content: /*
   * 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.flink.translation.wrappers.streaming.io.source.bounded;
  
  import javax.annotation.Nullable;
  import org.apache.beam.runners.core.construction.SerializablePipelineOptions;
  import org.apache.beam.runners.flink.translation.wrappers.streaming.io.source.FlinkSource;
  import org.apache.beam.runners.flink.translation.wrappers.streaming.io.source.FlinkSourceSplit;
  import org.apache.beam.sdk.io.BoundedSource;
  import org.apache.beam.sdk.values.WindowedValue;
  import org.apache.flink.api.connector.source.Boundedness;
  import org.apache.flink.api.connector.source.SourceReader;
  import org.apache.flink.api.connector.source.SourceReaderContext;
  
  /**
   * A Flink {@link org.apache.flink.api.connector.source.Source Source} implementation that wraps a
   * Beam {@link BoundedSource BoundedSource}.
   *
   * <p>A {@link FlinkBoundedSource} can run in either batch or streaming mode, depending on its
   * {@link Boundedness} setting. For a BoundedSource running in streaming mode, it is acting like a
   * "finite stream".
   *
   * @param <T> The output type of the wrapped Beam {@link BoundedSource BoundedSource}.
   */
  public class FlinkBoundedSource<T> extends FlinkSource<T, WindowedValue<T>> {
    protected final @Nullable TimestampExtractor<WindowedValue<T>> timestampExtractor;
  
    public FlinkBoundedSource(
        String stepName,
        BoundedSource<T> beamSource,
        SerializablePipelineOptions serializablePipelineOptions,
        Boundedness boundedness,
        int numSplits) {
      this(stepName, beamSource, serializablePipelineOptions, boundedness, numSplits, null);
    }
  
    public FlinkBoundedSource(
        String stepName,
        BoundedSource<T> beamSource,
        SerializablePipelineOptions serializablePipelineOptions,
        Boundedness boundedness,
        int numSplits,
        @Nullable TimestampExtractor<WindowedValue<T>> timestampExtractor) {
  
      super(stepName, beamSource, serializablePipelineOptions, boundedness, numSplits);
      this.timestampExtractor = timestampExtractor;
    }
  
    @Override
    public SourceReader<WindowedValue<T>, FlinkSourceSplit<T>> createReader(
        SourceReaderContext readerContext) throws Exception {
      return new FlinkBoundedSourceReader<>(
          stepName, readerContext, serializablePipelineOptions.get(), timestampExtractor);
    }
  }
  