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 org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  14 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes;
  15 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  16 import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree;
  17 import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
  18 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
  19 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextNode;
  20 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextTree;
  21 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  22 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
  23 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  24 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  25 import org.slf4j.Logger;
  26 import org.slf4j.LoggerFactory;
  27
  28 /**
  29  * Read-only snapshot of the data tree.
  30  */
  31 final class InMemoryDataTree extends AbstractDataTreeTip implements TipProducingDataTree {
  32     private static final AtomicReferenceFieldUpdater<InMemoryDataTree, DataTreeState> STATE_UPDATER =
  33             AtomicReferenceFieldUpdater.newUpdater(InMemoryDataTree.class, DataTreeState.class, "state");
  34     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTree.class);
  35
  36     private final YangInstanceIdentifier rootPath;
  37     private final TreeType treeType;
  38
  39     /**
  40      * Current data store state generation.
  41      */
  42     private volatile DataTreeState state;
  43
  44     public InMemoryDataTree(final TreeNode rootNode, final TreeType treeType, final YangInstanceIdentifier rootPath, final SchemaContext schemaContext) {
  45         this.treeType = Preconditions.checkNotNull(treeType, "treeType");
  46         this.rootPath = Preconditions.checkNotNull(rootPath, "rootPath");
  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(rootPath);
  65         if (rootContextNode == null) {
  66             LOG.debug("Could not find root {} in new schema context, not upgrading", rootPath);
  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", rootPath, 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, treeType);
  80         } else {
  81             rootNode = SchemaAwareApplyOperation.from(rootSchemaNode, treeType);
  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             Preconditions.checkState(oldRoot == currentRoot, "Store tree %s and candidate base %s differ.", currentRoot, oldRoot);
 117
 118             newState = currentState.withRoot(newRoot);
 119             LOG.trace("Updated state from {} to {}", currentState, newState);
 120         } while (!STATE_UPDATER.compareAndSet(this, currentState, newState));
 121     }
 122
 123     @Override
 124     public YangInstanceIdentifier getRootPath() {
 125         return rootPath;
 126     }
 127
 128     @Override
 129     public String toString() {
 130         return MoreObjects.toStringHelper(this).
 131                 add("object", super.toString()).
 132                 add("rootPath", rootPath).
 133                 add("state", state).
 134                 toString();
 135     }
 136
 137     @Override
 138     protected TreeNode getTipRoot() {
 139         return state.getRoot();
 140     }
 141 }