opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/LocalReadOnlyProxyTransaction.java

   1 /*
   2  * Copyright (c) 2016 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.cluster.databroker.actors.dds;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.base.Verify;
  12 import java.util.function.Consumer;
  13 import javax.annotation.concurrent.NotThreadSafe;
  14 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  15 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  16 import org.opendaylight.controller.cluster.access.commands.PersistenceProtocol;
  17 import org.opendaylight.controller.cluster.access.concepts.Response;
  18 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  19 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  20 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  21 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  22
  23 /**
  24  * A read-only specialization of {@link LocalProxyTransaction}.
  25  *
  26  * @author Robert Varga
  27  */
  28 @NotThreadSafe
  29 final class LocalReadOnlyProxyTransaction extends LocalProxyTransaction {
  30
  31     private final DataTreeSnapshot snapshot;
  32
  33     LocalReadOnlyProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier,
  34         final DataTreeSnapshot snapshot) {
  35         super(parent, identifier, false);
  36         this.snapshot = Preconditions.checkNotNull(snapshot);
  37     }
  38
  39     LocalReadOnlyProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier) {
  40         super(parent, identifier, true);
  41         // It is an error to touch snapshot once we are DONE
  42         this.snapshot = null;
  43     }
  44
  45     @Override
  46     boolean isSnapshotOnly() {
  47         return true;
  48     }
  49
  50     @Override
  51     DataTreeSnapshot readOnlyView() {
  52         return Preconditions.checkNotNull(snapshot, "Transaction %s is DONE", getIdentifier());
  53     }
  54
  55     @Override
  56     void doDelete(final YangInstanceIdentifier path) {
  57         throw new UnsupportedOperationException("Read-only snapshot");
  58     }
  59
  60     @Override
  61     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  62         throw new UnsupportedOperationException("Read-only snapshot");
  63     }
  64
  65     @Override
  66     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  67         throw new UnsupportedOperationException("Read-only snapshot");
  68     }
  69
  70     @Override
  71     CommitLocalTransactionRequest commitRequest(final boolean coordinated) {
  72         throw new UnsupportedOperationException("Read-only snapshot");
  73     }
  74
  75     @Override
  76     void flushState(final AbstractProxyTransaction successor) {
  77         // No-op
  78     }
  79
  80     @Override
  81     void applyForwardedModifyTransactionRequest(final ModifyTransactionRequest request,
  82             final Consumer<Response<?, ?>> callback) {
  83         commonModifyTransactionRequest(request);
  84         abort();
  85     }
  86
  87     @Override
  88     void replayModifyTransactionRequest(final ModifyTransactionRequest request,
  89             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
  90         commonModifyTransactionRequest(request);
  91         enqueueAbort(callback, enqueuedTicks);
  92     }
  93
  94     private static void commonModifyTransactionRequest(final ModifyTransactionRequest request) {
  95         Verify.verify(request.getModifications().isEmpty());
  96
  97         final PersistenceProtocol protocol = request.getPersistenceProtocol().get();
  98         Verify.verify(protocol == PersistenceProtocol.ABORT);
  99     }
 100 }