org.archive.giraph.InDegreeCountComputationVertexWithTextValue.java Source code

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Here is the source code for org.archive.giraph.InDegreeCountComputationVertexWithTextValue.java

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/*
 * 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.archive.giraph;

import org.apache.giraph.graph.BasicComputation;
import org.apache.giraph.edge.Edge;
import org.apache.giraph.graph.Vertex;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;

/**
 * Simple function to return the in degree for each vertex.
 */
@Algorithm(name = "Indegree Count for vertices with Text values")
public class InDegreeCountComputationVertexWithTextValue extends BasicComputation<LongWritable, Text, Text, Text> {

    @Override
    public void compute(Vertex<LongWritable, Text, Text> vertex, Iterable<Text> messages) {
        if (getSuperstep() == 0) {
            Iterable<Edge<LongWritable, Text>> edges = vertex.getEdges();
            for (Edge<LongWritable, Text> edge : edges) {
                sendMessage(edge.getTargetVertexId(), new Text("1"));
            }
        } else {
            long sum = 0;
            for (Text message : messages) {
                sum++;
            }
            Text vertexValue = vertex.getValue();
            vertexValue.set(Double.toString(sum));
            vertex.setValue(vertexValue);
            vertex.voteToHalt();
        }
    }
}