com.uber.m3.tally.GaugeImpl Maven / Gradle / Ivy
// Copyright (c) 2017 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package com.uber.m3.tally;
import com.uber.m3.util.ImmutableMap;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;
/**
* Default implementation of a {@link Gauge}.
*/
class GaugeImpl implements Gauge {
private AtomicBoolean updated = new AtomicBoolean(false);
private AtomicLong curr = new AtomicLong(0);
@Override
public void update(double value) {
curr.set(Double.doubleToLongBits(value));
updated.set(true);
}
double value() {
return Double.longBitsToDouble(curr.get());
}
void report(String name, ImmutableMap tags, StatsReporter reporter) {
if (updated.getAndSet(false)) {
reporter.reportGauge(name, tags, value());
}
}
double snapshot() {
return value();
}
}