/*
* -----------------------------------------------------------------------\
* PerfCake
*
* Copyright (C) 2010 - 2016 the original author or authors.
*
* Licensed 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.perfcake.reporting.reporter.accumulator;
/**
* Accumulates an harmonic mean over a set of the number of recently reported values.
*
* @author <a href="mailto:marvenec@gmail.com">Martin Večeřa</a>
* @author <a href="mailto:pavel.macik@gmail.com">Pavel Macík</a>
*/
public class SlidingWindowHarmonicMeanAccumulator extends AbstractSlidingWindowAccumulator<Double> {
/**
* Creates a new harmonic mean accumulator with the sliding window of a given size.
*
* @param windowSize
* Size of the sliding window.
*/
public SlidingWindowHarmonicMeanAccumulator(final int windowSize) {
super(windowSize);
}
@SuppressWarnings("unchecked")
@Override
public void add(final Double number) {
fifo.add(1.0 / number);
}
@Override
public Double getResult() {
double accum = 0;
double size;
synchronized (fifo) {
for (final Object o : fifo) {
accum = accum + (Double) o;
}
size = fifo.size();
}
return size == 0 ? 0d : size / accum;
}
}