/*
* 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.flink.test.iterative.nephele.customdanglingpagerank;
import java.util.Iterator;
import org.apache.flink.api.common.functions.AbstractRichFunction;
import org.apache.flink.api.common.functions.FlatCombineFunction;
import org.apache.flink.api.common.functions.GroupReduceFunction;
import org.apache.flink.test.iterative.nephele.customdanglingpagerank.types.VertexWithRank;
import org.apache.flink.util.Collector;
public class CustomRankCombiner extends AbstractRichFunction implements GroupReduceFunction<VertexWithRank, VertexWithRank>,
FlatCombineFunction<VertexWithRank>
{
private static final long serialVersionUID = 1L;
private final VertexWithRank accumulator = new VertexWithRank();
@Override
public void reduce(Iterable<VertexWithRank> records, Collector<VertexWithRank> out) throws Exception {
throw new UnsupportedOperationException();
}
@Override
public void combine(Iterable<VertexWithRank> recordsIterable, Collector<VertexWithRank> out) throws Exception {
final Iterator<VertexWithRank> records = recordsIterable.iterator();
VertexWithRank next = records.next();
this.accumulator.setVertexID(next.getVertexID());
double rank = next.getRank();
while (records.hasNext()) {
rank += records.next().getRank();
}
this.accumulator.setRank(rank);
out.collect(this.accumulator);
}
}