opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/persisted/CommitTransactionPayload.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.datastore.persisted;
   9
  10 import com.google.common.annotations.Beta;
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.io.ByteArrayDataOutput;
  13 import com.google.common.io.ByteStreams;
  14 import java.io.DataInput;
  15 import java.io.Externalizable;
  16 import java.io.IOException;
  17 import java.io.ObjectInput;
  18 import java.io.ObjectOutput;
  19 import java.io.Serializable;
  20 import java.util.AbstractMap.SimpleImmutableEntry;
  21 import java.util.Map.Entry;
  22 import java.util.Optional;
  23 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  24 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  25 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  26
  27 /**
  28  * Payload persisted when a transaction commits. It contains the transaction identifier and the
  29  * {@link DataTreeCandidate}
  30  *
  31  * @author Robert Varga
  32  */
  33 @Beta
  34 public final class CommitTransactionPayload extends Payload implements DataTreeCandidateSupplier, Serializable {
  35     private static final class Proxy implements Externalizable {
  36         private static final long serialVersionUID = 1L;
  37         private byte[] serialized;
  38
  39         public Proxy() {
  40             // For Externalizable
  41         }
  42
  43         Proxy(final byte[] serialized) {
  44             this.serialized = Preconditions.checkNotNull(serialized);
  45         }
  46
  47         @Override
  48         public void writeExternal(final ObjectOutput out) throws IOException {
  49             out.writeInt(serialized.length);
  50             out.write(serialized);
  51         }
  52
  53         @Override
  54         public void readExternal(final ObjectInput in) throws IOException, ClassNotFoundException {
  55             final int length = in.readInt();
  56             serialized = new byte[length];
  57             in.readFully(serialized);
  58         }
  59
  60         private Object readResolve() {
  61             return new CommitTransactionPayload(serialized);
  62         }
  63     }
  64
  65     private static final long serialVersionUID = 1L;
  66
  67     private final byte[] serialized;
  68
  69     CommitTransactionPayload(final byte[] serialized) {
  70         this.serialized = Preconditions.checkNotNull(serialized);
  71     }
  72
  73     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  74             final DataTreeCandidate candidate) throws IOException {
  75         final ByteArrayDataOutput out = ByteStreams.newDataOutput();
  76         transactionId.writeTo(out);
  77         DataTreeCandidateInputOutput.writeDataTreeCandidate(out, candidate);
  78         return new CommitTransactionPayload(out.toByteArray());
  79     }
  80
  81     @Override
  82     public Entry<Optional<TransactionIdentifier>, DataTreeCandidate> getCandidate() throws IOException {
  83         final DataInput in = ByteStreams.newDataInput(serialized);
  84         return new SimpleImmutableEntry<>(Optional.of(TransactionIdentifier.readFrom(in)),
  85                 DataTreeCandidateInputOutput.readDataTreeCandidate(in));
  86     }
  87
  88     @Override
  89     public int size() {
  90         return serialized.length;
  91     }
  92
  93     private Object writeReplace() {
  94         return new Proxy(serialized);
  95     }
  96 }