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.IdentifiablePayload;
  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 IdentifiablePayload<TransactionIdentifier>
  46         implements Serializable {
  47     private static final Logger LOG = LoggerFactory.getLogger(CommitTransactionPayload.class);
  48     private static final long serialVersionUID = 1L;
  49
  50     private volatile Entry<TransactionIdentifier, DataTreeCandidate> candidate = null;
  51
  52     CommitTransactionPayload() {
  53
  54     }
  55
  56     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  57             final DataTreeCandidate candidate, final int initialSerializedBufferCapacity) throws IOException {
  58
  59         final ChunkedOutputStream cos = new ChunkedOutputStream(initialSerializedBufferCapacity);
  60         try (DataOutputStream dos = new DataOutputStream(cos)) {
  61             transactionId.writeTo(dos);
  62             DataTreeCandidateInputOutput.writeDataTreeCandidate(dos, candidate);
  63         }
  64
  65         final Variant<byte[], ChunkedByteArray> source = cos.toVariant();
  66         LOG.debug("Initial buffer capacity {}, actual serialized size {}", initialSerializedBufferCapacity, cos.size());
  67         return source.isFirst() ? new Simple(source.getFirst()) : new Chunked(source.getSecond());
  68     }
  69
  70     @VisibleForTesting
  71     public static CommitTransactionPayload create(final TransactionIdentifier transactionId,
  72             final DataTreeCandidate candidate) throws IOException {
  73         return create(transactionId, candidate, 512);
  74     }
  75
  76     public Entry<TransactionIdentifier, DataTreeCandidate> getCandidate() throws IOException {
  77         Entry<TransactionIdentifier, DataTreeCandidate> localCandidate = candidate;
  78         if (localCandidate == null) {
  79             synchronized (this) {
  80                 localCandidate = candidate;
  81                 if (localCandidate == null) {
  82                     candidate = localCandidate = getCandidate(ReusableImmutableNormalizedNodeStreamWriter.create());
  83                 }
  84             }
  85         }
  86         return localCandidate;
  87     }
  88
  89     public final Entry<TransactionIdentifier, DataTreeCandidate> getCandidate(
  90             final ReusableStreamReceiver receiver) throws IOException {
  91         final DataInput in = newDataInput();
  92         return new SimpleImmutableEntry<>(TransactionIdentifier.readFrom(in),
  93                 DataTreeCandidateInputOutput.readDataTreeCandidate(in, receiver));
  94     }
  95
  96     public TransactionIdentifier getIdentifier() {
  97         try  {
  98             return getCandidate().getKey();
  99         } catch (IOException e) {
 100             throw new IllegalStateException("Candidate deserialization failed.", e);
 101         }
 102     }
 103
 104     abstract void writeBytes(ObjectOutput out) throws IOException;
 105
 106     abstract DataInput newDataInput();
 107
 108     final Object writeReplace() {
 109         return new Proxy(this);
 110     }
 111
 112     private static final class Simple extends CommitTransactionPayload {
 113         private static final long serialVersionUID = 1L;
 114
 115         private final byte[] serialized;
 116
 117         Simple(final byte[] serialized) {
 118             this.serialized = requireNonNull(serialized);
 119         }
 120
 121         @Override
 122         public int size() {
 123             return serialized.length;
 124         }
 125
 126         @Override
 127         DataInput newDataInput() {
 128             return ByteStreams.newDataInput(serialized);
 129         }
 130
 131         @Override
 132         void writeBytes(final ObjectOutput out) throws IOException {
 133             out.write(serialized);
 134         }
 135     }
 136
 137     private static final class Chunked extends CommitTransactionPayload {
 138         private static final long serialVersionUID = 1L;
 139
 140         @SuppressFBWarnings(value = "SE_BAD_FIELD", justification = "Handled via serialization proxy")
 141         private final ChunkedByteArray source;
 142
 143         Chunked(final ChunkedByteArray source) {
 144             this.source = requireNonNull(source);
 145         }
 146
 147         @Override
 148         void writeBytes(final ObjectOutput out) throws IOException {
 149             source.copyTo(out);
 150         }
 151
 152         @Override
 153         public int size() {
 154             return source.size();
 155         }
 156
 157         @Override
 158         DataInput newDataInput() {
 159             return new DataInputStream(source.openStream());
 160         }
 161     }
 162
 163     private static final class Proxy implements Externalizable {
 164         private static final long serialVersionUID = 1L;
 165
 166         private CommitTransactionPayload payload;
 167
 168         // checkstyle flags the public modifier as redundant which really doesn't make sense since it clearly isn't
 169         // redundant. It is explicitly needed for Java serialization to be able to create instances via reflection.
 170         @SuppressWarnings("checkstyle:RedundantModifier")
 171         public Proxy() {
 172             // For Externalizable
 173         }
 174
 175         Proxy(final CommitTransactionPayload payload) {
 176             this.payload = requireNonNull(payload);
 177         }
 178
 179         @Override
 180         public void writeExternal(final ObjectOutput out) throws IOException {
 181             out.writeInt(payload.size());
 182             payload.writeBytes(out);
 183         }
 184
 185         @Override
 186         public void readExternal(final ObjectInput in) throws IOException {
 187             final int length = in.readInt();
 188             if (length < 0) {
 189                 throw new StreamCorruptedException("Invalid payload length " + length);
 190             } else if (length < MAX_ARRAY_SIZE) {
 191                 final byte[] serialized = new byte[length];
 192                 in.readFully(serialized);
 193                 payload = new Simple(serialized);
 194             } else {
 195                 payload = new Chunked(ChunkedByteArray.readFrom(in, length, MAX_ARRAY_SIZE));
 196             }
 197         }
 198
 199         private Object readResolve() {
 200             return verifyNotNull(payload);
 201         }
 202     }
 203 }