dom/mdsal-dom-spi/src/main/java/org/opendaylight/mdsal/dom/spi/store/SnapshotBackedReadWriteTransaction.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.checkNotNull;
  11
  12 import com.google.common.annotations.Beta;
  13 import com.google.common.base.Optional;
  14 import com.google.common.util.concurrent.CheckedFuture;
  15 import com.google.common.util.concurrent.Futures;
  16 import org.opendaylight.mdsal.common.api.ReadFailedException;
  17 import org.opendaylight.mdsal.dom.spi.store.SnapshotBackedWriteTransaction.TransactionReadyPrototype;
  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.DataTreeSnapshot;
  21 import org.slf4j.Logger;
  22 import org.slf4j.LoggerFactory;
  23
  24 /**
  25  * Implementation of Read-Write transaction which is backed by {@link DataTreeSnapshot}
  26  * and executed according to {@link TransactionReadyPrototype}.
  27  *
  28  * @param <T> identifier type
  29  */
  30 @Beta
  31 public final class SnapshotBackedReadWriteTransaction<T> extends
  32         SnapshotBackedWriteTransaction<T> implements DOMStoreReadWriteTransaction {
  33     private static final Logger LOG = LoggerFactory.getLogger(SnapshotBackedReadWriteTransaction.class);
  34
  35     SnapshotBackedReadWriteTransaction(final T identifier, final boolean debug,
  36             final DataTreeSnapshot snapshot, final TransactionReadyPrototype<T> readyImpl) {
  37         super(identifier, debug, snapshot, readyImpl);
  38     }
  39
  40     @SuppressWarnings("checkstyle:IllegalCatch")
  41     @Override
  42     public CheckedFuture<Optional<NormalizedNode<?,?>>, ReadFailedException> read(final YangInstanceIdentifier path) {
  43         LOG.debug("Tx: {} Read: {}", getIdentifier(), path);
  44         checkNotNull(path, "Path must not be null.");
  45
  46         final Optional<NormalizedNode<?, ?>> result;
  47
  48         try {
  49             result = readSnapshotNode(path);
  50         } catch (Exception e) {
  51             LOG.error("Tx: {} Failed Read of {}", getIdentifier(), path, e);
  52             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Read failed", e));
  53         }
  54
  55         if (result == null) {
  56             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Transaction is closed"));
  57         } else {
  58             return Futures.immediateCheckedFuture(result);
  59         }
  60     }
  61
  62     @SuppressWarnings("checkstyle:IllegalCatch")
  63     @Override
  64     public CheckedFuture<Boolean, ReadFailedException> exists(final YangInstanceIdentifier path) {
  65         try {
  66             return Futures.immediateCheckedFuture(read(path).checkedGet().isPresent());
  67         } catch (ReadFailedException e) {
  68             return Futures.immediateFailedCheckedFuture(e);
  69         }
  70     }
  71 }