opendaylight/md-sal/sal-dom-spi/src/main/java/org/opendaylight/controller/sal/core/spi/data/SnapshotBackedWriteTransaction.java

   1 /*
   2  * Copyright (c) 2014 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.sal.core.spi.data;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import com.google.common.annotations.Beta;
  13 import com.google.common.base.MoreObjects.ToStringHelper;
  14 import com.google.common.base.Optional;
  15 import com.google.common.base.Preconditions;
  16 import com.google.common.base.Throwables;
  17 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
  18 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  19 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  20 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  21 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  22 import org.slf4j.Logger;
  23 import org.slf4j.LoggerFactory;
  24
  25 /**
  26  * Implementation of Write transaction which is backed by
  27  * {@link DataTreeSnapshot} and executed according to
  28  * {@link org.opendaylight.controller.sal.core.spi.data.SnapshotBackedWriteTransaction.TransactionReadyPrototype}.
  29  *
  30  * @param <T> Identifier type
  31  */
  32 @Beta
  33 public class SnapshotBackedWriteTransaction<T> extends AbstractDOMStoreTransaction<T> implements DOMStoreWriteTransaction {
  34     private static final Logger LOG = LoggerFactory.getLogger(SnapshotBackedWriteTransaction.class);
  35     @SuppressWarnings("rawtypes")
  36     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction, TransactionReadyPrototype> READY_UPDATER =
  37             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class, TransactionReadyPrototype.class, "readyImpl");
  38     @SuppressWarnings("rawtypes")
  39     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction, DataTreeModification> TREE_UPDATER =
  40             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class, DataTreeModification.class, "mutableTree");
  41
  42     // non-null when not ready
  43     private volatile TransactionReadyPrototype<T> readyImpl;
  44     // non-null when not committed/closed
  45     private volatile DataTreeModification mutableTree;
  46
  47     SnapshotBackedWriteTransaction(final T identifier, final boolean debug,
  48             final DataTreeSnapshot snapshot, final TransactionReadyPrototype<T> readyImpl) {
  49         super(identifier, debug);
  50         this.readyImpl = Preconditions.checkNotNull(readyImpl, "readyImpl must not be null.");
  51         mutableTree = snapshot.newModification();
  52         LOG.debug("Write Tx: {} allocated with snapshot {}", identifier, snapshot);
  53     }
  54
  55     @Override
  56     public void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  57         checkNotReady();
  58
  59         final DataTreeModification tree = mutableTree;
  60         LOG.debug("Tx: {} Write: {}:{}", getIdentifier(), path, data);
  61
  62         try {
  63             tree.write(path, data);
  64             // FIXME: Add checked exception
  65         } catch (Exception e) {
  66             LOG.error("Tx: {}, failed to write {}:{} in {}", getIdentifier(), path, data, tree, e);
  67             // Rethrow original ones if they are subclasses of RuntimeException
  68             // or Error
  69             Throwables.propagateIfPossible(e);
  70             // FIXME: Introduce proper checked exception
  71             throw new IllegalArgumentException("Illegal input data.", e);
  72         }
  73     }
  74
  75     @Override
  76     public void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  77         checkNotReady();
  78
  79         final DataTreeModification tree = mutableTree;
  80         LOG.debug("Tx: {} Merge: {}:{}", getIdentifier(), path, data);
  81
  82         try {
  83             tree.merge(path, data);
  84             // FIXME: Add checked exception
  85         } catch (Exception e) {
  86             LOG.error("Tx: {}, failed to write {}:{} in {}", getIdentifier(), path, data, tree, e);
  87             // Rethrow original ones if they are subclasses of RuntimeException
  88             // or Error
  89             Throwables.propagateIfPossible(e);
  90             // FIXME: Introduce proper checked exception
  91             throw new IllegalArgumentException("Illegal input data.", e);
  92         }
  93     }
  94
  95     @Override
  96     public void delete(final YangInstanceIdentifier path) {
  97         checkNotReady();
  98
  99         final DataTreeModification tree = mutableTree;
 100         LOG.debug("Tx: {} Delete: {}", getIdentifier(), path);
 101
 102         try {
 103             tree.delete(path);
 104             // FIXME: Add checked exception
 105         } catch (Exception e) {
 106             LOG.error("Tx: {}, failed to delete {} in {}", getIdentifier(), path, tree, e);
 107             // Rethrow original ones if they are subclasses of RuntimeException
 108             // or Error
 109             Throwables.propagateIfPossible(e);
 110             // FIXME: Introduce proper checked exception
 111             throw new IllegalArgumentException("Illegal path to delete.", e);
 112         }
 113     }
 114
 115     /**
 116      * Exposed for {@link SnapshotBackedReadWriteTransaction}'s sake only. The contract does
 117      * not allow data access after the transaction has been closed or readied.
 118      *
 119      * @param path Path to read
 120      * @return null if the the transaction has been closed;
 121      */
 122     final Optional<NormalizedNode<?, ?>> readSnapshotNode(final YangInstanceIdentifier path) {
 123         return readyImpl == null ? null : Optional.fromJavaUtil(mutableTree.readNode(path));
 124     }
 125
 126     private final void checkNotReady() {
 127         checkState(readyImpl != null, "Transaction %s is no longer open. No further modifications allowed.",
 128                 getIdentifier());
 129     }
 130
 131     @Override
 132     public DOMStoreThreePhaseCommitCohort ready() {
 133         @SuppressWarnings("unchecked")
 134         final TransactionReadyPrototype<T> wasReady = READY_UPDATER.getAndSet(this, null);
 135         checkState(wasReady != null, "Transaction %s is no longer open", getIdentifier());
 136
 137         LOG.debug("Store transaction: {} : Ready", getIdentifier());
 138
 139         final DataTreeModification tree = mutableTree;
 140         TREE_UPDATER.lazySet(this, null);
 141         tree.ready();
 142         return wasReady.transactionReady(this, tree);
 143     }
 144
 145     @Override
 146     public void close() {
 147         @SuppressWarnings("unchecked")
 148         final TransactionReadyPrototype<T> wasReady = READY_UPDATER.getAndSet(this, null);
 149         if (wasReady != null) {
 150             LOG.debug("Store transaction: {} : Closed", getIdentifier());
 151             TREE_UPDATER.lazySet(this, null);
 152             wasReady.transactionAborted(this);
 153         } else {
 154             LOG.debug("Store transaction: {} : Closed after submit", getIdentifier());
 155         }
 156     }
 157
 158     @Override
 159     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 160         return toStringHelper.add("ready", readyImpl == null);
 161     }
 162
 163     /**
 164      * This class is intended to be implemented by Transaction factories
 165      * responsible for allocation of {@link org.opendaylight.controller.sal.core.spi.data.SnapshotBackedWriteTransaction} and
 166      * providing underlying logic for applying implementation.
 167      *
 168      * @param <T> identifier type
 169      */
 170     public abstract static class TransactionReadyPrototype<T> {
 171         /**
 172          * Called when a transaction is closed without being readied. This is not invoked for
 173          * transactions which are ready.
 174          *
 175          * @param tx Transaction which got aborted.
 176          */
 177         protected abstract void transactionAborted(final SnapshotBackedWriteTransaction<T> tx);
 178
 179         /**
 180          * Returns a commit coordinator associated with supplied transactions.
 181          *
 182          * This call must not fail.
 183          *
 184          * @param tx
 185          *            Transaction on which ready was invoked.
 186          * @param tree
 187          *            Modified data tree which has been constructed.
 188          * @return DOMStoreThreePhaseCommitCohort associated with transaction
 189          */
 190         protected abstract DOMStoreThreePhaseCommitCohort transactionReady(SnapshotBackedWriteTransaction<T> tx, DataTreeModification tree);
 191     }
 192 }