| /** |
| * 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.apex.malhar.lib.dimensions.aggregator; |
| |
| import org.apache.apex.malhar.lib.appdata.gpo.GPOUtils; |
| import org.apache.apex.malhar.lib.appdata.schemas.FieldsDescriptor; |
| import org.apache.apex.malhar.lib.appdata.schemas.Type; |
| import org.apache.apex.malhar.lib.dimensions.DimensionsEvent; |
| import org.apache.apex.malhar.lib.dimensions.DimensionsEvent.Aggregate; |
| import org.apache.apex.malhar.lib.dimensions.DimensionsEvent.InputEvent; |
| |
| import com.datatorrent.api.annotation.Name; |
| |
| /** |
| * <p> |
| * This aggregator creates an aggregate out of the last {@link InputEvent} encountered by this aggregator. All previous |
| * {@link InputEvent}s are ignored. |
| * </p> |
| * <p> |
| * <b>Note:</b> when aggregates are combined in a unifier it is not possible to tell which came first or last, so |
| * one is picked arbitrarily to be the last. |
| * </p> |
| * |
| * @since 3.1.0 |
| */ |
| @Name("LAST") |
| public class AggregatorLast extends AbstractIncrementalAggregator |
| { |
| private static final long serialVersionUID = 20154301647L; |
| |
| public AggregatorLast() |
| { |
| //Do nothing |
| } |
| |
| @Override |
| public Aggregate getGroup(InputEvent src, int aggregatorIndex) |
| { |
| Aggregate aggregate = super.getGroup(src, aggregatorIndex); |
| |
| GPOUtils.indirectCopy(aggregate.getAggregates(), src.getAggregates(), context.indexSubsetAggregates); |
| |
| return aggregate; |
| } |
| |
| @Override |
| public Type getOutputType(Type inputType) |
| { |
| return AggregatorUtils.IDENTITY_TYPE_MAP.get(inputType); |
| } |
| |
| @Override |
| public void aggregate(Aggregate dest, InputEvent src) |
| { |
| GPOUtils.indirectCopy(dest.getAggregates(), src.getAggregates(), context.indexSubsetAggregates); |
| } |
| |
| @Override |
| public void aggregate(Aggregate dest, Aggregate src) |
| { |
| DimensionsEvent.copy(dest, src); |
| } |
| |
| @Override |
| public FieldsDescriptor getMetaDataDescriptor() |
| { |
| return null; |
| } |
| } |