| /* |
| * 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.runners.apex.translation.utils; |
| |
| import java.io.IOException; |
| import java.io.Serializable; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.NoSuchElementException; |
| import javax.annotation.Nullable; |
| import org.apache.beam.sdk.coders.Coder; |
| import org.apache.beam.sdk.io.UnboundedSource; |
| import org.apache.beam.sdk.options.PipelineOptions; |
| import org.joda.time.Instant; |
| |
| /** |
| * collection as {@link UnboundedSource}, used for tests. |
| */ |
| public class CollectionSource<T> extends UnboundedSource<T, UnboundedSource.CheckpointMark> { |
| private static final long serialVersionUID = 1L; |
| private final Collection<T> collection; |
| private final Coder<T> coder; |
| |
| public CollectionSource(Collection<T> collection, Coder<T> coder) { |
| this.collection = collection; |
| this.coder = coder; |
| } |
| |
| @Override |
| public List<? extends UnboundedSource<T, CheckpointMark>> split( |
| int desiredNumSplits, PipelineOptions options) throws Exception { |
| return Collections.singletonList(this); |
| } |
| |
| @Override |
| public UnboundedReader<T> createReader(PipelineOptions options, |
| @Nullable UnboundedSource.CheckpointMark checkpointMark) { |
| return new CollectionReader<>(collection, this); |
| } |
| |
| @Nullable |
| @Override |
| public Coder<CheckpointMark> getCheckpointMarkCoder() { |
| return null; |
| } |
| |
| @Override |
| public Coder<T> getOutputCoder() { |
| return coder; |
| } |
| |
| private static class CollectionReader<T> extends UnboundedSource.UnboundedReader<T> |
| implements Serializable { |
| |
| private T current; |
| private final CollectionSource<T> source; |
| private final Collection<T> collection; |
| private Iterator<T> iterator; |
| |
| public CollectionReader(Collection<T> collection, CollectionSource<T> source) { |
| this.collection = collection; |
| this.source = source; |
| } |
| |
| @Override |
| public boolean start() throws IOException { |
| if (null == iterator) { |
| iterator = collection.iterator(); |
| } |
| return advance(); |
| } |
| |
| @Override |
| public boolean advance() throws IOException { |
| if (iterator.hasNext()) { |
| current = iterator.next(); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| @Override |
| public Instant getWatermark() { |
| return Instant.now(); |
| } |
| |
| @Override |
| public UnboundedSource.CheckpointMark getCheckpointMark() { |
| return null; |
| } |
| |
| @Override |
| public UnboundedSource<T, ?> getCurrentSource() { |
| return source; |
| } |
| |
| @Override |
| public T getCurrent() throws NoSuchElementException { |
| return current; |
| } |
| |
| @Override |
| public Instant getCurrentTimestamp() throws NoSuchElementException { |
| return Instant.now(); |
| } |
| |
| @Override |
| public void close() throws IOException { |
| } |
| } |
| } |