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.io.formats;
2021import org.apache.giraph.io.EdgeReader;
22import org.apache.giraph.io.ReverseEdgeDuplicator;
23import org.apache.hadoop.io.IntWritable;
24import org.apache.hadoop.io.NullWritable;
25import org.apache.hadoop.mapreduce.InputSplit;
26import org.apache.hadoop.mapreduce.TaskAttemptContext;
2728import java.io.IOException;
2930/**31 * Simple text-based {@link org.apache.giraph.io.EdgeInputFormat} for32 * unweighted graphs with int ids.33 *34 * Each line consists of: source_vertex, target_vertex35 *36 * This version also creates the reverse edges.37 */38publicclassIntNullReverseTextEdgeInputFormat39extendsIntNullTextEdgeInputFormat {
40 @Override
41public EdgeReader<IntWritable, NullWritable> createEdgeReader(
42 InputSplit split, TaskAttemptContext context) throws IOException {
43 EdgeReader<IntWritable, NullWritable> edgeReader =
44super.createEdgeReader(split, context);
45 edgeReader.setConf(getConf());
46returnnew ReverseEdgeDuplicator<IntWritable, NullWritable>(edgeReader);
47 }
48 }