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.jet.processors;
  
  import com.hazelcast.cluster.Address;
  import com.hazelcast.jet.core.AbstractProcessor;
  import com.hazelcast.jet.core.Processor;
  import com.hazelcast.jet.core.ProcessorMetaSupplier;
  import com.hazelcast.jet.core.ProcessorSupplier;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  import java.util.function.Function;
  import javax.annotation.Nonnull;
  import org.apache.beam.runners.jet.Utils;
  import org.apache.beam.sdk.coders.Coder;
  import org.apache.beam.sdk.values.WindowedValues;
  
  /**
   * /** * Jet {@link com.hazelcast.jet.core.Processor} implementation for Beam's Impulse primitive.
   */
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class ImpulseP extends AbstractProcessor {
  
    private final boolean active;
    private final Coder outputCoder;
  
    @SuppressWarnings("unused")
    private final String ownerId; // do not remove it, very useful for debugging
  
    private ImpulseP(boolean active, Coder outputCoder, String ownerId) {
      this.active = active;
      this.outputCoder = outputCoder;
      this.ownerId = ownerId;
    }
  
    @Override
    public boolean complete() {
      if (active) {
        return tryEmit(Utils.encode(WindowedValues.valueInGlobalWindow(new byte[0]), outputCoder));
      } else {
        return true;
      }
    }
  
    public static ProcessorMetaSupplier supplier(Coder outputCoder, String ownerId) {
      return new ImpulseMetaProcessorSupplier(outputCoder, ownerId);
    }
  
    private static class ImpulseMetaProcessorSupplier implements ProcessorMetaSupplier {
  
      private final Coder outputCoder;
      private final String ownerId;
  
      private ImpulseMetaProcessorSupplier(Coder outputCoder, String ownerId) {
        this.outputCoder = outputCoder;
        this.ownerId = ownerId;
      }
  
      @SuppressWarnings("unchecked")
      @Nonnull
      @Override
      public Function<? super Address, ? extends ProcessorSupplier> get(
          @Nonnull List<Address> addresses) {
        return address -> new ImpulseProcessorSupplier(outputCoder, ownerId);
      }
    }
  
    private static class ImpulseProcessorSupplier<T> implements ProcessorSupplier {
      private final Coder outputCoder;
      private final String ownerId;
      private transient ProcessorSupplier.Context context;
  
      private ImpulseProcessorSupplier(Coder outputCoder, String ownerId) {
        this.outputCoder = outputCoder;
        this.ownerId = ownerId;
      }
  
      @Override
      public void init(@Nonnull Context context) {
        this.context = context;
      }
  
      @Nonnull
      @Override
      public Collection<? extends Processor> get(int count) {
        int indexBase = context.memberIndex() * context.localParallelism();
        List<Processor> res = new ArrayList<>(count);
        for (int i = 0; i < count; i++, indexBase++) {
          res.add(new ImpulseP(indexBase == 0, outputCoder, ownerId));
        }
        return res;
      }
    }
  }
  