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.edge; 20 21 import org.apache.giraph.conf.GiraphConfigurationSettable; 22 import org.apache.hadoop.io.Writable; 23 24 /** 25 * Implementations of this interface can decide whether 26 * we should create a vertex when it is not present in vertex input 27 * but exists in edge input. 28 * 29 * @param <I> vertex id 30 */ 31 public interface CreateSourceVertexCallback<I extends Writable> 32 extends GiraphConfigurationSettable { 33 34 /** 35 * Should we create a vertex that doesn't exist in vertex input 36 * but only exists in edge input 37 * @param vertexId the id of vertex to be created 38 * @return true if we should create a vertex 39 */ 40 boolean shouldCreateSourceVertex(I vertexId); 41 42 }