opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/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.controller.md.sal.dom.store.impl;
   9
  10 import static com.google.common.base.Preconditions.checkNotNull;
  11
  12 import com.google.common.base.Optional;
  13 import com.google.common.util.concurrent.CheckedFuture;
  14 import com.google.common.util.concurrent.Futures;
  15
  16 import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
  17 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  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 Read-Write transaction which is backed by {@link DataTreeSnapshot}
  27  * and executed according to {@link TransactionReadyPrototype}.
  28  *
  29  */
  30 class SnapshotBackedReadWriteTransaction extends SnapshotBackedWriteTransaction
  31                                          implements DOMStoreReadWriteTransaction {
  32
  33     private static final Logger LOG = LoggerFactory.getLogger(SnapshotBackedReadWriteTransaction.class);
  34
  35     /**
  36      * Creates new read-write transaction.
  37      *
  38      * @param identifier transaction Identifier
  39      * @param snapshot Snapshot which will be modified.
  40      * @param readyImpl Implementation of ready method.
  41      */
  42     protected SnapshotBackedReadWriteTransaction(final Object identifier, final boolean debug,
  43             final DataTreeSnapshot snapshot, final TransactionReadyPrototype store) {
  44         super(identifier, debug, snapshot, store);
  45     }
  46
  47     @Override
  48     public CheckedFuture<Optional<NormalizedNode<?,?>>, ReadFailedException> read(final YangInstanceIdentifier path) {
  49         LOG.debug("Tx: {} Read: {}", getIdentifier(), path);
  50         checkNotNull(path, "Path must not be null.");
  51
  52         DataTreeModification dataView = getMutatedView();
  53         if(dataView == null) {
  54             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Transaction is closed"));
  55         }
  56
  57         try {
  58             return Futures.immediateCheckedFuture(dataView.readNode(path));
  59         } catch (Exception e) {
  60             LOG.error("Tx: {} Failed Read of {}", getIdentifier(), path, e);
  61             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Read failed",e));
  62         }
  63     }
  64
  65     @Override
  66     public CheckedFuture<Boolean, ReadFailedException> exists(final YangInstanceIdentifier path) {
  67         try {
  68             return Futures.immediateCheckedFuture(
  69                 read(path).checkedGet().isPresent());
  70         } catch (ReadFailedException e) {
  71             return Futures.immediateFailedCheckedFuture(e);
  72         }
  73     }
  74 }