GraphHeadGroup.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.distinction.functions;
import org.apache.flink.api.common.functions.JoinFunction;
import org.apache.flink.api.java.functions.FunctionAnnotation;
import org.apache.flink.api.java.tuple.Tuple2;
import org.gradoop.common.model.api.entities.GraphHead;
import org.gradoop.flink.model.impl.operators.tostring.tuples.GraphHeadString;
/**
* {@code (label, graphId) |><| graphHead => (label, graphHead)}
*
* @param <G> graph head type
*/
@FunctionAnnotation.ForwardedFieldsFirst("f1->f0")
public class GraphHeadGroup<G extends GraphHead>
implements JoinFunction<GraphHeadString, G, Tuple2<String, G>> {
@Override
public Tuple2<String, G> join(GraphHeadString graphHeadString, G graphHead) throws Exception {
return new Tuple2<>(graphHeadString.getLabel(), graphHead);
}
}