[ONOS-3585] Add the cli of setting external port name.

Change-Id: I71833063c8e3f27fff7d69499cd3d24fd5537274
diff --git a/apps/vtn/vtnmgr/src/main/java/org/onosproject/vtn/cli/VtnCommand.java b/apps/vtn/vtnmgr/src/main/java/org/onosproject/vtn/cli/VtnCommand.java
new file mode 100644
index 0000000..92900f2
--- /dev/null
+++ b/apps/vtn/vtnmgr/src/main/java/org/onosproject/vtn/cli/VtnCommand.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2015 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.vtn.cli;
+
+import org.apache.karaf.shell.commands.Command;
+import org.apache.karaf.shell.commands.Option;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.vtn.manager.impl.VTNManager;
+
+/**
+ * Supports for updating the external gateway virtualPort.
+ */
+@Command(scope = "onos", name = "externalportname-set",
+        description = "Supports for setting the external port name.")
+public class VtnCommand extends AbstractShellCommand {
+
+    @Option(name = "-n", aliases = "--name", description = "external port name.", required = true,
+            multiValued = false)
+    String exPortName = "";
+
+    @Override
+    protected void execute() {
+        VTNManager.setExPortName(exPortName);
+    }
+}