yang/yang-data-impl/src/main/java/org/opendaylight/yangtools/yang/data/impl/schema/tree/InMemoryDataTree.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.yangtools.yang.data.impl.schema.tree;
   9
  10 import com.google.common.base.MoreObjects;
  11 import com.google.common.base.Preconditions;
  12 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
  13 import javax.annotation.Nonnull;
  14 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  15 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes;
  16 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  17 import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree;
  18 import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
  19 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
  20 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextNode;
  21 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextTree;
  22 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  23 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
  24 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  25 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  26 import org.slf4j.Logger;
  27 import org.slf4j.LoggerFactory;
  28
  29 /**
  30  * Read-only snapshot of the data tree.
  31  */
  32 final class InMemoryDataTree extends AbstractDataTreeTip implements TipProducingDataTree {
  33     private static final AtomicReferenceFieldUpdater<InMemoryDataTree, DataTreeState> STATE_UPDATER =
  34             AtomicReferenceFieldUpdater.newUpdater(InMemoryDataTree.class, DataTreeState.class, "state");
  35     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTree.class);
  36
  37     private final YangInstanceIdentifier rootPath;
  38     private final TreeType treeType;
  39
  40     /**
  41      * Current data store state generation.
  42      */
  43     private volatile DataTreeState state;
  44
  45     public InMemoryDataTree(final TreeNode rootNode, final TreeType treeType, final YangInstanceIdentifier rootPath, final SchemaContext schemaContext) {
  46         this.treeType = Preconditions.checkNotNull(treeType, "treeType");
  47         this.rootPath = Preconditions.checkNotNull(rootPath, "rootPath");
  48         state = DataTreeState.createInitial(rootNode);
  49         if (schemaContext != null) {
  50             setSchemaContext(schemaContext);
  51         }
  52     }
  53
  54     /*
  55      * This method is synchronized to guard against user attempting to install
  56      * multiple contexts. Otherwise it runs in a lock-free manner.
  57      */
  58     @Override
  59     public synchronized void setSchemaContext(final SchemaContext newSchemaContext) {
  60         Preconditions.checkNotNull(newSchemaContext);
  61
  62         LOG.debug("Following schema contexts will be attempted {}", newSchemaContext);
  63
  64         final DataSchemaContextTree contextTree = DataSchemaContextTree.from(newSchemaContext);
  65         final DataSchemaContextNode<?> rootContextNode = contextTree.getChild(rootPath);
  66         if (rootContextNode == null) {
  67             LOG.debug("Could not find root {} in new schema context, not upgrading", rootPath);
  68             return;
  69         }
  70
  71         final DataSchemaNode rootSchemaNode = rootContextNode.getDataSchemaNode();
  72         if (!(rootSchemaNode instanceof DataNodeContainer)) {
  73             LOG.warn("Root {} resolves to non-container type {}, not upgrading", rootPath, rootSchemaNode);
  74             return;
  75         }
  76
  77         final ModificationApplyOperation rootNode;
  78         if (rootSchemaNode instanceof ContainerSchemaNode) {
  79             // FIXME: real root needs to enfore presence, but that require pre-population
  80             rootNode = new ContainerModificationStrategy((ContainerSchemaNode) rootSchemaNode, treeType);
  81         } else {
  82             rootNode = SchemaAwareApplyOperation.from(rootSchemaNode, treeType);
  83         }
  84
  85         DataTreeState currentState, newState;
  86         do {
  87             currentState = state;
  88             newState = currentState.withSchemaContext(newSchemaContext, rootNode);
  89         } while (!STATE_UPDATER.compareAndSet(this, currentState, newState));
  90     }
  91
  92     @Override
  93     public InMemoryDataTreeSnapshot takeSnapshot() {
  94         return state.newSnapshot();
  95     }
  96
  97     @Override
  98     public void commit(final DataTreeCandidate candidate) {
  99         if (candidate instanceof NoopDataTreeCandidate) {
 100             return;
 101         }
 102         Preconditions.checkArgument(candidate instanceof InMemoryDataTreeCandidate, "Invalid candidate class %s", candidate.getClass());
 103         final InMemoryDataTreeCandidate c = (InMemoryDataTreeCandidate)candidate;
 104
 105         if (LOG.isTraceEnabled()) {
 106             LOG.trace("Data Tree is {}", NormalizedNodes.toStringTree(c.getTipRoot().getData()));
 107         }
 108
 109         final TreeNode newRoot = c.getTipRoot();
 110         DataTreeState currentState, newState;
 111         do {
 112             currentState = state;
 113             final TreeNode currentRoot = currentState.getRoot();
 114             LOG.debug("Updating datastore from {} to {}", currentRoot, newRoot);
 115
 116             final TreeNode oldRoot = c.getBeforeRoot();
 117             if (oldRoot != currentRoot) {
 118                 final String oldStr = simpleToString(oldRoot);
 119                 final String currentStr = simpleToString(currentRoot);
 120                 throw new IllegalStateException("Store tree " + currentStr + " and candidate base " + oldStr + " differ.");
 121             }
 122
 123             newState = currentState.withRoot(newRoot);
 124             LOG.trace("Updated state from {} to {}", currentState, newState);
 125         } while (!STATE_UPDATER.compareAndSet(this, currentState, newState));
 126     }
 127
 128     private static String simpleToString(final Object o) {
 129         return o.getClass().getName() + "@" + Integer.toHexString(o.hashCode());
 130     }
 131
 132     @Override
 133     public YangInstanceIdentifier getRootPath() {
 134         return rootPath;
 135     }
 136
 137     @Override
 138     public String toString() {
 139         return MoreObjects.toStringHelper(this).
 140                 add("object", super.toString()).
 141                 add("rootPath", rootPath).
 142                 add("state", state).
 143                 toString();
 144     }
 145
 146     @Override
 147     @Nonnull
 148     protected TreeNode getTipRoot() {
 149         return state.getRoot();
 150     }
 151 }