com.mongodb.internal.connection.ExponentiallyWeightedMovingAverage Maven / Gradle / Ivy
/*
* Copyright 2008-present MongoDB, Inc.
*
* 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 com.mongodb.internal.connection;
import com.mongodb.annotations.NotThreadSafe;
import static com.mongodb.assertions.Assertions.isTrueArgument;
@NotThreadSafe
class ExponentiallyWeightedMovingAverage {
private final double alpha;
private long average = -1;
ExponentiallyWeightedMovingAverage(final double alpha) {
isTrueArgument("alpha >= 0.0 and <= 1.0", alpha >= 0.0 && alpha <= 1.0);
this.alpha = alpha;
}
void reset() {
average = -1;
}
long addSample(final long sample) {
if (average == -1) {
average = sample;
} else {
average = (long) (alpha * sample + (1 - alpha) * average);
}
return average;
}
long getAverage() {
return average == -1 ? 0 : average;
}
}