--- /dev/null
+/**
+ * ============LICENSE_START=======================================================
+ * org.onap.aai
+ * ================================================================================
+ * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ *
+ * ECOMP is a trademark and service mark of AT&T Intellectual Property.
+ */
+
+package org.onap.aai.validation.edges;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import org.onap.aai.edges.EdgeRuleQuery;
+import org.onap.aai.edges.enums.EdgeType;
+
+import com.jayway.jsonpath.DocumentContext;
+
+/**
+ * Validates that the given node type pair has at most one containment relationship
+ * in their edge rules.
+ *
+ */
+public class SingleContainmentValidationModule {
+
+ /**
+ * Validates that the given node type pair has at most one containment relationship
+ * in their edge rules.
+ *
+ * @param String nodeTypePair - pair of A&AI node types in the form "typeA|typeB"
+ * @param List<DocumentContext> ctxs - the ingested json to validate
+ * @return empty string if passes, else appropriate error message
+ */
+ public String validate(String nodeTypePair, List<DocumentContext> ctxs) {
+ String[] types = nodeTypePair.split("\\|");
+ EdgeRuleQuery lookup = new EdgeRuleQuery.Builder(types[0], types[1]).edgeType(EdgeType.TREE).build();
+ List<Map<String, String>> rules = new ArrayList<>();
+ for (DocumentContext ctx : ctxs) {
+ rules.addAll(ctx.read("$.rules.[?]", lookup.getFilter()));
+ }
+
+ if (rules.isEmpty() || rules.size() == 1) {
+ return "";
+ } else { //had more than one containment relationship for the pair
+ return "Pair " + nodeTypePair + " has multiple containment rules. Only one allowed.";
+ }
+ }
+}