opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/LocalTransactionContext.java

   1 /*
   2  * Copyright (c) 2015 Brocade Communications 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.datastore;
   9
  10 import akka.actor.ActorSelection;
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.util.concurrent.FutureCallback;
  13 import com.google.common.util.concurrent.Futures;
  14 import com.google.common.util.concurrent.MoreExecutors;
  15 import com.google.common.util.concurrent.SettableFuture;
  16 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  17 import org.opendaylight.controller.cluster.datastore.messages.AbstractRead;
  18 import org.opendaylight.controller.cluster.datastore.modification.AbstractModification;
  19 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  20 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransaction;
  21 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  22 import scala.concurrent.Future;
  23
  24 /**
  25  * Processes front-end transaction operations locally before being committed to the destination shard.
  26  * Instances of this class are used when the destination shard is local to the caller.
  27  *
  28  * @author Thomas Pantelis
  29  */
  30 abstract class LocalTransactionContext extends AbstractTransactionContext {
  31     private final DOMStoreTransaction txDelegate;
  32     private final LocalTransactionReadySupport readySupport;
  33     private Exception operationError;
  34
  35     LocalTransactionContext(final DOMStoreTransaction txDelegate, final TransactionIdentifier identifier,
  36             final LocalTransactionReadySupport readySupport) {
  37         super(identifier);
  38         this.txDelegate = Preconditions.checkNotNull(txDelegate);
  39         this.readySupport = readySupport;
  40     }
  41
  42     protected abstract DOMStoreWriteTransaction getWriteDelegate();
  43
  44     protected abstract DOMStoreReadTransaction getReadDelegate();
  45
  46     @Override
  47     @SuppressWarnings("checkstyle:IllegalCatch")
  48     public void executeModification(final AbstractModification modification) {
  49         incrementModificationCount();
  50         if (operationError == null) {
  51             try {
  52                 modification.apply(getWriteDelegate());
  53             } catch (Exception e) {
  54                 operationError = e;
  55             }
  56         }
  57     }
  58
  59     @Override
  60     public <T> void executeRead(final AbstractRead<T> readCmd, final SettableFuture<T> proxyFuture) {
  61         Futures.addCallback(readCmd.apply(getReadDelegate()), new FutureCallback<T>() {
  62             @Override
  63             public void onSuccess(final T result) {
  64                 proxyFuture.set(result);
  65             }
  66
  67             @Override
  68             public void onFailure(final Throwable failure) {
  69                 proxyFuture.setException(failure);
  70             }
  71         }, MoreExecutors.directExecutor());
  72     }
  73
  74     private LocalThreePhaseCommitCohort ready() {
  75         logModificationCount();
  76         return readySupport.onTransactionReady(getWriteDelegate(), operationError);
  77     }
  78
  79     @Override
  80     public Future<ActorSelection> readyTransaction() {
  81         final LocalThreePhaseCommitCohort cohort = ready();
  82         return cohort.initiateCoordinatedCommit();
  83     }
  84
  85     @Override
  86     public Future<Object> directCommit() {
  87         final LocalThreePhaseCommitCohort cohort = ready();
  88         return cohort.initiateDirectCommit();
  89     }
  90
  91     @Override
  92     public void closeTransaction() {
  93         txDelegate.close();
  94     }
  95 }