| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.giraph.master; |
| |
| import org.apache.giraph.aggregators.Aggregator; |
| import org.apache.giraph.aggregators.AggregatorUsage; |
| import org.apache.hadoop.io.Writable; |
| |
| /** |
| * Master compute can access and change aggregators through this interface |
| */ |
| public interface MasterAggregatorUsage extends AggregatorUsage { |
| /** |
| * Register an aggregator in preSuperstep() and/or preApplication(). This |
| * aggregator will have its value reset at the end of each super step. |
| * |
| * @param name of aggregator |
| * @param aggregatorClass Class type of the aggregator |
| * @param <A> Aggregator type |
| * @return True iff aggregator wasn't already registered |
| */ |
| <A extends Writable> boolean registerAggregator(String name, |
| Class<? extends Aggregator<A>> aggregatorClass) throws |
| InstantiationException, IllegalAccessException; |
| |
| /** |
| * Register persistent aggregator in preSuperstep() and/or |
| * preApplication(). This aggregator will not reset value at the end of |
| * super step. |
| * |
| * @param name of aggregator |
| * @param aggregatorClass Class type of the aggregator |
| * @param <A> Aggregator type |
| * @return True iff aggregator wasn't already registered |
| */ |
| <A extends Writable> boolean registerPersistentAggregator(String name, |
| Class<? extends Aggregator<A>> aggregatorClass) throws |
| InstantiationException, IllegalAccessException; |
| |
| /** |
| * Sets value of an aggregator. |
| * |
| * @param name Name of aggregator |
| * @param value Value to set |
| * @param <A> Aggregated value |
| */ |
| <A extends Writable> void setAggregatedValue(String name, A value); |
| } |