1/*2 * Licensed to the Apache Software Foundation (ASF) under one3 * or more contributor license agreements. See the NOTICE file4 * distributed with this work for additional information5 * regarding copyright ownership. The ASF licenses this file6 * to you under the Apache License, Version 2.0 (the7 * "License"); you may not use this file except in compliance8 * with the License. You may obtain a copy of the License at9 *10 * http://www.apache.org/licenses/LICENSE-2.011 *12 * Unless required by applicable law or agreed to in writing, software13 * distributed under the License is distributed on an "AS IS" BASIS,14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.15 * See the License for the specific language governing permissions and16 * limitations under the License.17 */1819package org.apache.giraph.examples;
2021import org.apache.giraph.graph.BasicComputation;
22import org.apache.giraph.graph.Vertex;
23import org.apache.hadoop.io.FloatWritable;
24import org.apache.hadoop.io.IntWritable;
25import org.apache.hadoop.io.LongWritable;
26import org.apache.log4j.Logger;
2728import java.io.IOException;
2930/**31 * Test whether messages can go through a combiner.32 */33publicclassSimpleCombinerComputationextends34 BasicComputation<LongWritable, IntWritable, FloatWritable, IntWritable> {
35/** Class logger */36privatestatic Logger LOG = Logger.getLogger(SimpleCombinerComputation.class);
3738 @Override
39publicvoid compute(
40 Vertex<LongWritable, IntWritable, FloatWritable> vertex,
41 Iterable<IntWritable> messages) throws IOException {
42if (vertex.getId().equals(new LongWritable(2))) {
43 sendMessage(new LongWritable(1), new IntWritable(101));
44 sendMessage(new LongWritable(1), new IntWritable(102));
45 sendMessage(new LongWritable(1), new IntWritable(103));
46 }
47if (!vertex.getId().equals(new LongWritable(1))) {
48 vertex.voteToHalt();
49 } else {
50// Check the messages51int sum = 0;
52int num = 0;
53for (IntWritable message : messages) {
54 sum += message.get();
55 num++;
56 }
57 LOG.info("TestCombinerVertex: Received a sum of " + sum +
58" (should have 306 with a single message value)");
5960if (num == 1 && sum == 306) {
61 vertex.voteToHalt();
62 }
63 }
64if (getSuperstep() > 3) {
65thrownew IllegalStateException(
66"TestCombinerVertex: Vertex 1 failed to receive " +
67"messages in time");
68 }
69 }
70 }