| /* |
| 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.edgent.analytics.math3.stat; |
| |
| import org.apache.commons.math3.stat.descriptive.AbstractStorelessUnivariateStatistic; |
| import org.apache.commons.math3.stat.descriptive.StorelessUnivariateStatistic; |
| |
| /** |
| * The number of items in the collection being aggregated. |
| * |
| * Need this semi-hack to be able to capture the number |
| * of items in an aggregation in a ResultMap. |
| */ |
| class Count extends AbstractStorelessUnivariateStatistic { |
| int n; |
| |
| @Override |
| public long getN() { |
| return n; |
| } |
| |
| @Override |
| public void clear() { |
| n = 0; |
| } |
| |
| @Override |
| public StorelessUnivariateStatistic copy() { |
| return new Count(); |
| } |
| |
| @Override |
| public double getResult() { |
| return n; |
| } |
| |
| @Override |
| public void increment(double arg0) { |
| n++; |
| } |
| |
| } |