/*
* 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.giraph.examples;
import org.apache.giraph.graph.BasicComputation;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.giraph.graph.Vertex;
import java.io.IOException;
/**
* Simple function to return the out degree for each vertex.
*/
@Algorithm(
name = "Outdegree Count"
)
public class SimpleOutDegreeCountComputation extends BasicComputation<
LongWritable, LongWritable, DoubleWritable, DoubleWritable> {
@Override
public void compute(
Vertex<LongWritable, LongWritable, DoubleWritable> vertex,
Iterable<DoubleWritable> messages) throws IOException {
LongWritable vertexValue = vertex.getValue();
vertexValue.set(vertex.getNumEdges());
vertex.setValue(vertexValue);
vertex.voteToHalt();
}
}