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.function.SupplierEx;
  import com.hazelcast.jet.core.AbstractProcessor;
  import com.hazelcast.jet.core.Edge;
  import com.hazelcast.jet.core.Processor;
  import java.util.HashMap;
  import java.util.Map;
  import javax.annotation.Nonnull;
  import org.apache.beam.runners.jet.DAGBuilder;
  import org.apache.beam.runners.jet.Utils;
  import org.apache.beam.sdk.coders.Coder;
  import org.apache.beam.sdk.values.WindowedValue;
  
  /** Jet {@link com.hazelcast.jet.core.Processor} implementation for Beam's Flatten primitive. */
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class FlattenP extends AbstractProcessor {
  
    private final Map<Integer, Coder> inputOrdinalCoders;
    private final Coder outputCoder;
  
    @SuppressWarnings({"FieldCanBeLocal", "unused"}) // do not remove, useful for debugging
    private final String ownerId;
  
    private FlattenP(Map<Integer, Coder> inputOrdinalCoders, Coder outputCoder, String ownerId) {
      this.inputOrdinalCoders = inputOrdinalCoders;
      this.outputCoder = outputCoder;
      this.ownerId = ownerId;
    }
  
    @Override
    protected boolean tryProcess(int ordinal, @Nonnull Object item) {
      Coder inputCoder = inputOrdinalCoders.get(ordinal);
      WindowedValue<Object> windowedValue = Utils.decodeWindowedValue((byte[]) item, inputCoder);
      return tryEmit(Utils.encode(windowedValue, outputCoder));
    }
  
    /** Jet {@link Processor} supplier that will provide instances of {@link FlattenP}. */
    public static final class Supplier implements SupplierEx<Processor>, DAGBuilder.WiringListener {
  
      private final Map<String, Coder> inputCollectionCoders;
      private final Coder outputCoder;
      private final String ownerId;
      private final Map<Integer, Coder> inputOrdinalCoders;
  
      public Supplier(Map<String, Coder> inputCoders, Coder outputCoder, String ownerId) {
        this.inputCollectionCoders = inputCoders;
        this.outputCoder = outputCoder;
        this.ownerId = ownerId;
        this.inputOrdinalCoders = new HashMap<>();
      }
  
      @Override
      public Processor getEx() {
        return new FlattenP(inputOrdinalCoders, outputCoder, ownerId);
      }
  
      @Override
      public void isOutboundEdgeOfVertex(Edge edge, String edgeId, String pCollId, String vertexId) {
        // do nothing
      }
  
      @Override
      public void isInboundEdgeOfVertex(Edge edge, String edgeId, String pCollId, String vertexId) {
        if (ownerId.equals(vertexId)) {
          Coder coder = inputCollectionCoders.get(edgeId);
          inputOrdinalCoders.put(edge.getDestOrdinal(), coder);
        }
      }
    }
  }
  