+import com.google.common.util.concurrent.ListenableFuture;
+import java.util.List;
+import java.util.Optional;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import org.opendaylight.openflowplugin.api.openflow.registry.CommonDeviceRegistry;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.FlowCapableNode;