Move ControllerToNodeId Function to api bundle

Change-Id: I80eac83cc72f9a92b594fef46d83376b42843746

-package org.onlab.onos.store.common.impl;
-
-import org.onlab.onos.cluster.ControllerNode;
-import org.onlab.onos.cluster.NodeId;
+package org.onlab.onos.cluster;
 
 import com.google.common.base.Function;
 
@@ -18,6 +15,11 @@ public final class ControllerNodeToNodeId
         return input.id();
     }
 
+    /**
+     * Returns a Function to convert ControllerNode to NodeId.
+     *
+     * @return ControllerNodeToNodeId instance.
+     */
     public static ControllerNodeToNodeId toNodeId() {
         return INSTANCE;
     }

+package org.onlab.onos.cluster;
+
+import static org.junit.Assert.*;
+import static org.onlab.onos.cluster.ControllerNodeToNodeId.toNodeId;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+import org.onlab.packet.IpPrefix;
+
+import com.google.common.collect.FluentIterable;
+
+
+public class ControllerNodeToNodeIdTest {
+
+    private static final NodeId NID1 = new NodeId("foo");
+    private static final NodeId NID2 = new NodeId("bar");
+    private static final NodeId NID3 = new NodeId("buz");
+
+    private static final IpPrefix IP1 = IpPrefix.valueOf("127.0.0.1");
+    private static final IpPrefix IP2 = IpPrefix.valueOf("127.0.0.2");
+    private static final IpPrefix IP3 = IpPrefix.valueOf("127.0.0.3");
+
+    private static final ControllerNode CN1 = new DefaultControllerNode(NID1, IP1);
+    private static final ControllerNode CN2 = new DefaultControllerNode(NID2, IP2);
+    private static final ControllerNode CN3 = new DefaultControllerNode(NID3, IP3);
+
+
+    @Test
+    public final void testToNodeId() {
+
+        final Iterable<ControllerNode> nodes = Arrays.asList(CN1, CN2, CN3);
+        final List<NodeId> nodeIds = Arrays.asList(NID1, NID2, NID3);
+
+        assertEquals(nodeIds,
+                FluentIterable.from(nodes)
+                    .transform(toNodeId())
+                    .toList());
+    }
+
+}

@@ -65,6 +65,7 @@ import java.util.concurrent.TimeUnit;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Predicates.notNull;
+import static org.onlab.onos.cluster.ControllerNodeToNodeId.toNodeId;
 import static org.onlab.onos.net.device.DeviceEvent.Type.*;
 import static org.slf4j.LoggerFactory.getLogger;
 import static org.apache.commons.lang3.concurrent.ConcurrentUtils.createIfAbsentUnchecked;
@@ -73,7 +74,6 @@ import static com.google.common.base.Verify.verify;
 import static org.onlab.util.Tools.namedThreads;
 import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
 import static org.onlab.onos.store.device.impl.GossipDeviceStoreMessageSubjects.DEVICE_ADVERTISE;
-import static org.onlab.onos.store.common.impl.ControllerNodeToNodeId.toNodeId;
 
 // TODO: give me a better name
 /**