ONOS-5449 Implemented skeleton of OFAgent application

Change-Id: Ie6c719872549a004471e466a43a2b531bc48b231
diff --git a/apps/ofagent/src/main/java/org/onosproject/ofagent/api/OFSwitch.java b/apps/ofagent/src/main/java/org/onosproject/ofagent/api/OFSwitch.java
new file mode 100644
index 0000000..0252049
--- /dev/null
+++ b/apps/ofagent/src/main/java/org/onosproject/ofagent/api/OFSwitch.java
@@ -0,0 +1,47 @@
+/*
+ * 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.ofagent.api;
+
+import org.onosproject.net.Device;
+
+/**
+ * Representation of virtual OpenFlow switch.
+ */
+public interface OFSwitch extends OFSwitchService, OFControllerRoleService {
+
+    /**
+     * Returns the device information.
+     *
+     * @return virtual device
+     */
+    Device device();
+
+    /**
+     * Returns the capabilities of the switch.
+     *
+     * @return capabilities
+     */
+    OFSwitchCapabilities capabilities();
+
+    /**
+     * Returns if the switch is connected to controllers or not.
+     *
+     * @return true if the switch is connected, false otherwise
+     */
+    boolean isConnected();
+
+    // TODO add builder interface
+}