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