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.stream.ReusableStreamReceiver;
  27 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  28 import org.opendaylight.yangtools.yang.data.impl.schema.ReusableImmutableNormalizedNodeStreamWriter;
  29 import org.slf4j.Logger;
  30 import org.slf4j.LoggerFactory;
  31
  32 /**
  33  * Payload persisted when a transaction commits. It contains the transaction identifier and the
  34  * {@link DataTreeCandidate}
  35  *
  36  * @author Robert Varga
  37  */
  38 @Beta
  39 public final class CommitTransactionPayload extends Payload implements Serializable {
  40     private static final Logger LOG = LoggerFactory.getLogger(CommitTransactionPayload.class);
  41
  42     private static final class Proxy implements Externalizable {
  43         private static final long serialVersionUID = 1L;
  44         private byte[] serialized;
  45
  46         // checkstyle flags the public modifier as redundant which really doesn't make sense since it clearly isn't
  47         // redundant. It is explicitly needed for Java serialization to be able to create instances via reflection.
  48         @SuppressWarnings("checkstyle:RedundantModifier")
  49         public Proxy() {
  50             // For Externalizable
  51         }
  52
  53         Proxy(final byte[] serialized) {
  54             this.serialized = requireNonNull(serialized);
  55         }
  56
  57         @Override
  58         public void writeExternal(final ObjectOutput out) throws IOException {
  59             out.writeInt(serialized.length);
  60             out.write(serialized);
  61         }
  62
  63         @Override
  64         public void readExternal(final ObjectInput in) throws IOException {
  65             final int length = in.readInt();
  66             serialized = new byte[length];
  67             in.readFully(serialized);
  68         }
  69
  70         private Object readResolve() {
  71             return new CommitTransactionPayload(serialized);
  72         }
  73     }
  74
  75     private static final long serialVersionUID = 1L;
  76
  77     private final byte[] serialized;
  78
  79     CommitTransactionPayload(final byte[] serialized) {
  80         this.serialized = requireNonNull(serialized);
  81     }
  82
  83     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  84             final DataTreeCandidate candidate, final int initialSerializedBufferCapacity) throws IOException {
  85         final ByteArrayDataOutput out = ByteStreams.newDataOutput(initialSerializedBufferCapacity);
  86         transactionId.writeTo(out);
  87         DataTreeCandidateInputOutput.writeDataTreeCandidate(out, candidate);
  88         final byte[] serialized = out.toByteArray();
  89
  90         LOG.debug("Initial buffer capacity {}, actual serialized size {}",
  91                 initialSerializedBufferCapacity, serialized.length);
  92
  93         return new CommitTransactionPayload(serialized);
  94     }
  95
  96     @VisibleForTesting
  97     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  98             final DataTreeCandidate candidate) throws IOException {
  99         return create(transactionId, candidate, 512);
 100     }
 101
 102     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate() throws IOException {
 103         return getCandidate(ReusableImmutableNormalizedNodeStreamWriter.create());
 104     }
 105
 106     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate(final ReusableStreamReceiver receiver)
 107             throws IOException {
 108         final DataInput in = ByteStreams.newDataInput(serialized);
 109         return new SimpleImmutableEntry<>(TransactionIdentifier.readFrom(in),
 110                 DataTreeCandidateInputOutput.readDataTreeCandidate(in, receiver));
 111     }
 112
 113     @Override
 114     public int size() {
 115         return serialized.length;
 116     }
 117
 118     private Object writeReplace() {
 119         return new Proxy(serialized);
 120     }
 121 }