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 package org.apache.giraph.factories; 19 20 import org.apache.giraph.conf.GiraphConfigurationSettable; 21 import org.apache.giraph.conf.ImmutableClassesGiraphConfiguration; 22 import org.apache.giraph.utils.WritableUtils; 23 import org.apache.hadoop.io.WritableComparable; 24 25 /** 26 * Default {@link VertexIdFactory} that simply uses the default 27 * constructor for the vertex ID class. 28 * 29 * @param <I> Vertex ID 30 */ 31 public class DefaultVertexIdFactory<I extends WritableComparable> 32 implements VertexIdFactory<I>, GiraphConfigurationSettable { 33 /** Cached vertex value class. */ 34 private Class<I> vertexIdClass; 35 /** Configuration */ 36 private ImmutableClassesGiraphConfiguration conf; 37 38 @Override 39 public void setConf(ImmutableClassesGiraphConfiguration conf) { 40 this.conf = conf; 41 vertexIdClass = conf.getVertexIdClass(); 42 } 43 44 @Override 45 public I newInstance() { 46 return WritableUtils.createWritable(vertexIdClass, conf); 47 } 48 }