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 javax.annotation.Nullable;
  19 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  20 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  21 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  22 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25
  26 /**
  27  * Implementation of Write transaction which is backed by
  28  * {@link DataTreeSnapshot} and executed according to
  29  * {@link org.opendaylight.controller.sal.core.spi.data.SnapshotBackedWriteTransaction.TransactionReadyPrototype}.
  30  *
  31  * @param <T> Identifier type
  32  */
  33 @Beta
  34 public class SnapshotBackedWriteTransaction<T> extends AbstractDOMStoreTransaction<T> implements DOMStoreWriteTransaction {
  35     private static final Logger LOG = LoggerFactory.getLogger(SnapshotBackedWriteTransaction.class);
  36     @SuppressWarnings("rawtypes")
  37     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction, TransactionReadyPrototype> READY_UPDATER =
  38             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class, TransactionReadyPrototype.class, "readyImpl");
  39     @SuppressWarnings("rawtypes")
  40     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction, DataTreeModification> TREE_UPDATER =
  41             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class, DataTreeModification.class, "mutableTree");
  42
  43     // non-null when not ready
  44     private volatile TransactionReadyPrototype<T> readyImpl;
  45     // non-null when not committed/closed
  46     private volatile DataTreeModification mutableTree;
  47
  48     SnapshotBackedWriteTransaction(final T identifier, final boolean debug,
  49             final DataTreeSnapshot snapshot, final TransactionReadyPrototype<T> readyImpl) {
  50         super(identifier, debug);
  51         this.readyImpl = Preconditions.checkNotNull(readyImpl, "readyImpl must not be null.");
  52         mutableTree = snapshot.newModification();
  53         LOG.debug("Write Tx: {} allocated with snapshot {}", identifier, snapshot);
  54     }
  55
  56     @Override
  57     public void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  58         checkNotReady();
  59
  60         final DataTreeModification tree = mutableTree;
  61         LOG.debug("Tx: {} Write: {}:{}", getIdentifier(), path, data);
  62
  63         try {
  64             tree.write(path, data);
  65             // FIXME: Add checked exception
  66         } catch (Exception e) {
  67             LOG.error("Tx: {}, failed to write {}:{} in {}", getIdentifier(), path, data, tree, e);
  68             // Rethrow original ones if they are subclasses of RuntimeException
  69             // or Error
  70             Throwables.propagateIfPossible(e);
  71             // FIXME: Introduce proper checked exception
  72             throw new IllegalArgumentException("Illegal input data.", e);
  73         }
  74     }
  75
  76     @Override
  77     public void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  78         checkNotReady();
  79
  80         final DataTreeModification tree = mutableTree;
  81         LOG.debug("Tx: {} Merge: {}:{}", getIdentifier(), path, data);
  82
  83         try {
  84             tree.merge(path, data);
  85             // FIXME: Add checked exception
  86         } catch (Exception e) {
  87             LOG.error("Tx: {}, failed to write {}:{} in {}", getIdentifier(), path, data, tree, e);
  88             // Rethrow original ones if they are subclasses of RuntimeException
  89             // or Error
  90             Throwables.propagateIfPossible(e);
  91             // FIXME: Introduce proper checked exception
  92             throw new IllegalArgumentException("Illegal input data.", e);
  93         }
  94     }
  95
  96     @Override
  97     public void delete(final YangInstanceIdentifier path) {
  98         checkNotReady();
  99
 100         final DataTreeModification tree = mutableTree;
 101         LOG.debug("Tx: {} Delete: {}", getIdentifier(), path);
 102
 103         try {
 104             tree.delete(path);
 105             // FIXME: Add checked exception
 106         } catch (Exception e) {
 107             LOG.error("Tx: {}, failed to delete {} in {}", getIdentifier(), path, tree, e);
 108             // Rethrow original ones if they are subclasses of RuntimeException
 109             // or Error
 110             Throwables.propagateIfPossible(e);
 111             // FIXME: Introduce proper checked exception
 112             throw new IllegalArgumentException("Illegal path to delete.", e);
 113         }
 114     }
 115
 116     /**
 117      * Exposed for {@link SnapshotBackedReadWriteTransaction}'s sake only. The contract does
 118      * not allow data access after the transaction has been closed or readied.
 119      *
 120      * @param path Path to read
 121      * @return null if the the transaction has been closed;
 122      */
 123     final Optional<NormalizedNode<?, ?>> readSnapshotNode(final YangInstanceIdentifier path) {
 124         return readyImpl == null ? null : Optional.fromJavaUtil(mutableTree.readNode(path));
 125     }
 126
 127     private final void checkNotReady() {
 128         checkState(readyImpl != null, "Transaction %s is no longer open. No further modifications allowed.",
 129                 getIdentifier());
 130     }
 131
 132     @Override
 133     public DOMStoreThreePhaseCommitCohort ready() {
 134         @SuppressWarnings("unchecked")
 135         final TransactionReadyPrototype<T> wasReady = READY_UPDATER.getAndSet(this, null);
 136         checkState(wasReady != null, "Transaction %s is no longer open", getIdentifier());
 137
 138         LOG.debug("Store transaction: {} : Ready", getIdentifier());
 139
 140         final DataTreeModification tree = mutableTree;
 141         TREE_UPDATER.lazySet(this, null);
 142         try {
 143             tree.ready();
 144             return wasReady.transactionReady(this, tree, null);
 145         } catch (RuntimeException e) {
 146             LOG.debug("Store transaction: {}: unexpected failure when readying", getIdentifier(), e);
 147             return wasReady.transactionReady(this, tree, e);
 148         }
 149     }
 150
 151     @Override
 152     public void close() {
 153         @SuppressWarnings("unchecked")
 154         final TransactionReadyPrototype<T> wasReady = READY_UPDATER.getAndSet(this, null);
 155         if (wasReady != null) {
 156             LOG.debug("Store transaction: {} : Closed", getIdentifier());
 157             TREE_UPDATER.lazySet(this, null);
 158             wasReady.transactionAborted(this);
 159         } else {
 160             LOG.debug("Store transaction: {} : Closed after submit", getIdentifier());
 161         }
 162     }
 163
 164     @Override
 165     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 166         return toStringHelper.add("ready", readyImpl == null);
 167     }
 168
 169     /**
 170      * This class is intended to be implemented by Transaction factories
 171      * responsible for allocation of {@link org.opendaylight.controller.sal.core.spi.data.SnapshotBackedWriteTransaction} and
 172      * providing underlying logic for applying implementation.
 173      *
 174      * @param <T> identifier type
 175      */
 176     public abstract static class TransactionReadyPrototype<T> {
 177         /**
 178          * Called when a transaction is closed without being readied. This is not invoked for
 179          * transactions which are ready.
 180          *
 181          * @param tx Transaction which got aborted.
 182          */
 183         protected abstract void transactionAborted(final SnapshotBackedWriteTransaction<T> tx);
 184
 185         /**
 186          * Returns a commit coordinator associated with supplied transactions.
 187          *
 188          * This call must not fail.
 189          *
 190          * @param tx
 191          *            Transaction on which ready was invoked.
 192          * @param tree
 193          *            Modified data tree which has been constructed.
 194          * @param readyError
 195          *            Any error that has already happened when readying.
 196          * @return DOMStoreThreePhaseCommitCohort associated with transaction
 197          */
 198         protected abstract DOMStoreThreePhaseCommitCohort transactionReady(SnapshotBackedWriteTransaction<T> tx,
 199                                                                            DataTreeModification tree,
 200                                                                            @Nullable Exception readyError);
 201     }
 202 }