package org.opendaylight.controller.cluster.sharding;
-import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import com.google.common.util.concurrent.AsyncFunction;
import com.google.common.util.concurrent.FutureCallback;
import java.util.Collection;
import java.util.List;
import java.util.Map.Entry;
+import java.util.Optional;
import java.util.stream.Collectors;
import javax.annotation.Nonnull;
import org.opendaylight.controller.cluster.databroker.actors.dds.ClientTransaction;