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

   1 /*
   2  * Copyright (c) 2015 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.datastore;
   9
  10 import com.google.common.base.MoreObjects;
  11 import com.google.common.base.Preconditions;
  12 import javax.annotation.concurrent.NotThreadSafe;
  13 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
  14 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  15 import org.opendaylight.yangtools.concepts.Identifiable;
  16 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  17 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  18 import org.slf4j.Logger;
  19 import org.slf4j.LoggerFactory;
  20
  21 /**
  22  * A transaction chain attached to a Shard.
  23  */
  24 @NotThreadSafe
  25 final class ShardDataTreeTransactionChain extends ShardDataTreeTransactionParent
  26         implements Identifiable<LocalHistoryIdentifier> {
  27
  28     private static final Logger LOG = LoggerFactory.getLogger(ShardDataTreeTransactionChain.class);
  29     private final LocalHistoryIdentifier chainId;
  30     private final ShardDataTree dataTree;
  31
  32     private ReadWriteShardDataTreeTransaction previousTx;
  33     private ReadWriteShardDataTreeTransaction openTransaction;
  34     private boolean closed;
  35
  36     ShardDataTreeTransactionChain(final LocalHistoryIdentifier localHistoryIdentifier, final ShardDataTree dataTree) {
  37         this.chainId = Preconditions.checkNotNull(localHistoryIdentifier);
  38         this.dataTree = Preconditions.checkNotNull(dataTree);
  39     }
  40
  41     private DataTreeSnapshot getSnapshot() {
  42         Preconditions.checkState(!closed, "TransactionChain %s has been closed", this);
  43         Preconditions.checkState(openTransaction == null, "Transaction %s is open", openTransaction);
  44
  45         if (previousTx == null) {
  46             LOG.debug("Opening an unchained snapshot in {}", chainId);
  47             return dataTree.takeSnapshot();
  48         }
  49
  50         LOG.debug("Reusing a chained snapshot in {}", chainId);
  51         return previousTx.getSnapshot();
  52     }
  53
  54     ReadOnlyShardDataTreeTransaction newReadOnlyTransaction(final TransactionIdentifier txId) {
  55         final DataTreeSnapshot snapshot = getSnapshot();
  56         LOG.debug("Allocated read-only transaction {} snapshot {}", txId, snapshot);
  57
  58         return new ReadOnlyShardDataTreeTransaction(this, txId, snapshot);
  59     }
  60
  61     ReadWriteShardDataTreeTransaction newReadWriteTransaction(final TransactionIdentifier txId) {
  62         final DataTreeSnapshot snapshot = getSnapshot();
  63         LOG.debug("Allocated read-write transaction {} snapshot {}", txId, snapshot);
  64
  65         openTransaction = new ReadWriteShardDataTreeTransaction(this, txId, snapshot.newModification());
  66         return openTransaction;
  67     }
  68
  69     void close() {
  70         closed = true;
  71         LOG.debug("Closing chain {}", chainId);
  72     }
  73
  74     @Override
  75     void abortFromTransactionActor(final AbstractShardDataTreeTransaction<?> transaction) {
  76         if (transaction instanceof ReadWriteShardDataTreeTransaction) {
  77             Preconditions.checkState(openTransaction != null,
  78                     "Attempted to abort transaction %s while none is outstanding", transaction);
  79             LOG.debug("Aborted open transaction {}", transaction);
  80             openTransaction = null;
  81         }
  82     }
  83
  84     @Override
  85     void abortTransaction(final AbstractShardDataTreeTransaction<?> transaction, final Runnable callback) {
  86         abortFromTransactionActor(transaction);
  87         dataTree.abortTransaction(transaction, callback);
  88     }
  89
  90     @Override
  91     ShardDataTreeCohort finishTransaction(final ReadWriteShardDataTreeTransaction transaction) {
  92         Preconditions.checkState(openTransaction != null,
  93                 "Attempted to finish transaction %s while none is outstanding", transaction);
  94
  95         // dataTree is finalizing ready the transaction, we just record it for the next
  96         // transaction in chain
  97         final ShardDataTreeCohort delegate = dataTree.finishTransaction(transaction);
  98         openTransaction = null;
  99         previousTx = transaction;
 100         LOG.debug("Committing transaction {}", transaction);
 101
 102         return new ChainedCommitCohort(this, transaction, delegate);
 103     }
 104
 105     @Override
 106     public String toString() {
 107         return MoreObjects.toStringHelper(this).add("id", chainId).toString();
 108     }
 109
 110     void clearTransaction(final ReadWriteShardDataTreeTransaction transaction) {
 111         if (transaction.equals(previousTx)) {
 112             previousTx = null;
 113         }
 114     }
 115
 116     @Override
 117     public LocalHistoryIdentifier getIdentifier() {
 118         return chainId;
 119     }
 120
 121     @Override
 122     ShardDataTreeCohort createFailedCohort(final TransactionIdentifier txId, final DataTreeModification mod,
 123             final Exception failure) {
 124         return dataTree.createFailedCohort(txId, mod, failure);
 125     }
 126
 127     @Override
 128     ShardDataTreeCohort createReadyCohort(final TransactionIdentifier txId, final DataTreeModification mod) {
 129         return dataTree.createReadyCohort(txId, mod);
 130     }
 131 }