001/* 002 * Copyright (c) 2016-2017 Chris K Wensel <chris@wensel.net>. All Rights Reserved. 003 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved. 004 * 005 * Project and contact information: http://www.cascading.org/ 006 * 007 * This file is part of the Cascading project. 008 * 009 * Licensed under the Apache License, Version 2.0 (the "License"); 010 * you may not use this file except in compliance with the License. 011 * You may obtain a copy of the License at 012 * 013 * http://www.apache.org/licenses/LICENSE-2.0 014 * 015 * Unless required by applicable law or agreed to in writing, software 016 * distributed under the License is distributed on an "AS IS" BASIS, 017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 018 * See the License for the specific language governing permissions and 019 * limitations under the License. 020 */ 021 022package cascading.tuple.collect; 023 024import java.util.Collection; 025 026import cascading.provider.CascadingFactory; 027import cascading.tuple.Tuple; 028 029/** 030 * Interface TupleCollectionFactory allows developers to plugin alternative implementations of a "tuple collection" 031 * used to back in memory "join" and "co-group" operations. Typically these implementations are 032 * "spillable", in that to prevent using up all memory in the JVM, after some threshold is met or event 033 * is triggered, values are persisted to disk. 034 * <p> 035 * The {@link java.util.Collection} classes returned must take a {@link cascading.tuple.Tuple} as a value. 036 * <p> 037 * If the Collection implementation implements the {@link Spillable} interface, it will receive a {@link Spillable.SpillListener} 038 * instance that calls back to the appropriate logging mechanism for the platform. 039 * <p> 040 * The class {@link SpillableTupleList} may be used as a base class. 041 * 042 * @see cascading.tuple.hadoop.collect.HadoopTupleCollectionFactory 043 * @see SpillableTupleList 044 * @see cascading.tuple.hadoop.collect.HadoopSpillableTupleList 045 * @see TupleMapFactory 046 * @see cascading.tuple.hadoop.collect.HadoopTupleMapFactory 047 */ 048public interface TupleCollectionFactory<Config> extends CascadingFactory<Config, Collection<Tuple>> 049 { 050 String TUPLE_COLLECTION_FACTORY = "cascading.factory.tuple.collection.classname"; 051 }