Fix Mcast store and Mcast CLI

Change-Id: I8f2bfe37738d7a7ee19ebcd79e13baa4abb01a76
diff --git a/apps/mcast/cli/src/main/java/org/onosproject/mcast/cli/McastGroupCompleter.java b/apps/mcast/cli/src/main/java/org/onosproject/mcast/cli/McastGroupCompleter.java
new file mode 100644
index 0000000..9c4bddd
--- /dev/null
+++ b/apps/mcast/cli/src/main/java/org/onosproject/mcast/cli/McastGroupCompleter.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2018-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.mcast.cli;
+
+import org.onlab.packet.IpAddress;
+import org.onlab.util.Tools;
+import org.onosproject.cli.AbstractChoicesCompleter;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.mcast.api.McastRoute;
+import org.onosproject.mcast.api.MulticastRouteService;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * Mcast group Completer.
+ */
+public class McastGroupCompleter extends AbstractChoicesCompleter {
+
+    @Override
+    protected List<String> choices() {
+        MulticastRouteService service = AbstractShellCommand.get(MulticastRouteService.class);
+
+        return Tools.stream(service.getRoutes())
+                .map(McastRoute::group)
+                .map(IpAddress::toString)
+                .collect(Collectors.toList());
+    }
+
+}