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
diff --git a/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceManager.java b/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceManager.java
index 83ae6e0..ae7c7f4 100644
--- a/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceManager.java
+++ b/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceManager.java
@@ -158,6 +158,13 @@
     }
 
     @Override
+    public Collection<Resource> getRegisteredResources(Resource parent) {
+        checkNotNull(parent);
+
+        return store.getChildResources(parent);
+    }
+
+    @Override
     public boolean isAvailable(Resource resource) {
         checkNotNull(resource);
 
diff --git a/core/net/src/test/java/org/onosproject/net/intent/impl/compiler/MockResourceService.java b/core/net/src/test/java/org/onosproject/net/intent/impl/compiler/MockResourceService.java
index 16c3c9b..a41616b 100644
--- a/core/net/src/test/java/org/onosproject/net/intent/impl/compiler/MockResourceService.java
+++ b/core/net/src/test/java/org/onosproject/net/intent/impl/compiler/MockResourceService.java
@@ -101,6 +101,11 @@
     }
 
     @Override
+    public Collection<Resource> getRegisteredResources(Resource parent) {
+        return getAvailableResources(parent);
+    }
+
+    @Override
     public boolean isAvailable(Resource resource) {
         return true;
     }