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 static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.annotations.Beta;
  13 import com.google.common.annotations.VisibleForTesting;
  14 import com.google.common.io.ByteArrayDataOutput;
  15 import com.google.common.io.ByteStreams;
  16 import java.io.DataInput;
  17 import java.io.Externalizable;
  18 import java.io.IOException;
  19 import java.io.ObjectInput;
  20 import java.io.ObjectOutput;
  21 import java.io.Serializable;
  22 import java.util.AbstractMap.SimpleImmutableEntry;
  23 import java.util.Map.Entry;
  24 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  25 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  26 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  27 import org.opendaylight.yangtools.yang.data.impl.schema.ReusableImmutableNormalizedNodeStreamWriter;
  28 import org.slf4j.Logger;
  29 import org.slf4j.LoggerFactory;
  30
  31 /**
  32  * Payload persisted when a transaction commits. It contains the transaction identifier and the
  33  * {@link DataTreeCandidate}
  34  *
  35  * @author Robert Varga
  36  */
  37 @Beta
  38 public final class CommitTransactionPayload extends Payload implements Serializable {
  39     private static final Logger LOG = LoggerFactory.getLogger(CommitTransactionPayload.class);
  40
  41     private static final class Proxy implements Externalizable {
  42         private static final long serialVersionUID = 1L;
  43         private byte[] serialized;
  44
  45         // checkstyle flags the public modifier as redundant which really doesn't make sense since it clearly isn't
  46         // redundant. It is explicitly needed for Java serialization to be able to create instances via reflection.
  47         @SuppressWarnings("checkstyle:RedundantModifier")
  48         public Proxy() {
  49             // For Externalizable
  50         }
  51
  52         Proxy(final byte[] serialized) {
  53             this.serialized = requireNonNull(serialized);
  54         }
  55
  56         @Override
  57         public void writeExternal(final ObjectOutput out) throws IOException {
  58             out.writeInt(serialized.length);
  59             out.write(serialized);
  60         }
  61
  62         @Override
  63         public void readExternal(final ObjectInput in) throws IOException {
  64             final int length = in.readInt();
  65             serialized = new byte[length];
  66             in.readFully(serialized);
  67         }
  68
  69         private Object readResolve() {
  70             return new CommitTransactionPayload(serialized);
  71         }
  72     }
  73
  74     private static final long serialVersionUID = 1L;
  75
  76     private final byte[] serialized;
  77
  78     CommitTransactionPayload(final byte[] serialized) {
  79         this.serialized = requireNonNull(serialized);
  80     }
  81
  82     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  83             final DataTreeCandidate candidate, final int initialSerializedBufferCapacity) throws IOException {
  84         final ByteArrayDataOutput out = ByteStreams.newDataOutput(initialSerializedBufferCapacity);
  85         transactionId.writeTo(out);
  86         DataTreeCandidateInputOutput.writeDataTreeCandidate(out, candidate);
  87         final byte[] serialized = out.toByteArray();
  88
  89         LOG.debug("Initial buffer capacity {}, actual serialized size {}",
  90                 initialSerializedBufferCapacity, serialized.length);
  91
  92         return new CommitTransactionPayload(serialized);
  93     }
  94
  95     @VisibleForTesting
  96     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  97             final DataTreeCandidate candidate) throws IOException {
  98         return create(transactionId, candidate, 512);
  99     }
 100
 101     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate() throws IOException {
 102         return getCandidate(ReusableImmutableNormalizedNodeStreamWriter.create());
 103     }
 104
 105     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate(
 106             final ReusableImmutableNormalizedNodeStreamWriter writer) throws IOException {
 107         final DataInput in = ByteStreams.newDataInput(serialized);
 108         return new SimpleImmutableEntry<>(TransactionIdentifier.readFrom(in),
 109                 DataTreeCandidateInputOutput.readDataTreeCandidate(in, writer));
 110     }
 111
 112     @Override
 113     public int size() {
 114         return serialized.length;
 115     }
 116
 117     private Object writeReplace() {
 118         return new Proxy(serialized);
 119     }
 120 }