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.samza.transforms;
  
  import org.apache.beam.sdk.transforms.PTransform;
  import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.PInput;
  import org.apache.beam.sdk.values.POutput;
  
  /**
   * A wrapper transform of {@link org.apache.beam.sdk.transforms.GroupByKey} or {@link
   * org.apache.beam.sdk.transforms.join.CoGroupByKey} to indicate there is no repartition needed for
   * Samza runner. For example:
   *
   * <p>input.apply(GroupWithoutRepartition.of(Count.perKey()));
   */
  public class GroupWithoutRepartition<InputT extends PInput, OutputT extends POutput>
      extends PTransform<InputT, OutputT> {
    private final PTransform<InputT, OutputT> transform;
  
    public static <InputT extends PInput, OutputT extends POutput>
        GroupWithoutRepartition<InputT, OutputT> of(PTransform<InputT, OutputT> transform) {
      return new GroupWithoutRepartition<>(transform);
    }
  
    private GroupWithoutRepartition(PTransform<InputT, OutputT> transform) {
      this.transform = transform;
    }
  
    @Override
    @SuppressWarnings("unchecked")
    public OutputT expand(InputT input) {
      if (input instanceof PCollection) {
        return (OutputT) ((PCollection) input).apply(transform);
      } else if (input instanceof KeyedPCollectionTuple) {
        return (OutputT) ((KeyedPCollectionTuple) input).apply(transform);
      } else {
        throw new RuntimeException(
            transform.getName()
                + " is not supported with "
                + GroupWithoutRepartition.class.getSimpleName());
      }
    }
  }
  