com.netflix.spectator.api.AbstractDefaultDynamicMeter Maven / Gradle / Ivy
/**
* Copyright 2015 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.spectator.api;
import java.util.function.Function;
/**
* Base class for dynamic meters that provides implementations for the core
* interface methods.
*/
abstract class AbstractDefaultDynamicMeter implements Meter {
private final DynamicId id;
private final Function meterResolver;
/**
* Creates a new dynamic meter.
*
* @param id the dynamic id for the meter
* @param meterResolver the function to map a resolved id to concrete metric
*/
AbstractDefaultDynamicMeter(DynamicId id, Function meterResolver) {
this.id = id;
this.meterResolver = meterResolver;
}
/**
* Resolve the dynamic id to the current metric instance.
*/
protected final T resolveToCurrentMeter() {
return meterResolver.apply(id.resolveToId());
}
@Override
public final Id id() {
return resolveToCurrentMeter().id();
}
@Override
public final Iterable measure() {
return resolveToCurrentMeter().measure();
}
@Override
public final boolean hasExpired() {
// Without tracking all of the regular meters that are created from this
// dynamic meter we don't have any way of knowing whether the "master"
// counter has expired. Instead of adding the tracking, we choose to
// rely on the regular expiration mechanism for the underlying meters.
return false;
}
}