| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.beam.sdk.io.kinesis; |
| |
| import static org.apache.beam.vendor.guava.v20_0.com.google.common.collect.Lists.newArrayList; |
| import static org.apache.beam.vendor.guava.v20_0.com.google.common.collect.Lists.partition; |
| |
| import java.io.IOException; |
| import java.io.Serializable; |
| import java.util.Iterator; |
| import java.util.List; |
| import org.apache.beam.sdk.io.UnboundedSource; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.ImmutableList; |
| |
| /** |
| * Checkpoint representing a total progress in a set of shards in single stream. The set of shards |
| * covered by {@link KinesisReaderCheckpoint} may or may not be equal to set of all shards present |
| * in the stream. This class is immutable. |
| */ |
| class KinesisReaderCheckpoint |
| implements Iterable<ShardCheckpoint>, UnboundedSource.CheckpointMark, Serializable { |
| |
| private final List<ShardCheckpoint> shardCheckpoints; |
| |
| public KinesisReaderCheckpoint(Iterable<ShardCheckpoint> shardCheckpoints) { |
| this.shardCheckpoints = ImmutableList.copyOf(shardCheckpoints); |
| } |
| |
| /** |
| * Splits given multi-shard checkpoint into partitions of approximately equal size. |
| * |
| * @param desiredNumSplits - upper limit for number of partitions to generate. |
| * @return list of checkpoints covering consecutive partitions of current checkpoint. |
| */ |
| public List<KinesisReaderCheckpoint> splitInto(int desiredNumSplits) { |
| int partitionSize = divideAndRoundUp(shardCheckpoints.size(), desiredNumSplits); |
| |
| List<KinesisReaderCheckpoint> checkpoints = newArrayList(); |
| for (List<ShardCheckpoint> shardPartition : partition(shardCheckpoints, partitionSize)) { |
| checkpoints.add(new KinesisReaderCheckpoint(shardPartition)); |
| } |
| return checkpoints; |
| } |
| |
| private int divideAndRoundUp(int nominator, int denominator) { |
| return (nominator + denominator - 1) / denominator; |
| } |
| |
| @Override |
| public void finalizeCheckpoint() throws IOException {} |
| |
| @Override |
| public String toString() { |
| return shardCheckpoints.toString(); |
| } |
| |
| @Override |
| public Iterator<ShardCheckpoint> iterator() { |
| return shardCheckpoints.iterator(); |
| } |
| } |