[ONOS-6395] (vNet) Defining mastership service

Defines the interface for mastership service for virtual networks.
This service is needed to achieve HA and load balancing.

Change-Id: I5b68511c114ebd818429f4f6eb622dff95dd8630
diff --git a/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/SimpleVirtualMastershipStore.java b/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/SimpleVirtualMastershipStore.java
new file mode 100644
index 0000000..bd972b2
--- /dev/null
+++ b/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/SimpleVirtualMastershipStore.java
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * 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.incubator.store.virtual.impl;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Service;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.cluster.RoleInfo;
+import org.onosproject.incubator.net.virtual.NetworkId;
+import org.onosproject.incubator.net.virtual.VirtualNetworkMastershipStore;
+import org.onosproject.mastership.MastershipEvent;
+import org.onosproject.mastership.MastershipStoreDelegate;
+import org.onosproject.mastership.MastershipTerm;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.MastershipRole;
+import org.slf4j.Logger;
+
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Implementation of the virtual network mastership store to manage inventory of
+ * mastership using trivial in-memory implementation.
+ */
+@Component(immediate = true)
+@Service
+public class SimpleVirtualMastershipStore
+        extends AbstractVirtualStore<MastershipEvent, MastershipStoreDelegate>
+        implements VirtualNetworkMastershipStore {
+
+    private final Logger log = getLogger(getClass());
+
+    @Activate
+    public void activate() {
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        log.info("Stopped");
+    }
+
+    @Override
+    public CompletableFuture<MastershipRole> requestRole(NetworkId networkId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public MastershipRole getRole(NetworkId networkId, NodeId nodeId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public NodeId getMaster(NetworkId networkId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public RoleInfo getNodes(NetworkId networkId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public Set<DeviceId> getDevices(NetworkId networkId, NodeId nodeId) {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<MastershipEvent> setMaster(NetworkId networkId,
+                                                        NodeId nodeId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public MastershipTerm getTermFor(NetworkId networkId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<MastershipEvent> setStandby(NetworkId networkId,
+                                                         NodeId nodeId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public CompletableFuture<MastershipEvent> relinquishRole(NetworkId networkId,
+                                                             NodeId nodeId, DeviceId deviceId) {
+        return null;
+    }
+
+    @Override
+    public void relinquishAllRole(NetworkId networkId, NodeId nodeId) {
+
+    }
+}