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.runtime;
  
  import org.apache.beam.runners.core.DoFnRunner;
  import org.apache.beam.runners.core.KeyedWorkItem;
  import org.apache.beam.sdk.state.TimeDomain;
  import org.apache.beam.sdk.transforms.DoFn;
  import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
  import org.apache.beam.sdk.values.KV;
  import org.apache.beam.sdk.values.WindowedValue;
  import org.joda.time.Instant;
  
  /** This class wraps a DoFnRunner with keyed StateInternals and TimerInternals access. */
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class DoFnRunnerWithKeyedInternals<InputT, OutputT> implements DoFnRunner<InputT, OutputT> {
    private final DoFnRunner<InputT, OutputT> underlying;
    private final KeyedInternals keyedInternals;
  
    DoFnRunnerWithKeyedInternals(
        DoFnRunner<InputT, OutputT> doFnRunner, KeyedInternals keyedInternals) {
      this.underlying = doFnRunner;
      this.keyedInternals = keyedInternals;
    }
  
    @Override
    public void startBundle() {
      underlying.startBundle();
    }
  
    @Override
    public void processElement(WindowedValue<InputT> elem) {
      // NOTE: this is thread-safe if we only allow concurrency on the per-key basis.
      setKeyedInternals(elem.getValue());
  
      try {
        underlying.processElement(elem);
      } finally {
        clearKeyedInternals();
      }
    }
  
    @Override
    public <KeyT> void onTimer(
        String timerId,
        String timerFamilyId,
        KeyT key,
        BoundedWindow window,
        Instant timestamp,
        Instant outputTimestamp,
        TimeDomain timeDomain) {
      // Note: wrap with KV.of(key, null) as a special use case of setKeyedInternals() to set key
      // directly.
      setKeyedInternals(KV.of(key, null));
  
      try {
        underlying.onTimer(
            timerId, timerFamilyId, key, window, timestamp, outputTimestamp, timeDomain);
      } finally {
        clearKeyedInternals();
      }
    }
  
    @Override
    public void finishBundle() {
      underlying.finishBundle();
    }
  
    @Override
    public <KeyT> void onWindowExpiration(BoundedWindow window, Instant timestamp, KeyT key) {
      underlying.onWindowExpiration(window, timestamp, key);
    }
  
    @Override
    public DoFn<InputT, OutputT> getFn() {
      return underlying.getFn();
    }
  
    private void setKeyedInternals(Object value) {
      if (value instanceof KeyedWorkItem) {
        keyedInternals.setKey(((KeyedWorkItem<?, ?>) value).key());
      } else if (value instanceof KeyedTimerData) {
        final Object key = ((KeyedTimerData) value).getKey();
        if (key != null) {
          keyedInternals.setKey(key);
        }
      } else if (value instanceof KV) {
        keyedInternals.setKey(((KV<?, ?>) value).getKey());
      } else {
        throw new UnsupportedOperationException(
            String.format(
                "%s is not supported in %s", value.getClass(), DoFnRunnerWithKeyedInternals.class));
      }
    }
  
    private void clearKeyedInternals() {
      keyedInternals.clearKey();
    }
  }
  