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