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.
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  package org.apache.beam.runners.dataflow;
  
  import java.util.Map;
  import org.apache.beam.sdk.runners.AppliedPTransform;
  import org.apache.beam.sdk.runners.PTransformOverrideFactory;
  import org.apache.beam.sdk.transforms.PTransform;
  import org.apache.beam.sdk.transforms.ParDo;
  import org.apache.beam.sdk.util.construction.ForwardingPTransform;
  import org.apache.beam.sdk.util.construction.PTransformReplacements;
  import org.apache.beam.sdk.util.construction.ReplacementOutputs;
  import org.apache.beam.sdk.util.construction.SplittableParDo;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.PCollectionTuple;
  import org.apache.beam.sdk.values.TupleTag;
  import org.apache.beam.sdk.values.TupleTagList;
  
  /** Transform overrides for supporting {@link SplittableParDo} in the Dataflow runner. */
  class SplittableParDoOverrides {
    static class ParDoSingleViaMulti<InputT, OutputT>
        extends ForwardingPTransform<PCollection<? extends InputT>, PCollection<OutputT>> {
      private final ParDo.SingleOutput<InputT, OutputT> original;
  
      public ParDoSingleViaMulti(
          DataflowRunner ignored, ParDo.SingleOutput<InputT, OutputT> original) {
        this.original = original;
      }
  
      @Override
      protected PTransform<PCollection<? extends InputT>, PCollection<OutputT>> delegate() {
        return original;
      }
  
      @Override
      public PCollection<OutputT> expand(PCollection<? extends InputT> input) {
        TupleTag<OutputT> mainOutput = new TupleTag<>();
        return input.apply(original.withOutputTags(mainOutput, TupleTagList.empty())).get(mainOutput);
      }
    }
  
    static class SplittableParDoOverrideFactory<InputT, OutputT, RestrictionT>
        implements PTransformOverrideFactory<
            PCollection<InputT>, PCollectionTuple, ParDo.MultiOutput<InputT, OutputT>> {
      @Override
      public PTransformReplacement<PCollection<InputT>, PCollectionTuple> getReplacementTransform(
          AppliedPTransform<PCollection<InputT>, PCollectionTuple, ParDo.MultiOutput<InputT, OutputT>>
              appliedTransform) {
        return PTransformReplacement.of(
            PTransformReplacements.getSingletonMainInput(appliedTransform),
            SplittableParDo.forAppliedParDo(appliedTransform));
      }
  
      @Override
      public Map<PCollection<?>, ReplacementOutput> mapOutputs(
          Map<TupleTag<?>, PCollection<?>> outputs, PCollectionTuple newOutput) {
        return ReplacementOutputs.tagged(outputs, newOutput);
      }
    }
  }
  