Add a set of interfaces for k8s pod, service, endpoint

Change-Id: Ie67c5d1a0678bdd651dac24363ab3feab5098919
diff --git a/apps/k8s-networking/api/src/main/java/org/onosproject/k8snetworking/api/K8sServiceAdminService.java b/apps/k8s-networking/api/src/main/java/org/onosproject/k8snetworking/api/K8sServiceAdminService.java
new file mode 100644
index 0000000..097b1ce
--- /dev/null
+++ b/apps/k8s-networking/api/src/main/java/org/onosproject/k8snetworking/api/K8sServiceAdminService.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2019-present Open Networking Foundation
+ *
+ * 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.
+ */
+package org.onosproject.k8snetworking.api;
+
+import io.fabric8.kubernetes.api.model.Service;
+
+/**
+ * Service for administering the inventory of kubernetes service.
+ */
+public interface K8sServiceAdminService extends K8sServiceService {
+
+    /**
+     * Creates a kubernetes service with the given information.
+     *
+     * @param service the new kubernetes service
+     */
+    void createService(Service service);
+
+    /**
+     * Updates the kubernetes service with the given information.
+     *
+     * @param service the updated kubernetes service
+     */
+    void updateService(Service service);
+
+    /**
+     * Removes the kubernetes service.
+     *
+     * @param uid kubernetes service UID
+     */
+    void removeService(String uid);
+
+    /**
+     * Clears the existing services.
+     */
+    void clear();
+}