-import com.google.common.util.concurrent.Futures;
-import com.google.common.util.concurrent.ListenableFuture;
-import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateTip;
-import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
+import java.util.Optional;
+import java.util.SortedSet;
+import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
+import org.opendaylight.yangtools.yang.common.Empty;
+import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidate;
+import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidateTip;
+import org.opendaylight.yangtools.yang.data.tree.api.DataTreeModification;