| /* |
| * 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.scc; |
| |
| import java.io.IOException; |
| import java.util.List; |
| import java.util.regex.Pattern; |
| |
| import org.apache.giraph.edge.Edge; |
| import org.apache.giraph.edge.EdgeFactory; |
| import org.apache.giraph.io.formats.TextVertexInputFormat; |
| import org.apache.hadoop.io.LongWritable; |
| import org.apache.hadoop.io.NullWritable; |
| import org.apache.hadoop.io.Text; |
| import org.apache.hadoop.mapreduce.InputSplit; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| |
| import com.google.common.collect.Lists; |
| |
| /** |
| * Simple text-based {@link org.apache.giraph.io.VertexInputFormat} for |
| * unweighted graphs with long ids. |
| * |
| * Each line consists of: vertex neighbor1 neighbor2 ... |
| */ |
| public class SccLongLongNullTextInputFormat extends |
| TextVertexInputFormat<LongWritable, SccVertexValue, NullWritable> { |
| /** Separator of the vertex and neighbors */ |
| private static final Pattern SEPARATOR = Pattern.compile("[\t ]"); |
| |
| @Override |
| public TextVertexReader createVertexReader(InputSplit split, |
| TaskAttemptContext context) |
| throws IOException { |
| return new LongLongNullVertexReader(); |
| } |
| |
| /** |
| * Vertex reader associated with {@link SccLongLongNullTextInputFormat}. |
| */ |
| public class LongLongNullVertexReader extends |
| TextVertexReaderFromEachLineProcessed<String[]> { |
| /** Cached vertex id for the current line */ |
| private LongWritable id; |
| |
| @Override |
| protected String[] preprocessLine(Text line) throws IOException { |
| String[] tokens = SEPARATOR.split(line.toString()); |
| id = new LongWritable(Long.parseLong(tokens[0])); |
| return tokens; |
| } |
| |
| @Override |
| protected LongWritable getId(String[] tokens) throws IOException { |
| return id; |
| } |
| |
| @Override |
| protected SccVertexValue getValue(String[] tokens) throws IOException { |
| return new SccVertexValue(Long.parseLong(tokens[0])); |
| } |
| |
| @Override |
| protected Iterable<Edge<LongWritable, NullWritable>> getEdges( |
| String[] tokens) throws IOException { |
| List<Edge<LongWritable, NullWritable>> edges = |
| Lists.newArrayListWithCapacity(tokens.length - 1); |
| for (int n = 1; n < tokens.length; n++) { |
| edges.add(EdgeFactory.create( |
| new LongWritable(Long.parseLong(tokens[n])))); |
| } |
| return edges; |
| } |
| } |
| } |