com.netflix.servo.monitor.DoubleGauge Maven / Gradle / Ivy
/*
* Copyright 2011-2018 Netflix, 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.netflix.servo.monitor;
import com.google.common.util.concurrent.AtomicDouble;
import com.netflix.servo.SpectatorContext;
import com.netflix.servo.annotations.DataSourceType;
import com.netflix.servo.tag.TagList;
import com.netflix.spectator.api.Id;
/**
* A {@link Gauge} that reports a double value.
*/
public class DoubleGauge extends AbstractMonitor
implements Gauge, SpectatorMonitor {
private final MonitorConfig baseConfig;
private final AtomicDouble number;
private final SpectatorContext.LazyGauge spectatorGauge;
/**
* Create a new instance with the specified configuration.
*
* @param config configuration for this gauge
*/
public DoubleGauge(MonitorConfig config) {
super(config.withAdditionalTag(DataSourceType.GAUGE));
baseConfig = config;
number = new AtomicDouble(0.0);
spectatorGauge = SpectatorContext.gauge(config);
}
/**
* Set the current value.
*/
public void set(Double n) {
spectatorGauge.set(n);
number.set(n);
}
/**
* Returns a reference to the {@link com.google.common.util.concurrent.AtomicDouble}.
*/
public AtomicDouble getNumber() {
return number;
}
/**
* {@inheritDoc}
*/
@Override
public void initializeSpectator(TagList tags) {
Id id = SpectatorContext.createId(baseConfig.withAdditionalTags(tags));
spectatorGauge.setId(id);
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
DoubleGauge that = (DoubleGauge) o;
return getConfig().equals(that.getConfig())
&& getValue().equals(that.getValue());
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
int result = config.hashCode();
final int n = Double.valueOf(number.get()).hashCode();
result = 31 * result + n;
return result;
}
/**
* {@inheritDoc}
*/
@Override
public Double getValue(int pollerIdx) {
// we return the actual value at the time of the call and not a reference
// to the atomic number so the value doesn't change and is also available to jmx viewers
return number.get();
}
/**
* {@inheritDoc}
*/
@Override
public String toString() {
return "DoubleGauge{config=" + config + ", number=" + number + '}';
}
}