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 com.google.common.base.Verify.verifyNotNull;
  11 import static java.util.Objects.requireNonNull;
  12 import static org.opendaylight.controller.cluster.datastore.persisted.ChunkedOutputStream.MAX_ARRAY_SIZE;
  13
  14 import com.google.common.annotations.Beta;
  15 import com.google.common.annotations.VisibleForTesting;
  16 import com.google.common.io.ByteStreams;
  17 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  18 import java.io.DataInput;
  19 import java.io.DataInputStream;
  20 import java.io.DataOutputStream;
  21 import java.io.Externalizable;
  22 import java.io.IOException;
  23 import java.io.ObjectInput;
  24 import java.io.ObjectOutput;
  25 import java.io.Serializable;
  26 import java.io.StreamCorruptedException;
  27 import java.util.AbstractMap.SimpleImmutableEntry;
  28 import java.util.Map.Entry;
  29 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  30 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  31 import org.opendaylight.yangtools.concepts.Variant;
  32 import org.opendaylight.yangtools.yang.data.api.schema.stream.ReusableStreamReceiver;
  33 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  34 import org.opendaylight.yangtools.yang.data.impl.schema.ReusableImmutableNormalizedNodeStreamWriter;
  35 import org.slf4j.Logger;
  36 import org.slf4j.LoggerFactory;
  37
  38 /**
  39  * Payload persisted when a transaction commits. It contains the transaction identifier and the
  40  * {@link DataTreeCandidate}
  41  *
  42  * @author Robert Varga
  43  */
  44 @Beta
  45 public abstract class CommitTransactionPayload extends Payload implements Serializable {
  46     private static final Logger LOG = LoggerFactory.getLogger(CommitTransactionPayload.class);
  47     private static final long serialVersionUID = 1L;
  48
  49     CommitTransactionPayload() {
  50
  51     }
  52
  53     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  54             final DataTreeCandidate candidate, final int initialSerializedBufferCapacity) throws IOException {
  55
  56         final ChunkedOutputStream cos = new ChunkedOutputStream(initialSerializedBufferCapacity);
  57         try (DataOutputStream dos = new DataOutputStream(cos)) {
  58             transactionId.writeTo(dos);
  59             DataTreeCandidateInputOutput.writeDataTreeCandidate(dos, candidate);
  60         }
  61
  62         final Variant<byte[], ChunkedByteArray> source = cos.toVariant();
  63         LOG.debug("Initial buffer capacity {}, actual serialized size {}", initialSerializedBufferCapacity, cos.size());
  64         return source.isFirst() ? new Simple(source.getFirst()) : new Chunked(source.getSecond());
  65     }
  66
  67     @VisibleForTesting
  68     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  69             final DataTreeCandidate candidate) throws IOException {
  70         return create(transactionId, candidate, 512);
  71     }
  72
  73     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate() throws IOException {
  74         return getCandidate(ReusableImmutableNormalizedNodeStreamWriter.create());
  75     }
  76
  77     public final Entry<TransactionIdentifier, DataTreeCandidate> getCandidate(
  78             final ReusableStreamReceiver receiver) throws IOException {
  79         final DataInput in = newDataInput();
  80         return new SimpleImmutableEntry<>(TransactionIdentifier.readFrom(in),
  81                 DataTreeCandidateInputOutput.readDataTreeCandidate(in, receiver));
  82     }
  83
  84     abstract void writeBytes(ObjectOutput out) throws IOException;
  85
  86     abstract DataInput newDataInput();
  87
  88     final Object writeReplace() {
  89         return new Proxy(this);
  90     }
  91
  92     private static final class Simple extends CommitTransactionPayload {
  93         private static final long serialVersionUID = 1L;
  94
  95         private final byte[] serialized;
  96
  97         Simple(final byte[] serialized) {
  98             this.serialized = requireNonNull(serialized);
  99         }
 100
 101         @Override
 102         public int size() {
 103             return serialized.length;
 104         }
 105
 106         @Override
 107         DataInput newDataInput() {
 108             return ByteStreams.newDataInput(serialized);
 109         }
 110
 111         @Override
 112         void writeBytes(final ObjectOutput out) throws IOException {
 113             out.write(serialized);
 114         }
 115     }
 116
 117     private static final class Chunked extends CommitTransactionPayload {
 118         private static final long serialVersionUID = 1L;
 119
 120         @SuppressFBWarnings(value = "SE_BAD_FIELD", justification = "Handled via serialization proxy")
 121         private final ChunkedByteArray source;
 122
 123         Chunked(final ChunkedByteArray source) {
 124             this.source = requireNonNull(source);
 125         }
 126
 127         @Override
 128         void writeBytes(final ObjectOutput out) throws IOException {
 129             source.copyTo(out);
 130         }
 131
 132         @Override
 133         public int size() {
 134             return source.size();
 135         }
 136
 137         @Override
 138         DataInput newDataInput() {
 139             return new DataInputStream(source.openStream());
 140         }
 141     }
 142
 143     private static final class Proxy implements Externalizable {
 144         private static final long serialVersionUID = 1L;
 145
 146         private CommitTransactionPayload payload;
 147
 148         // checkstyle flags the public modifier as redundant which really doesn't make sense since it clearly isn't
 149         // redundant. It is explicitly needed for Java serialization to be able to create instances via reflection.
 150         @SuppressWarnings("checkstyle:RedundantModifier")
 151         public Proxy() {
 152             // For Externalizable
 153         }
 154
 155         Proxy(final CommitTransactionPayload payload) {
 156             this.payload = requireNonNull(payload);
 157         }
 158
 159         @Override
 160         public void writeExternal(final ObjectOutput out) throws IOException {
 161             out.writeInt(payload.size());
 162             payload.writeBytes(out);
 163         }
 164
 165         @Override
 166         public void readExternal(final ObjectInput in) throws IOException {
 167             final int length = in.readInt();
 168             if (length < 0) {
 169                 throw new StreamCorruptedException("Invalid payload length " + length);
 170             } else if (length < MAX_ARRAY_SIZE) {
 171                 final byte[] serialized = new byte[length];
 172                 in.readFully(serialized);
 173                 payload = new Simple(serialized);
 174             } else {
 175                 payload = new Chunked(ChunkedByteArray.readFrom(in, length, MAX_ARRAY_SIZE));
 176             }
 177         }
 178
 179         private Object readResolve() {
 180             return verifyNotNull(payload);
 181         }
 182     }
 183 }