com.hotels.styx.api.metrics.codahale.CodaHaleMetricRegistry Maven / Gradle / Ivy
/*
Copyright (C) 2013-2018 Expedia 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.hotels.styx.api.metrics.codahale;
import com.codahale.metrics.Counter;
import com.codahale.metrics.Gauge;
import com.codahale.metrics.Histogram;
import com.codahale.metrics.Meter;
import com.codahale.metrics.Metric;
import com.codahale.metrics.MetricFilter;
import com.codahale.metrics.MetricRegistryListener;
import com.codahale.metrics.Timer;
import com.hotels.styx.api.metrics.MetricRegistry;
import com.hotels.styx.api.metrics.ScopedMetricRegistry;
import java.util.Map;
import java.util.SortedMap;
import java.util.SortedSet;
/**
* A {@link MetricRegistry} that acts as an adapter for Codahale's {@link com.codahale.metrics.MetricRegistry}.
*/
public class CodaHaleMetricRegistry implements MetricRegistry {
private final com.codahale.metrics.MetricRegistry metricRegistry;
/**
* Construct an adapter from an existing codahale registry.
*
* @param metricRegistry codehale {@link com.codahale.metrics.MetricRegistry}
*/
public CodaHaleMetricRegistry(com.codahale.metrics.MetricRegistry metricRegistry) {
this.metricRegistry = metricRegistry;
}
/**
* Construct an adapter using a new codahale registry.
*/
public CodaHaleMetricRegistry() {
this(new com.codahale.metrics.MetricRegistry());
}
public com.codahale.metrics.MetricRegistry getMetricRegistry() {
return metricRegistry;
}
@Override
public MetricRegistry scope(String name) {
return new ScopedMetricRegistry(name, this);
}
@Override
public T register(String name, T metric) throws IllegalArgumentException {
return metricRegistry.register(name, metric);
}
@Override
public boolean deregister(String name) {
return metricRegistry.remove(name);
}
@Override
public Counter counter(String name) {
return metricRegistry.counter(name);
}
@Override
public Histogram histogram(String name) {
return metricRegistry.histogram(name);
}
@Override
public Meter meter(String name) {
return metricRegistry.meter(name);
}
@Override
public Timer timer(String name) {
Map metrics = metricRegistry.getMetrics();
Metric metric = metrics.get(name);
if (metric instanceof Timer) {
return (Timer) metric;
}
if (metric == null) {
try {
return register(name, newTimer());
} catch (IllegalArgumentException e) {
Metric added = metrics.get(name);
if (added instanceof Timer) {
return (Timer) added;
}
}
}
throw new IllegalArgumentException(name + " is already used for a different type of metric");
}
private Timer newTimer() {
return new SampleCountFromSnapshotTimer(new SlidingWindowHistogramReservoir());
}
@Override
public void addListener(MetricRegistryListener listener) {
this.metricRegistry.addListener(listener);
}
@Override
public void removeListener(MetricRegistryListener listener) {
this.metricRegistry.removeListener(listener);
}
@Override
public SortedSet getNames() {
return metricRegistry.getNames();
}
@Override
public SortedMap getGauges() {
return metricRegistry.getGauges();
}
@Override
public SortedMap getGauges(MetricFilter filter) {
return metricRegistry.getGauges(filter);
}
@Override
public SortedMap getCounters() {
return metricRegistry.getCounters();
}
@Override
public SortedMap getCounters(MetricFilter filter) {
return metricRegistry.getCounters(filter);
}
@Override
public SortedMap getHistograms() {
return metricRegistry.getHistograms();
}
@Override
public SortedMap getHistograms(MetricFilter filter) {
return metricRegistry.getHistograms(filter);
}
@Override
public SortedMap getMeters() {
return metricRegistry.getMeters();
}
@Override
public SortedMap getMeters(MetricFilter filter) {
return metricRegistry.getMeters(filter);
}
@Override
public SortedMap getTimers() {
return metricRegistry.getTimers();
}
@Override
public SortedMap getTimers(MetricFilter filter) {
return metricRegistry.getTimers(filter);
}
/**
* Concatenates elements to form a dotted name, omitting null values and empty strings.
*
* @param name the first element of the name
* @param names the remaining elements of the name
* @return {@code name} and {@code names} concatenated by dots
*/
public static String name(String name, String... names) {
StringBuilder builder = new StringBuilder();
append(builder, name);
if (names != null) {
for (String s : names) {
append(builder, s);
}
}
return builder.toString();
}
/**
* Concatenates a class name and elements to form a dotted name, omitting null values and empty strings.
*
* @param klass the first element of the name
* @param names the remaining elements of the name
* @return {@code klass} and {@code names} concatenated by dots
*/
public static String name(Class klass, String... names) {
return name(klass.getName(), names);
}
private static void append(StringBuilder builder, String part) {
if (part != null && !part.isEmpty()) {
if (builder.length() > 0) {
builder.append('.');
}
builder.append(part);
}
}
private static class SampleCountFromSnapshotTimer extends Timer {
public SampleCountFromSnapshotTimer(SlidingWindowHistogramReservoir slidingWindowHistogramReservoir) {
super(slidingWindowHistogramReservoir);
}
@Override
public long getCount() {
return (long) getSnapshot().size();
}
}
}