com.netflix.spectator.api.NoopRegistry Maven / Gradle / Ivy
/*
* Copyright 2014-2019 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.Collections;
import java.util.Iterator;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
* Registry implementation that does nothing. This is typically used to allow for performance tests
* to see how much overhead is being added by instrumentation. This implementation tries to do the
* minimum amount possible without requiring code changes for users.
*/
public final class NoopRegistry implements Registry {
// Since we don't know how callers might be using this a noop implementation
// of the map could cause unexpected issues.
private final ConcurrentMap state = new ConcurrentHashMap<>();
@Override public Clock clock() {
return Clock.SYSTEM;
}
@Override public Id createId(String name) {
return NoopId.INSTANCE;
}
@Override public Id createId(String name, Iterable tags) {
return NoopId.INSTANCE;
}
@Override public void register(Meter meter) {
}
@Override public ConcurrentMap state() {
return state;
}
@Override public Counter counter(Id id) {
return NoopCounter.INSTANCE;
}
@Override public DistributionSummary distributionSummary(Id id) {
return NoopDistributionSummary.INSTANCE;
}
@Override public Timer timer(Id id) {
return NoopTimer.INSTANCE;
}
@Override public Gauge gauge(Id id) {
return NoopGauge.INSTANCE;
}
@Override public Gauge maxGauge(Id id) {
return NoopGauge.INSTANCE;
}
@Override public Meter get(Id id) {
return null;
}
@Override public Iterator iterator() {
return Collections.emptyList().iterator();
}
@Override public void propagate(String msg, Throwable t) {
// Since everything will have the same id when using this registry, it can result
// in type errors when checking against the state, see #503.
}
@Override public void propagate(Throwable t) {
}
}