com.codahale.metrics.health.SharedHealthCheckRegistries Maven / Gradle / Ivy
package com.codahale.metrics.health;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicReference;
/**
* A map of shared, named health registries.
*/
public class SharedHealthCheckRegistries {
private static final ConcurrentMap REGISTRIES =
new ConcurrentHashMap();
private static AtomicReference defaultRegistryName = new AtomicReference();
/* Visible for testing */
static void setDefaultRegistryName(AtomicReference defaultRegistryName) {
SharedHealthCheckRegistries.defaultRegistryName = defaultRegistryName;
}
private SharedHealthCheckRegistries() { /* singleton */ }
public static void clear() {
REGISTRIES.clear();
}
public static Set names() {
return REGISTRIES.keySet();
}
public static void remove(String key) {
REGISTRIES.remove(key);
}
public static HealthCheckRegistry add(String name, HealthCheckRegistry registry) {
return REGISTRIES.putIfAbsent(name, registry);
}
public static HealthCheckRegistry getOrCreate(String name) {
final HealthCheckRegistry existing = REGISTRIES.get(name);
if (existing == null) {
final HealthCheckRegistry created = new HealthCheckRegistry();
final HealthCheckRegistry raced = add(name, created);
if (raced == null) {
return created;
}
return raced;
}
return existing;
}
/**
* Creates a new registry and sets it as the default one under the provided name.
*
* @param name the registry name
* @return the default registry
* @throws IllegalStateException if the name has already been set
*/
public synchronized static HealthCheckRegistry setDefault(String name) {
final HealthCheckRegistry registry = getOrCreate(name);
return setDefault(name, registry);
}
/**
* Sets the provided registry as the default one under the provided name
*
* @param name the default registry name
* @param healthCheckRegistry the default registry
* @throws IllegalStateException if the default registry has already been set
*/
public static HealthCheckRegistry setDefault(String name, HealthCheckRegistry healthCheckRegistry) {
if (defaultRegistryName.compareAndSet(null, name)) {
add(name, healthCheckRegistry);
return healthCheckRegistry;
}
throw new IllegalStateException("Default health check registry is already set.");
}
/**
* Gets the name of the default registry, if it has been set
*
* @return the default registry
* @throws IllegalStateException if the default has not been set
*/
public static HealthCheckRegistry getDefault() {
final String name = defaultRegistryName.get();
if (name != null) {
return getOrCreate(name);
}
throw new IllegalStateException("Default registry name has not been set.");
}
}