opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/EmptyTransactionCommitCohort.java

   1 /*
   2  * Copyright (c) 2016 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.cluster.databroker.actors.dds;
   9
  10 import com.google.common.util.concurrent.ListenableFuture;
  11 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  12 import org.opendaylight.mdsal.common.api.CommitInfo;
  13 import org.opendaylight.yangtools.yang.common.Empty;
  14
  15 /**
  16  * An {@link AbstractTransactionCommitCohort} for use with empty transactions. This relies on the fact that no backends
  17  * have been touched, hence all state book-keeping needs to happen only locally and shares fate with the coordinator.
  18  *
  19  * <p>
  20  * Therefore all methods can finish immediately without any effects.
  21  *
  22  * @author Robert Varga
  23  */
  24 final class EmptyTransactionCommitCohort extends AbstractTransactionCommitCohort {
  25     EmptyTransactionCommitCohort(final AbstractClientHistory parent, final TransactionIdentifier txId) {
  26         super(parent, txId);
  27     }
  28
  29     @Override
  30     public ListenableFuture<Boolean> canCommit() {
  31         return TRUE_FUTURE;
  32     }
  33
  34     @Override
  35     public ListenableFuture<Empty> preCommit() {
  36         return EMPTY_FUTURE;
  37     }
  38
  39     @Override
  40     public ListenableFuture<Empty> abort() {
  41         complete();
  42         return EMPTY_FUTURE;
  43     }
  44
  45     @Override
  46     public ListenableFuture<CommitInfo> commit() {
  47         complete();
  48         return CommitInfo.emptyFluentFuture();
  49     }
  50 }