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