Add resource API to query registered resource

Change-Id: Ibf53a0fa383043d17e78578093eb3055631796d0
diff --git a/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java b/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java
index 3076ec9..974fe5e 100644
--- a/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java
+++ b/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java
@@ -162,6 +162,15 @@
     Collection<Resource> getAvailableResources(Resource parent);
 
     /**
+     * Returns resources registered under the specified resource.
+     *
+     * @param parent parent resource
+     * @return registered resources under the specified resource
+     */
+    Collection<Resource> getRegisteredResources(Resource parent);
+
+
+    /**
      * Returns the availability of the specified resource.
      *
      * @param resource resource to check the availability