+ /**
+ * Extract the multiplicity type from the Edge rules
+ *
+ * @param key
+ * @return
+ * @throws CrudException
+ */
+ public String lookupRelationMultiplicity(String key) throws CrudException {
+ EdgeRule edgeRule = relationshipRules.get(key);
+
+ if (edgeRule == null) {
+ throw new CrudException("Invalid source/target/relationship type: " + key, Status.BAD_REQUEST);
+ }
+
+ if (edgeRule.getMultiplicityRule() != null) {
+ return edgeRule.getMultiplicityRule().toString();
+ }
+
+ return null;
+ }
+