EdColeman commented on code in PR #4542: URL: https://github.com/apache/accumulo/pull/4542#discussion_r1598787088
########## server/base/src/main/java/org/apache/accumulo/server/metrics/NoopMetrics.java: ########## @@ -0,0 +1,79 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 + * + * https://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 org.apache.accumulo.server.metrics; + +import java.util.concurrent.atomic.AtomicInteger; + +import io.micrometer.core.instrument.Counter; +import io.micrometer.core.instrument.DistributionSummary; +import io.micrometer.core.instrument.FunctionTimer; +import io.micrometer.core.instrument.Gauge; +import io.micrometer.core.instrument.Meter; +import io.micrometer.core.instrument.Tags; +import io.micrometer.core.instrument.Timer; +import io.micrometer.core.instrument.noop.NoopCounter; +import io.micrometer.core.instrument.noop.NoopDistributionSummary; +import io.micrometer.core.instrument.noop.NoopFunctionTimer; +import io.micrometer.core.instrument.noop.NoopGauge; +import io.micrometer.core.instrument.noop.NoopTimer; + +/** + * Convenience utility class to return micrometer noop metrics. Initialization of the metrics system + * registry can be delayed so that common tags with values determined at runtime (for example, port + * numbers). Initializing meters that are create from the registry at initialization with a noop + * implementation prevents NPEs if something tries to record a metric value before the + * initialization has run. + */ +public class NoopMetrics { + private static AtomicInteger idCount = new AtomicInteger(0); + + private NoopMetrics() {} + + public static Counter useNoopCounter() { + return new NoopCounter(noopId(Meter.Type.COUNTER)); + } + + public static Gauge useNoopGauge() { + return new NoopGauge(noopId(Meter.Type.GAUGE)); + } + + public static DistributionSummary useNoopDistributionSummary() { + return new NoopDistributionSummary(noopId(Meter.Type.DISTRIBUTION_SUMMARY)); + } + + public static Timer useNoopTimer() { + return new NoopTimer(noopId(Meter.Type.TIMER)); + } + + public static FunctionTimer useNoopFunctionTimer() { + return new NoopFunctionTimer(noopId(Meter.Type.TIMER)); + } + + /** + * provide a unique id to guard against the id being used as a key. + */ + private static Meter.Id noopId(final Meter.Type type) { + return new Meter.Id(uniqueName(), Tags.of("noop", "none"), "", "", type); Review Comment: What would be the benefit? They should never be registered and are replaced when registration occurs. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
