Java tutorial
/** * Copyright 2016 Yahoo Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.yahoo.pulsar.client.impl; import static com.google.common.base.Preconditions.checkNotNull; import java.io.IOException; import com.google.common.base.Objects; import com.google.common.collect.ComparisonChain; import com.google.protobuf.UninitializedMessageException; import com.yahoo.pulsar.client.api.MessageId; import com.yahoo.pulsar.common.api.proto.PulsarApi; import com.yahoo.pulsar.common.api.proto.PulsarApi.MessageIdData; import com.yahoo.pulsar.common.util.protobuf.ByteBufCodedInputStream; import com.yahoo.pulsar.common.util.protobuf.ByteBufCodedOutputStream; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; public class MessageIdImpl implements MessageId, Comparable<MessageIdImpl> { protected final long ledgerId; protected final long entryId; protected final int partitionIndex; public MessageIdImpl(long ledgerId, long entryId, int partitionIndex) { this.ledgerId = ledgerId; this.entryId = entryId; this.partitionIndex = partitionIndex; } public long getLedgerId() { return ledgerId; } public long getEntryId() { return entryId; } int getPartitionIndex() { return partitionIndex; } @Override public int compareTo(MessageIdImpl other) { return ComparisonChain.start().compare(this.ledgerId, other.ledgerId).compare(this.entryId, other.entryId) .compare(this.getPartitionIndex(), other.getPartitionIndex()).result(); } @Override public int hashCode() { return (int) (31 * (ledgerId + 31 * entryId) + partitionIndex); } @Override public boolean equals(Object obj) { if (obj instanceof MessageIdImpl) { MessageIdImpl other = (MessageIdImpl) obj; return ledgerId == other.ledgerId && entryId == other.entryId && partitionIndex == other.partitionIndex; } return false; } @Override public String toString() { return Objects.toStringHelper(MessageIdImpl.class).add("ledgerId", ledgerId).add("entryId", entryId) .add("partitionIndex", partitionIndex).toString(); } // / Serialization public static MessageId fromByteArray(byte[] data) throws IOException { checkNotNull(data); ByteBufCodedInputStream inputStream = ByteBufCodedInputStream .get(Unpooled.wrappedBuffer(data, 0, data.length)); PulsarApi.MessageIdData.Builder builder = PulsarApi.MessageIdData.newBuilder(); PulsarApi.MessageIdData idData; try { idData = builder.mergeFrom(inputStream, null).build(); } catch (UninitializedMessageException e) { throw new IOException(e); } MessageIdImpl messageId; if (idData.hasBatchIndex()) { messageId = new BatchMessageIdImpl(idData.getLedgerId(), idData.getEntryId(), idData.getPartition(), idData.getBatchIndex()); } else { messageId = new MessageIdImpl(idData.getLedgerId(), idData.getEntryId(), idData.getPartition()); } inputStream.recycle(); builder.recycle(); idData.recycle(); return messageId; } // batchIndex is -1 if message is non-batched message and has the batchIndex for a batch message protected byte[] toByteArray(int batchIndex) { MessageIdData.Builder builder = MessageIdData.newBuilder(); builder.setLedgerId(ledgerId); builder.setEntryId(entryId); if (partitionIndex >= 0) { builder.setPartition(partitionIndex); } if (batchIndex != -1) { builder.setBatchIndex(batchIndex); } MessageIdData msgId = builder.build(); int size = msgId.getSerializedSize(); ByteBuf serialized = Unpooled.buffer(size, size); ByteBufCodedOutputStream stream = ByteBufCodedOutputStream.get(serialized); try { msgId.writeTo(stream); } catch (IOException e) { // This is in-memory serialization, should not fail throw new RuntimeException(e); } msgId.recycle(); builder.recycle(); stream.recycle(); return serialized.array(); } @Override public byte[] toByteArray() { // there is no message batch so we pass -1 return toByteArray(-1); } }