNode);
}