Prohibit null in instantiation

Change-Id: If5229337d1531eae25cbd2b31ca8e6a117d022f3
diff --git a/core/api/src/main/java/org/onosproject/net/intent/IntentOperations.java b/core/api/src/main/java/org/onosproject/net/intent/IntentOperations.java
index b668fcf..a9b3d44 100644
--- a/core/api/src/main/java/org/onosproject/net/intent/IntentOperations.java
+++ b/core/api/src/main/java/org/onosproject/net/intent/IntentOperations.java
@@ -42,6 +42,9 @@
      * @param operations list of intent operations
      */
     private IntentOperations(List<IntentOperation> operations, ApplicationId appId) {
+        checkNotNull(operations);
+        checkNotNull(appId);
+
         this.operations = operations;
         this.appId = appId;
     }