1 /* 2 * Copyright (c) 2014, 2015, Dynatrace and/or its affiliates. All rights reserved. 3 * 4 * This file is part of the Lock Contention Tracing Subsystem for the HotSpot 5 * Virtual Machine, which is developed at Christian Doppler Laboratory on 6 * Monitoring and Evolution of Very-Large-Scale Software Systems. Please 7 * contact us at <http://mevss.jku.at/> if you need additional information 8 * or have any questions. 9 * 10 * This code is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License version 2 only, as 12 * published by the Free Software Foundation. 13 * 14 * This code is distributed in the hope that it will be useful, but WITHOUT 15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 17 * version 2 for more details (a copy is included in the LICENSE file that 18 * accompanied this code). 19 * 20 * You should have received a copy of the GNU General Public License version 21 * 2 along with this work. If not, see <http://www.gnu.org/licenses/>. 22 * 23 */ 24 package sun.evtracing.processing.statistics.aggregator; 25 26 public abstract class AggregatorFactory<T extends Aggregator> { 27 private final AggregatorFactory<? extends Aggregator> nextFactory; 28 private final AggregationConfiguration configuration; 29 30 public AggregatorFactory(AggregationConfiguration configuration) { 31 this(null, configuration); 32 } 33 34 public AggregatorFactory(AggregatorFactory<? extends Aggregator> nextFactory, AggregationConfiguration configuration) { 35 this.nextFactory = nextFactory; 36 this.configuration = configuration; 37 } 38 39 public abstract T create(); 40 41 public abstract T merge(T x, T y); 42 43 public AggregationConfiguration configuration() { 44 return configuration; 45 } 46 47 T mergeChecked(Aggregator x, Aggregator y) { 48 if (x.factory() != this) { 49 throw new IllegalArgumentException("aggregator x not an instance of factory"); 50 } 51 if (y.factory() != this) { 52 throw new IllegalArgumentException("aggregator y not an instance of factory"); 53 } 54 @SuppressWarnings("unchecked") 55 T xt = (T) x; 56 @SuppressWarnings("unchecked") 57 T yt = (T) y; 58 return merge(xt, yt); 59 } 60 61 AggregatorFactory<? extends Aggregator> nextFactory() { 62 return nextFactory; 63 } 64 }