| /** |
| * 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 |
| * |
| * 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 org.apache.hadoop.hbase.metrics; |
| |
| import java.util.Optional; |
| |
| import org.apache.hadoop.hbase.HBaseInterfaceAudience; |
| import org.apache.yetus.audience.InterfaceAudience; |
| import org.apache.yetus.audience.InterfaceStability; |
| |
| /** |
| * General purpose factory for creating various metrics. |
| */ |
| @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.COPROC) |
| @InterfaceStability.Evolving |
| public interface MetricRegistry extends MetricSet { |
| |
| /** |
| * Get or construct a {@link Timer} used to measure durations and report rates. |
| * |
| * @param name the name of the timer. |
| * @return An instance of {@link Timer}. |
| */ |
| Timer timer(String name); |
| |
| /** |
| * Get or construct a {@link Histogram} used to measure a distribution of values. |
| * |
| * @param name The name of the Histogram. |
| * @return An instance of {@link Histogram}. |
| */ |
| Histogram histogram(String name); |
| |
| /** |
| * Get or construct a {@link Meter} used to measure durations and report distributions (a |
| * combination of a {@link Timer} and a {@link Histogram}. |
| * |
| * @param name The name of the Meter. |
| * @return An instance of {@link Meter}. |
| */ |
| Meter meter(String name); |
| |
| /** |
| * Get or construct a {@link Counter} used to track a mutable number. |
| * |
| * @param name The name of the Counter |
| * @return An instance of {@link Counter}. |
| */ |
| Counter counter(String name); |
| |
| /** |
| * Register a {@link Gauge}. The Gauge will be invoked at a period defined by the implementation |
| * of {@link MetricRegistry}. |
| * @param name The name of the Gauge. |
| * @param gauge A callback to compute the current value. |
| * @return the registered gauge, or the existing gauge |
| */ |
| <T> Gauge<T> register(String name, Gauge<T> gauge); |
| |
| /** |
| * Registers the {@link Metric} with the given name if there does not exist one with the same |
| * name. Returns the newly registered or existing Metric. |
| * @param name The name of the Metric. |
| * @param metric the metric to register |
| * @return the registered metric, or the existing metrid |
| */ |
| Metric register(String name, Metric metric); |
| |
| /** |
| * Registers the {@link Metric}s in the given MetricSet. |
| * @param metricSet set of metrics to register. |
| */ |
| void registerAll(MetricSet metricSet); |
| |
| /** |
| * Returns previously registered metric with the name if any. |
| * @param name the name of the metric |
| * @return previously registered metric |
| */ |
| Optional<Metric> get(String name); |
| |
| /** |
| * Removes the metric with the given name. |
| * |
| * @param name the name of the metric |
| * @return true if the metric is removed. |
| */ |
| boolean remove(String name); |
| |
| /** |
| * Return the MetricRegistryInfo object for this registry. |
| * @return MetricRegistryInfo describing the registry. |
| */ |
| @InterfaceAudience.Private |
| MetricRegistryInfo getMetricRegistryInfo(); |
| } |