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 java.util.concurrent.locks.ReadWriteLock;
  11 import java.util.concurrent.locks.ReentrantReadWriteLock;
  12
  13 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  14 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  15 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  16 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  17 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  18 import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
  19 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
  20 import org.opendaylight.yangtools.yang.data.impl.schema.tree.RootModificationApplyOperation.LatestOperationHolder;
  21 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  22 import org.slf4j.Logger;
  23 import org.slf4j.LoggerFactory;
  24
  25 import com.google.common.base.Optional;
  26 import com.google.common.base.Preconditions;
  27
  28 /**
  29  * Read-only snapshot of the data tree.
  30  */
  31 final class InMemoryDataTree implements DataTree {
  32     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTree.class);
  33     private static final YangInstanceIdentifier PUBLIC_ROOT_PATH = YangInstanceIdentifier.builder().build();
  34
  35     private final ReadWriteLock rwLock = new ReentrantReadWriteLock(true);
  36     private final LatestOperationHolder operationHolder = new LatestOperationHolder();
  37     private SchemaContext currentSchemaContext;
  38     private TreeNode rootNode;
  39
  40     public InMemoryDataTree(final TreeNode rootNode, final SchemaContext schemaContext) {
  41         this.rootNode = Preconditions.checkNotNull(rootNode);
  42
  43         if (schemaContext != null) {
  44             // Also sets applyOper
  45             setSchemaContext(schemaContext);
  46         }
  47     }
  48
  49     @Override
  50     public synchronized void setSchemaContext(final SchemaContext newSchemaContext) {
  51         Preconditions.checkNotNull(newSchemaContext);
  52
  53         LOG.info("Attempting to install schema contexts");
  54         LOG.debug("Following schema contexts will be attempted {}",newSchemaContext);
  55
  56         /*
  57          * FIXME: we should walk the schema contexts, both current and new and see
  58          *        whether they are compatible here. Reject incompatible changes.
  59          */
  60
  61         // Instantiate new apply operation, this still may fail
  62         final ModificationApplyOperation newApplyOper = SchemaAwareApplyOperation.from(newSchemaContext);
  63
  64         // Ready to change the context now, make sure no operations are running
  65         rwLock.writeLock().lock();
  66         try {
  67             this.operationHolder.setCurrent(newApplyOper);
  68             this.currentSchemaContext = newSchemaContext;
  69         } finally {
  70             rwLock.writeLock().unlock();
  71         }
  72     }
  73
  74     @Override
  75     public InMemoryDataTreeSnapshot takeSnapshot() {
  76         rwLock.readLock().lock();
  77         try {
  78             return new InMemoryDataTreeSnapshot(currentSchemaContext, rootNode, operationHolder.newSnapshot());
  79         } finally {
  80             rwLock.readLock().unlock();
  81         }
  82     }
  83
  84     @Override
  85     public void validate(final DataTreeModification modification) throws DataValidationFailedException {
  86         Preconditions.checkArgument(modification instanceof InMemoryDataTreeModification, "Invalid modification class %s", modification.getClass());
  87
  88         final InMemoryDataTreeModification m = (InMemoryDataTreeModification)modification;
  89         m.getStrategy().checkApplicable(PUBLIC_ROOT_PATH, m.getRootModification(), Optional.<TreeNode>of(rootNode));
  90     }
  91
  92     @Override
  93     public synchronized DataTreeCandidate prepare(final DataTreeModification modification) {
  94         Preconditions.checkArgument(modification instanceof InMemoryDataTreeModification, "Invalid modification class %s", modification.getClass());
  95
  96         final InMemoryDataTreeModification m = (InMemoryDataTreeModification)modification;
  97         final ModifiedNode root = m.getRootModification();
  98
  99         if (root.getType() == ModificationType.UNMODIFIED) {
 100             return new NoopDataTreeCandidate(PUBLIC_ROOT_PATH, root);
 101         }
 102
 103         rwLock.writeLock().lock();
 104         try {
 105             final Optional<TreeNode> newRoot = m.getStrategy().apply(m.getRootModification(),
 106                     Optional.<TreeNode>of(rootNode), m.getVersion());
 107             Preconditions.checkState(newRoot.isPresent(), "Apply strategy failed to produce root node");
 108             return new InMemoryDataTreeCandidate(PUBLIC_ROOT_PATH, root, rootNode, newRoot.get());
 109         } finally {
 110             rwLock.writeLock().unlock();
 111         }
 112     }
 113
 114     @Override
 115     public synchronized void commit(final DataTreeCandidate candidate) {
 116         if (candidate instanceof NoopDataTreeCandidate) {
 117             return;
 118         }
 119
 120         Preconditions.checkArgument(candidate instanceof InMemoryDataTreeCandidate, "Invalid candidate class %s", candidate.getClass());
 121         final InMemoryDataTreeCandidate c = (InMemoryDataTreeCandidate)candidate;
 122
 123         LOG.debug("Updating datastore from {} to {}", rootNode, c.getAfterRoot());
 124
 125         if (LOG.isTraceEnabled()) {
 126             LOG.trace("Data Tree is {}", StoreUtils.toStringTree(c.getAfterRoot().getData()));
 127         }
 128
 129         // Ready to change the context now, make sure no operations are running
 130         rwLock.writeLock().lock();
 131         try {
 132             Preconditions.checkState(c.getBeforeRoot() == rootNode,
 133                     String.format("Store tree %s and candidate base %s differ.", rootNode, c.getBeforeRoot()));
 134             this.rootNode = c.getAfterRoot();
 135         } finally {
 136             rwLock.writeLock().unlock();
 137         }
 138     }
 139 }