Favor adapter classes over service interfaces in unit tests

In unit tests that are mocking an entire interface, instead
extend the Adapter class so the unused method overrides
are no longer needed.

Change-Id: I6e332cc5cb59410f163deea223fbc94e73d83917
diff --git a/core/net/src/test/java/org/onosproject/net/device/impl/DeviceManagerTest.java b/core/net/src/test/java/org/onosproject/net/device/impl/DeviceManagerTest.java
index 0956fd6..ca8aa34 100644
--- a/core/net/src/test/java/org/onosproject/net/device/impl/DeviceManagerTest.java
+++ b/core/net/src/test/java/org/onosproject/net/device/impl/DeviceManagerTest.java
@@ -15,17 +15,20 @@
  */
 package org.onosproject.net.device.impl;
 
-import com.google.common.collect.Sets;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
 
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
-import org.onosproject.cluster.ClusterEventListener;
-import org.onosproject.cluster.ClusterService;
+import org.onlab.packet.ChassisId;
+import org.onlab.packet.IpAddress;
+import org.onosproject.cluster.ClusterServiceAdapter;
 import org.onosproject.cluster.ControllerNode;
 import org.onosproject.cluster.DefaultControllerNode;
 import org.onosproject.cluster.NodeId;
-import org.onosproject.cluster.ControllerNode.State;
 import org.onosproject.event.Event;
 import org.onosproject.event.impl.TestEventDispatcher;
 import org.onosproject.mastership.MastershipServiceAdapter;
@@ -51,18 +54,22 @@
 import org.onosproject.net.provider.AbstractProvider;
 import org.onosproject.net.provider.ProviderId;
 import org.onosproject.store.trivial.impl.SimpleDeviceStore;
-import org.onlab.packet.ChassisId;
-import org.onlab.packet.IpAddress;
 
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Set;
+import com.google.common.collect.Sets;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
 import static org.onosproject.net.Device.Type.SWITCH;
 import static org.onosproject.net.DeviceId.deviceId;
-import static org.onosproject.net.device.DeviceEvent.Type.*;
+import static org.onosproject.net.device.DeviceEvent.Type.DEVICE_ADDED;
+import static org.onosproject.net.device.DeviceEvent.Type.DEVICE_AVAILABILITY_CHANGED;
+import static org.onosproject.net.device.DeviceEvent.Type.DEVICE_UPDATED;
+import static org.onosproject.net.device.DeviceEvent.Type.PORT_ADDED;
+import static org.onosproject.net.device.DeviceEvent.Type.PORT_REMOVED;
+import static org.onosproject.net.device.DeviceEvent.Type.PORT_UPDATED;
 
 /**
  * Test codifying the device service & device provider service contracts.
@@ -310,7 +317,7 @@
     }
 
     // code clone
-    private final class TestClusterService implements ClusterService {
+    private final class TestClusterService extends ClusterServiceAdapter {
 
         ControllerNode local = new DefaultControllerNode(NID_LOCAL, LOCALHOST);
 
@@ -319,28 +326,6 @@
             return local;
         }
 
-        @Override
-        public Set<ControllerNode> getNodes() {
-            return null;
-        }
-
-        @Override
-        public ControllerNode getNode(NodeId nodeId) {
-            return null;
-        }
-
-        @Override
-        public State getState(NodeId nodeId) {
-            return null;
-        }
-
-        @Override
-        public void addListener(ClusterEventListener listener) {
-        }
-
-        @Override
-        public void removeListener(ClusterEventListener listener) {
-        }
     }
 
     private final class TestClockProviderService implements