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.sdk.util.construction;
  
  import com.google.auto.service.AutoService;
  import java.util.Collections;
  import java.util.Map;
  import org.apache.beam.model.pipeline.v1.RunnerApi;
  import org.apache.beam.model.pipeline.v1.RunnerApi.FunctionSpec;
  import org.apache.beam.sdk.runners.AppliedPTransform;
  import org.apache.beam.sdk.transforms.GroupByKey;
  import org.apache.beam.sdk.transforms.PTransform;
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  /**
   * Utility methods for translating a {@link GroupByKey} to and from {@link RunnerApi}
   * representations.
   */
  @SuppressWarnings({
    "nullness", // TODO(https://github.com/apache/beam/issues/20497)
    "rawtypes" // TODO(https://github.com/apache/beam/issues/20447)
  })
  public class GroupByKeyTranslation {
  
    static class GroupByKeyTranslator
        implements PTransformTranslation.TransformPayloadTranslator<GroupByKey<?, ?>> {
      @Override
      public String getUrn() {
        return PTransformTranslation.GROUP_BY_KEY_TRANSFORM_URN;
      }
  
      @Override
      public String getUrn(GroupByKey<?, ?> transform) {
        if (transform.surroundsGBEK()) {
          return PTransformTranslation.GROUP_BY_KEY_WRAPPER_TRANSFORM_URN;
        }
        return PTransformTranslation.GROUP_BY_KEY_TRANSFORM_URN;
      }
  
      @Override
      @Nullable
      public FunctionSpec translate(
          AppliedPTransform<?, ?, GroupByKey<?, ?>> transform, SdkComponents components) {
        if (transform.getTransform().surroundsGBEK()) {
          // Can use null for spec for empty composite.
          return null;
        }
        return FunctionSpec.newBuilder().setUrn(getUrn(transform.getTransform())).build();
      }
    }
  
    /** Registers {@link GroupByKeyTranslator}. */
    @AutoService(TransformPayloadTranslatorRegistrar.class)
    public static class Registrar implements TransformPayloadTranslatorRegistrar {
      @Override
      public Map<
              ? extends Class<? extends PTransform>,
              ? extends PTransformTranslation.TransformPayloadTranslator>
          getTransformPayloadTranslators() {
        return Collections.singletonMap(GroupByKey.class, new GroupByKeyTranslator());
      }
    }
  }
  