EdgeTriple.java

/*
 * Copyright © 2014 - 2021 Leipzig University (Database Research Group)
 *
 * Licensed 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.gradoop.flink.model.impl.operators.matching.single.simulation.dual.functions;

import org.apache.flink.api.common.functions.FlatMapFunction;
import org.apache.flink.api.java.functions.FunctionAnnotation;
import org.apache.flink.api.java.tuple.Tuple3;
import org.apache.flink.util.Collector;
import org.gradoop.common.model.impl.id.GradoopId;
import org.gradoop.flink.model.impl.operators.matching.single.simulation.dual.tuples.FatVertex;


import org.gradoop.flink.model.impl.operators.matching.single.simulation.dual.tuples.IdPair;

/**
 * Extracts all edges contained ina a {@link FatVertex}.
 * <p>
 * {@code fatVertex -> [(edgeId,sourceId,targetId)]*}
 */
@FunctionAnnotation.ReadFields("f4")
public class EdgeTriple implements
  FlatMapFunction<FatVertex, Tuple3<GradoopId, GradoopId, GradoopId>> {

  /**
   * Reduce instantiations
   */
  private final Tuple3<GradoopId, GradoopId, GradoopId> reuseTuple;

  /**
   * Constructor
   */
  public EdgeTriple() {
    reuseTuple = new Tuple3<>();
  }

  @Override
  public void flatMap(FatVertex fatVertex,
    Collector<Tuple3<GradoopId, GradoopId, GradoopId>> collector) throws
    Exception {
    reuseTuple.f1 = fatVertex.getVertexId();
    for (IdPair idPair : fatVertex.getEdgeCandidates().keySet()) {
      reuseTuple.f0 = idPair.f0;
      reuseTuple.f2 = idPair.f1;
      collector.collect(reuseTuple);
    }
  }
}