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