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 static com.google.common.base.Preconditions.checkNotNull;
  11 import static com.google.common.base.Verify.verify;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import java.util.Optional;
  15 import java.util.function.Consumer;
  16 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  17 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  18 import org.opendaylight.controller.cluster.access.commands.PersistenceProtocol;
  19 import org.opendaylight.controller.cluster.access.concepts.Response;
  20 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  21 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  22 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  23 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeSnapshot;
  24
  25 /**
  26  * A read-only specialization of {@link LocalProxyTransaction}. This class is NOT thread-safe.
  27  *
  28  * @author Robert Varga
  29  */
  30 final class LocalReadOnlyProxyTransaction extends LocalProxyTransaction {
  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 = requireNonNull(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         snapshot = null;
  43     }
  44
  45     @Override
  46     boolean isSnapshotOnly() {
  47         return true;
  48     }
  49
  50     @Override
  51     DataTreeSnapshot readOnlyView() {
  52         return checkNotNull(snapshot, "Transaction %s is DONE", getIdentifier());
  53     }
  54
  55     @Override
  56     void doDelete(final YangInstanceIdentifier path) {
  57         throw new UnsupportedOperationException("doDelete");
  58     }
  59
  60     @Override
  61     void doMerge(final YangInstanceIdentifier path, final NormalizedNode data) {
  62         throw new UnsupportedOperationException("doMerge");
  63     }
  64
  65     @Override
  66     void doWrite(final YangInstanceIdentifier path, final NormalizedNode data) {
  67         throw new UnsupportedOperationException("doWrite");
  68     }
  69
  70     @Override
  71     CommitLocalTransactionRequest commitRequest(final boolean coordinated) {
  72         throw new UnsupportedOperationException("commitRequest");
  73     }
  74
  75     @Override
  76     Optional<ModifyTransactionRequest> flushState() {
  77         // No-op
  78         return Optional.empty();
  79     }
  80
  81     @Override
  82     void applyForwardedModifyTransactionRequest(final ModifyTransactionRequest request,
  83             final Consumer<Response<?, ?>> callback) {
  84         commonModifyTransactionRequest(request);
  85         abort();
  86     }
  87
  88     @Override
  89     void replayModifyTransactionRequest(final ModifyTransactionRequest request,
  90             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
  91         commonModifyTransactionRequest(request);
  92         enqueueAbort(callback, enqueuedTicks);
  93     }
  94
  95     private static void commonModifyTransactionRequest(final ModifyTransactionRequest request) {
  96         verify(request.getModifications().isEmpty());
  97
  98         final PersistenceProtocol protocol = request.getPersistenceProtocol().get();
  99         verify(protocol == PersistenceProtocol.ABORT);
 100     }
 101 }