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.io; 20 21 import java.io.IOException; 22 23 import org.apache.hadoop.io.Writable; 24 import org.apache.hadoop.io.WritableComparable; 25 import org.apache.hadoop.mapreduce.TaskAttemptContext; 26 27 /** 28 * abstract class which can only write edges 29 * 30 * @param <I> Vertex id 31 * @param <V> Vertex value 32 * @param <E> Edge value 33 */ 34 @SuppressWarnings("rawtypes") 35 public abstract class EdgeOutputFormat< 36 I extends WritableComparable, V extends Writable, 37 E extends Writable> extends 38 OutputFormat<I, V, E> { 39 /** 40 * Create an edge writer for a given split. The framework will call 41 * {@link EdgeWriter#initialize(TaskAttemptContext)} before 42 * the split is used. 43 * 44 * @param context the information about the task 45 * @return a new vertex writer 46 * @throws IOException 47 * @throws InterruptedException 48 */ 49 public abstract EdgeWriter<I, V, E> createEdgeWriter( 50 TaskAttemptContext context) throws IOException, InterruptedException; 51 }