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.annotations.VisibleForTesting;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.io.ByteArrayDataOutput;
  14 import com.google.common.io.ByteStreams;
  15 import java.io.DataInput;
  16 import java.io.Externalizable;
  17 import java.io.IOException;
  18 import java.io.ObjectInput;
  19 import java.io.ObjectOutput;
  20 import java.io.Serializable;
  21 import java.util.AbstractMap.SimpleImmutableEntry;
  22 import java.util.Map.Entry;
  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 import org.opendaylight.yangtools.yang.data.impl.schema.ReusableImmutableNormalizedNodeStreamWriter;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 /**
  31  * Payload persisted when a transaction commits. It contains the transaction identifier and the
  32  * {@link DataTreeCandidate}
  33  *
  34  * @author Robert Varga
  35  */
  36 @Beta
  37 public final class CommitTransactionPayload extends Payload implements Serializable {
  38     private static final Logger LOG = LoggerFactory.getLogger(CommitTransactionPayload.class);
  39
  40     private static final class Proxy implements Externalizable {
  41         private static final long serialVersionUID = 1L;
  42         private byte[] serialized;
  43
  44         // checkstyle flags the public modifier as redundant which really doesn't make sense since it clearly isn't
  45         // redundant. It is explicitly needed for Java serialization to be able to create instances via reflection.
  46         @SuppressWarnings("checkstyle:RedundantModifier")
  47         public Proxy() {
  48             // For Externalizable
  49         }
  50
  51         Proxy(final byte[] serialized) {
  52             this.serialized = Preconditions.checkNotNull(serialized);
  53         }
  54
  55         @Override
  56         public void writeExternal(final ObjectOutput out) throws IOException {
  57             out.writeInt(serialized.length);
  58             out.write(serialized);
  59         }
  60
  61         @Override
  62         public void readExternal(final ObjectInput in) throws IOException {
  63             final int length = in.readInt();
  64             serialized = new byte[length];
  65             in.readFully(serialized);
  66         }
  67
  68         private Object readResolve() {
  69             return new CommitTransactionPayload(serialized);
  70         }
  71     }
  72
  73     private static final long serialVersionUID = 1L;
  74
  75     private final byte[] serialized;
  76
  77     CommitTransactionPayload(final byte[] serialized) {
  78         this.serialized = Preconditions.checkNotNull(serialized);
  79     }
  80
  81     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  82             final DataTreeCandidate candidate, final int initialSerializedBufferCapacity) throws IOException {
  83         final ByteArrayDataOutput out = ByteStreams.newDataOutput(initialSerializedBufferCapacity);
  84         transactionId.writeTo(out);
  85         DataTreeCandidateInputOutput.writeDataTreeCandidate(out, candidate);
  86         final byte[] serialized = out.toByteArray();
  87
  88         LOG.debug("Initial buffer capacity {}, actual serialized size {}",
  89                 initialSerializedBufferCapacity, serialized.length);
  90
  91         return new CommitTransactionPayload(serialized);
  92     }
  93
  94     @VisibleForTesting
  95     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  96             final DataTreeCandidate candidate) throws IOException {
  97         return create(transactionId, candidate, 512);
  98     }
  99
 100     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate() throws IOException {
 101         return getCandidate(ReusableImmutableNormalizedNodeStreamWriter.create());
 102     }
 103
 104     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate(
 105             final ReusableImmutableNormalizedNodeStreamWriter writer) throws IOException {
 106         final DataInput in = ByteStreams.newDataInput(serialized);
 107         return new SimpleImmutableEntry<>(TransactionIdentifier.readFrom(in),
 108                 DataTreeCandidateInputOutput.readDataTreeCandidate(in, writer));
 109     }
 110
 111     @Override
 112     public int size() {
 113         return serialized.length;
 114     }
 115
 116     private Object writeReplace() {
 117         return new Proxy(serialized);
 118     }
 119 }