Initial implementation of kubevirt router along with peer router

Change-Id: Ibf97f4ca09e4cdbfea42d1edadd3e671c238878f
diff --git a/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/KubevirtRouter.java b/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/KubevirtRouter.java
new file mode 100644
index 0000000..c10116f
--- /dev/null
+++ b/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/KubevirtRouter.java
@@ -0,0 +1,128 @@
+/*
+ * Copyright 2021-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.kubevirtnetworking.api;
+
+import org.onlab.packet.IpAddress;
+
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Representation of virtual router.
+ */
+public interface KubevirtRouter {
+
+    /**
+     * Returns the router name.
+     *
+     * @return router name
+     */
+    String name();
+
+    /**
+     * Returns the router description.
+     *
+     * @return router description
+     */
+    String description();
+
+    /**
+     * Returns the SNAT enable flag.
+     *
+     * @return true if the router support SNAT, false otherwise
+     */
+    boolean enableSnat();
+
+    /**
+     * Returns a set of internal networks.
+     *
+     * @return a set of internal networks
+     */
+    Set<String> internal();
+
+    /**
+     * Returns external network along with external router IP address.
+     * We use IP address as the key, and external network name as the value.
+     *
+     * @return external network paired with external router IP address
+     */
+    Map<IpAddress, String> external();
+
+    /**
+     * Returns external peer router.
+     *
+     * @return peer router
+     */
+    KubevirtPeerRouter peerRouter();
+
+    interface Builder {
+
+        /**
+         * Builds an immutable network instance.
+         *
+         * @return kubevirt router
+         */
+        KubevirtRouter build();
+
+        /**
+         * Returns kubevirt router builder with supplied router name.
+         *
+         * @param name router name
+         * @return router builder
+         */
+        Builder name(String name);
+
+        /**
+         * Returns kubevirt router builder with supplied router description.
+         *
+         * @param description router description
+         * @return router builder
+         */
+        Builder description(String description);
+
+        /**
+         * Returns kubevirt router builder with supplied enable SNAT flag.
+         *
+         * @param flag router flag
+         * @return router builder
+         */
+        Builder enableSnat(boolean flag);
+
+        /**
+         * Returns kubevirt router builder with supplied internal networks.
+         *
+         * @param internal internal network set
+         * @return router builder
+         */
+        Builder internal(Set<String> internal);
+
+        /**
+         * Returns kubevirt router builder with supplied external network with IP.
+         *
+         * @param external external network with IP
+         * @return router builder
+         */
+        Builder external(Map<IpAddress, String> external);
+
+        /**
+         * Returns kubevirt router builder with supplied peer router.
+         *
+         * @param router peer router
+         * @return router builder
+         */
+        Builder peerRouter(KubevirtPeerRouter router);
+    }
+}