opendaylight/md-sal/sal-dom-broker/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/tree/data/InMemoryDataTreeModification.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.tree.data;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import java.util.Map.Entry;
  13 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
  14
  15 import org.opendaylight.controller.md.sal.dom.store.impl.tree.DataTreeModification;
  16 import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreUtils;
  17 import org.opendaylight.controller.md.sal.dom.store.impl.tree.TreeNodeUtils;
  18 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  19 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
  20 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  21 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodeContainer;
  22 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeUtils;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25
  26 import com.google.common.base.Optional;
  27 import com.google.common.base.Preconditions;
  28
  29 final class InMemoryDataTreeModification implements DataTreeModification {
  30     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTreeModification.class);
  31
  32     /*
  33      * FIXME: the thread safety of concurrent write/delete/read/seal operations
  34      *        needs to be evaluated.
  35      */
  36     private static final AtomicIntegerFieldUpdater<InMemoryDataTreeModification> SEALED_UPDATER =
  37             AtomicIntegerFieldUpdater.newUpdater(InMemoryDataTreeModification.class, "sealed");
  38     private volatile int sealed = 0;
  39
  40     private final ModificationApplyOperation strategyTree;
  41     private final InMemoryDataTreeSnapshot snapshot;
  42     private final NodeModification rootNode;
  43
  44     InMemoryDataTreeModification(final InMemoryDataTreeSnapshot snapshot, final ModificationApplyOperation resolver) {
  45         this.snapshot = Preconditions.checkNotNull(snapshot);
  46         this.strategyTree = Preconditions.checkNotNull(resolver);
  47         this.rootNode = NodeModification.createUnmodified(snapshot.getRootNode());
  48     }
  49
  50     NodeModification getRootModification() {
  51         return rootNode;
  52     }
  53
  54     ModificationApplyOperation getStrategy() {
  55         return strategyTree;
  56     }
  57
  58     @Override
  59     public void write(final InstanceIdentifier path, final NormalizedNode<?, ?> value) {
  60         checkSealed();
  61         resolveModificationFor(path).write(value);
  62     }
  63
  64     @Override
  65     public void merge(final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
  66         checkSealed();
  67         mergeImpl(resolveModificationFor(path),data);
  68     }
  69
  70     private void mergeImpl(final OperationWithModification op,final NormalizedNode<?,?> data) {
  71
  72         if(data instanceof NormalizedNodeContainer<?,?,?>) {
  73             @SuppressWarnings({ "rawtypes", "unchecked" })
  74             NormalizedNodeContainer<?,?,NormalizedNode<PathArgument, ?>> dataContainer = (NormalizedNodeContainer) data;
  75             for(NormalizedNode<PathArgument, ?> child : dataContainer.getValue()) {
  76                 PathArgument childId = child.getIdentifier();
  77                 mergeImpl(op.forChild(childId), child);
  78             }
  79         }
  80         op.merge(data);
  81     }
  82
  83     @Override
  84     public void delete(final InstanceIdentifier path) {
  85         checkSealed();
  86         resolveModificationFor(path).delete();
  87     }
  88
  89     @Override
  90     public Optional<NormalizedNode<?, ?>> readNode(final InstanceIdentifier path) {
  91         Entry<InstanceIdentifier, NodeModification> modification = TreeNodeUtils.findClosestsOrFirstMatch(rootNode, path, NodeModification.IS_TERMINAL_PREDICATE);
  92
  93         Optional<StoreMetadataNode> result = resolveSnapshot(modification);
  94         if (result.isPresent()) {
  95             NormalizedNode<?, ?> data = result.get().getData();
  96             return NormalizedNodeUtils.findNode(modification.getKey(), data, path);
  97         }
  98         return Optional.absent();
  99     }
 100
 101     private Optional<StoreMetadataNode> resolveSnapshot(
 102             final Entry<InstanceIdentifier, NodeModification> keyModification) {
 103         InstanceIdentifier path = keyModification.getKey();
 104         NodeModification modification = keyModification.getValue();
 105         return resolveSnapshot(path, modification);
 106     }
 107
 108     private Optional<StoreMetadataNode> resolveSnapshot(final InstanceIdentifier path,
 109             final NodeModification modification) {
 110         try {
 111             Optional<Optional<StoreMetadataNode>> potentialSnapshot = modification.getSnapshotCache();
 112             if(potentialSnapshot.isPresent()) {
 113                 return potentialSnapshot.get();
 114             }
 115             return resolveModificationStrategy(path).apply(modification, modification.getOriginal(),
 116                     StoreUtils.increase(snapshot.getRootNode().getSubtreeVersion()));
 117         } catch (Exception e) {
 118             LOG.error("Could not create snapshot for {}:{}", path,modification,e);
 119             throw e;
 120         }
 121     }
 122
 123     private ModificationApplyOperation resolveModificationStrategy(final InstanceIdentifier path) {
 124         LOG.trace("Resolving modification apply strategy for {}", path);
 125         return TreeNodeUtils.findNodeChecked(strategyTree, path);
 126     }
 127
 128     private OperationWithModification resolveModificationFor(final InstanceIdentifier path) {
 129         NodeModification modification = rootNode;
 130         // We ensure strategy is present.
 131         ModificationApplyOperation operation = resolveModificationStrategy(path);
 132         for (PathArgument pathArg : path.getPath()) {
 133             modification = modification.modifyChild(pathArg);
 134         }
 135         return OperationWithModification.from(operation, modification);
 136     }
 137
 138     @Override
 139     public void seal() {
 140         final boolean success = SEALED_UPDATER.compareAndSet(this, 0, 1);
 141         Preconditions.checkState(success, "Attempted to seal an already-sealed Data Tree.");
 142         rootNode.seal();
 143     }
 144
 145     private void checkSealed() {
 146         checkState(sealed == 0, "Data Tree is sealed. No further modifications allowed.");
 147     }
 148
 149     @Override
 150     public String toString() {
 151         return "MutableDataTree [modification=" + rootNode + "]";
 152     }
 153
 154     @Override
 155     public DataTreeModification newModification() {
 156         // FIXME: transaction chaining
 157         throw new UnsupportedOperationException("Implement this as part of transaction chaining");
 158     }
 159 }