1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * 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 and
16 * limitations under the License.
17 */
18
19 package org.apache.giraph.examples;
20
21 import org.apache.giraph.graph.BasicComputation;
22 import org.apache.giraph.graph.Vertex;
23 import org.apache.hadoop.io.Writable;
24 import org.apache.hadoop.io.WritableComparable;
25
26 import java.io.IOException;
27
28 /**
29 * User applications can subclass IdentityComputation, which
30 * simply prints the results that have been read for testing IO related
31 * jobs under any inputformat
32 *
33 * @param <I> Vertex index value
34 * @param <V> Vertex value
35 * @param <E> Edge value
36 * @param <M> Message value
37 */
38 @SuppressWarnings("rawtypes")
39 public class IdentityComputation<I extends WritableComparable,
40 V extends Writable, E extends Writable, M extends Writable>
41 extends BasicComputation<I, V, E, M> {
42 @Override
43 public void compute(Vertex<I, V, E> vertex,
44 Iterable<M> messages) throws IOException {
45 vertex.voteToHalt();
46 }
47 }