opendaylight/md-sal/sal-dom-broker/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/tree/data/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.controller.md.sal.dom.store.impl.tree.data;
   9
  10 import java.util.concurrent.locks.ReadWriteLock;
  11 import java.util.concurrent.locks.ReentrantReadWriteLock;
  12
  13 import org.opendaylight.controller.md.sal.dom.store.impl.tree.DataPreconditionFailedException;
  14 import org.opendaylight.controller.md.sal.dom.store.impl.tree.DataTree;
  15 import org.opendaylight.controller.md.sal.dom.store.impl.tree.DataTreeCandidate;
  16 import org.opendaylight.controller.md.sal.dom.store.impl.tree.DataTreeModification;
  17 import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreUtils;
  18 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  19 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  20 import org.slf4j.Logger;
  21 import org.slf4j.LoggerFactory;
  22
  23 import com.google.common.base.Optional;
  24 import com.google.common.base.Preconditions;
  25
  26 /**
  27  * Read-only snapshot of the data tree.
  28  */
  29 final class InMemoryDataTree implements DataTree {
  30     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTree.class);
  31     private static final InstanceIdentifier PUBLIC_ROOT_PATH = InstanceIdentifier.builder().build();
  32
  33     private final ReadWriteLock rwLock = new ReentrantReadWriteLock(true);
  34     private StoreMetadataNode rootNode;
  35     private SchemaContext currentSchemaContext;
  36
  37     public InMemoryDataTree(StoreMetadataNode rootNode, final SchemaContext schemaContext) {
  38         this.rootNode = Preconditions.checkNotNull(rootNode);
  39         this.currentSchemaContext = schemaContext;
  40     }
  41
  42     @Override
  43         public synchronized void setSchemaContext(final SchemaContext newSchemaContext) {
  44         Preconditions.checkNotNull(newSchemaContext);
  45
  46         LOG.info("Attepting to install schema context {}", newSchemaContext);
  47
  48         /*
  49          * FIXME: we should walk the schema contexts, both current and new and see
  50          *        whether they are compatible here. Reject incompatible changes.
  51          */
  52
  53         // Ready to change the context now, make sure no operations are running
  54         rwLock.writeLock().lock();
  55         try {
  56             this.currentSchemaContext = newSchemaContext;
  57         } finally {
  58             rwLock.writeLock().unlock();
  59         }
  60     }
  61
  62     @Override
  63         public InMemoryDataTreeSnapshot takeSnapshot() {
  64         rwLock.readLock().lock();
  65         try {
  66             return new InMemoryDataTreeSnapshot(currentSchemaContext, rootNode);
  67         } finally {
  68             rwLock.readLock().unlock();
  69         }
  70     }
  71
  72         @Override
  73         public void validate(DataTreeModification modification) throws DataPreconditionFailedException {
  74                 Preconditions.checkArgument(modification instanceof InMemoryDataTreeModification, "Invalid modification class %s", modification.getClass());
  75
  76                 final InMemoryDataTreeModification m = (InMemoryDataTreeModification)modification;
  77                 m.getStrategy().checkApplicable(PUBLIC_ROOT_PATH, m.getRootModification(), Optional.of(rootNode));
  78         }
  79
  80         @Override
  81         public synchronized DataTreeCandidate prepare(DataTreeModification modification) {
  82                 Preconditions.checkArgument(modification instanceof InMemoryDataTreeModification, "Invalid modification class %s", modification.getClass());
  83
  84                 final InMemoryDataTreeModification m = (InMemoryDataTreeModification)modification;
  85                 final NodeModification root = m.getRootModification();
  86
  87         if (root.getModificationType() == ModificationType.UNMODIFIED) {
  88                 return new NoopDataTreeCandidate(PUBLIC_ROOT_PATH, root);
  89         }
  90
  91         rwLock.writeLock().lock();
  92         try {
  93                 // FIXME: rootNode needs to be a read-write snapshot here...
  94                 final Optional<StoreMetadataNode> newRoot = m.getStrategy().apply(m.getRootModification(), Optional.of(rootNode), StoreUtils.increase(rootNode.getSubtreeVersion()));
  95                 Preconditions.checkState(newRoot.isPresent(), "Apply strategy failed to produce root node");
  96                 return new InMemoryDataTreeCandidate(PUBLIC_ROOT_PATH, root, rootNode, newRoot.get());
  97         } finally {
  98                 rwLock.writeLock().unlock();
  99         }
 100         }
 101
 102         @Override
 103         public synchronized void commit(DataTreeCandidate candidate) {
 104                 if (candidate instanceof NoopDataTreeCandidate) {
 105                         return;
 106                 }
 107
 108                 Preconditions.checkArgument(candidate instanceof InMemoryDataTreeCandidate, "Invalid candidate class %s", candidate.getClass());
 109                 final InMemoryDataTreeCandidate c = (InMemoryDataTreeCandidate)candidate;
 110
 111         LOG.debug("Updating Store snapshot version: {} with version:{}", rootNode.getSubtreeVersion(), c.getAfterRoot().getSubtreeVersion());
 112
 113         if (LOG.isTraceEnabled()) {
 114             LOG.trace("Data Tree is {}", StoreUtils.toStringTree(c.getAfterRoot().getData()));
 115         }
 116
 117         // Ready to change the context now, make sure no operations are running
 118         rwLock.writeLock().lock();
 119         try {
 120             Preconditions.checkState(c.getBeforeRoot() == rootNode,
 121                     String.format("Store snapshot %s and transaction snapshot %s differ.", rootNode, c.getBeforeRoot()));
 122             this.rootNode = c.getAfterRoot();
 123         } finally {
 124             rwLock.writeLock().unlock();
 125         }
 126         }
 127 }