dom/mdsal-dom-spi/src/main/java/org/opendaylight/mdsal/dom/spi/store/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.mdsal.dom.spi.store;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import com.google.common.annotations.Beta;
  14 import com.google.common.base.MoreObjects.ToStringHelper;
  15 import com.google.common.base.Throwables;
  16 import java.util.Optional;
  17 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
  18 import org.eclipse.jdt.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 {@link DataTreeSnapshot} and executed according to
  28  * {@link TransactionReadyPrototype}.
  29  *
  30  * @param <T> Identifier type
  31  */
  32 @Beta
  33 public class SnapshotBackedWriteTransaction<T> extends AbstractDOMStoreTransaction<T>
  34         implements DOMStoreWriteTransaction, SnapshotBackedTransaction {
  35
  36     private static final Logger LOG = LoggerFactory.getLogger(SnapshotBackedWriteTransaction.class);
  37
  38     @SuppressWarnings("rawtypes")
  39     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction,
  40         TransactionReadyPrototype> READY_UPDATER =
  41             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class,
  42                     TransactionReadyPrototype.class, "readyImpl");
  43
  44     @SuppressWarnings("rawtypes")
  45     private static final AtomicReferenceFieldUpdater<SnapshotBackedWriteTransaction,
  46         DataTreeModification> TREE_UPDATER =
  47             AtomicReferenceFieldUpdater.newUpdater(SnapshotBackedWriteTransaction.class,
  48                     DataTreeModification.class, "mutableTree");
  49
  50     // non-null when not ready
  51     private volatile TransactionReadyPrototype<T> readyImpl;
  52     // non-null when not committed/closed
  53     private volatile DataTreeModification mutableTree;
  54
  55     SnapshotBackedWriteTransaction(final T identifier, final boolean debug,
  56             final DataTreeSnapshot snapshot, final TransactionReadyPrototype<T> readyImpl) {
  57         super(identifier, debug);
  58         this.readyImpl = requireNonNull(readyImpl, "readyImpl must not be null.");
  59         mutableTree = snapshot.newModification();
  60         LOG.debug("Write Tx: {} allocated with snapshot {}", identifier, snapshot);
  61     }
  62
  63     @SuppressWarnings("checkstyle:IllegalCatch")
  64     @Override
  65     public void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  66         checkNotReady();
  67
  68         final DataTreeModification tree = mutableTree;
  69         LOG.debug("Tx: {} Write: {}:{}", getIdentifier(), path, data);
  70
  71         try {
  72             tree.write(path, data);
  73             // FIXME: Add checked exception
  74         } catch (Exception e) {
  75             LOG.error("Tx: {}, failed to write {}:{} in {}", getIdentifier(), path, data, tree, e);
  76             // Rethrow original ones if they are subclasses of RuntimeException or Error
  77             Throwables.throwIfUnchecked(e);
  78             // FIXME: Introduce proper checked exception
  79             throw new IllegalArgumentException("Illegal input data.", e);
  80         }
  81     }
  82
  83     @SuppressWarnings("checkstyle:IllegalCatch")
  84     @Override
  85     public void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  86         checkNotReady();
  87
  88         final DataTreeModification tree = mutableTree;
  89         LOG.debug("Tx: {} Merge: {}:{}", getIdentifier(), path, data);
  90
  91         try {
  92             tree.merge(path, data);
  93             // FIXME: Add checked exception
  94         } catch (Exception e) {
  95             LOG.error("Tx: {}, failed to merge {}:{} in {}", getIdentifier(), path, data, tree, e);
  96             // Rethrow original ones if they are subclasses of RuntimeException or Error
  97             Throwables.throwIfUnchecked(e);
  98             // FIXME: Introduce proper checked exception
  99             throw new IllegalArgumentException("Illegal input data.", e);
 100         }
 101     }
 102
 103     @SuppressWarnings("checkstyle:IllegalCatch")
 104     @Override
 105     public void delete(final YangInstanceIdentifier path) {
 106         checkNotReady();
 107
 108         final DataTreeModification tree = mutableTree;
 109         LOG.debug("Tx: {} Delete: {}", getIdentifier(), path);
 110
 111         try {
 112             tree.delete(path);
 113             // FIXME: Add checked exception
 114         } catch (Exception e) {
 115             LOG.error("Tx: {}, failed to delete {} in {}", getIdentifier(), path, tree, e);
 116             // Rethrow original ones if they are subclasses of RuntimeException or Error
 117             Throwables.throwIfUnchecked(e);
 118             // FIXME: Introduce proper checked exception
 119             throw new IllegalArgumentException("Illegal path to delete.", e);
 120         }
 121     }
 122
 123     /**
 124      * Exposed for {@link SnapshotBackedReadWriteTransaction}'s sake only. The contract does
 125      * not allow data access after the transaction has been closed or readied.
 126      *
 127      * @param path Path to read
 128      * @return null if the the transaction has been closed;
 129      */
 130     final Optional<NormalizedNode<?, ?>> readSnapshotNode(final YangInstanceIdentifier path) {
 131         return readyImpl == null ? null : mutableTree.readNode(path);
 132     }
 133
 134     private void checkNotReady() {
 135         checkState(readyImpl != null,
 136                 "Transaction %s is no longer open. No further modifications allowed.", getIdentifier());
 137     }
 138
 139     @SuppressWarnings("checkstyle:IllegalCatch")
 140     @Override
 141     public DOMStoreThreePhaseCommitCohort ready() {
 142         @SuppressWarnings("unchecked")
 143         final TransactionReadyPrototype<T> wasReady = READY_UPDATER.getAndSet(this, null);
 144         checkState(wasReady != null, "Transaction %s is no longer open", getIdentifier());
 145
 146         LOG.debug("Store transaction: {} : Ready", getIdentifier());
 147
 148         final DataTreeModification tree = mutableTree;
 149         TREE_UPDATER.lazySet(this, null);
 150         try {
 151             tree.ready();
 152             return wasReady.transactionReady(this, tree, null);
 153         } catch (RuntimeException e) {
 154             LOG.debug("Store transaction: {}: unexpected failure when readying", getIdentifier(), e);
 155             return wasReady.transactionReady(this, tree, e);
 156         }
 157     }
 158
 159     @Override
 160     public void close() {
 161         @SuppressWarnings("unchecked")
 162         final TransactionReadyPrototype<T> wasReady = READY_UPDATER.getAndSet(this, null);
 163         if (wasReady != null) {
 164             LOG.debug("Store transaction: {} : Closed", getIdentifier());
 165             TREE_UPDATER.lazySet(this, null);
 166             wasReady.transactionAborted(this);
 167         } else {
 168             LOG.debug("Store transaction: {} : Closed after submit", getIdentifier());
 169         }
 170     }
 171
 172     @Override
 173     public Optional<DataTreeSnapshot> getSnapshot() {
 174         return readyImpl == null ? Optional.empty() : Optional.ofNullable(mutableTree);
 175     }
 176
 177     @Override
 178     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 179         return toStringHelper.add("ready", readyImpl == null);
 180     }
 181
 182     /**
 183      * Prototype implementation of {@link SnapshotBackedWriteTransaction#ready()}.
 184      *
 185      * <p>
 186      * This class is intended to be implemented by Transaction factories responsible for allocation
 187      * of {@link org.opendaylight.mdsal.dom.spi.store.SnapshotBackedWriteTransaction} and
 188      * providing underlying logic for applying implementation.
 189      *
 190      * @param <T> identifier type
 191      */
 192     public abstract static class TransactionReadyPrototype<T> {
 193         /**
 194          * Called when a transaction is closed without being readied. This is not invoked for
 195          * transactions which are ready.
 196          *
 197          * @param tx Transaction which got aborted.
 198          */
 199         protected abstract void transactionAborted(SnapshotBackedWriteTransaction<T> tx);
 200
 201         /**
 202          * Returns a commit coordinator associated with supplied transactions.
 203          * This call must not fail.
 204          *
 205          * @param tx
 206          *            Transaction on which ready was invoked.
 207          * @param tree
 208          *            Modified data tree which has been constructed.
 209          * @param readyError
 210          *            Any error that has already happened when readying.
 211          * @return DOMStoreThreePhaseCommitCohort associated with transaction
 212          */
 213         protected abstract DOMStoreThreePhaseCommitCohort transactionReady(SnapshotBackedWriteTransaction<T> tx,
 214                                                                            DataTreeModification tree,
 215                                                                            @Nullable Exception readyError);
 216     }
 217 }