org.apache.hadoop.metrics2.impl

Class JmxCacheBuster

java.lang.Object

org.apache.hadoop.metrics2.impl.JmxCacheBuster

@InterfaceAudience.Private
public class JmxCacheBuster
extends Object

JMX caches the beans that have been exported; even after the values are removed from hadoop's metrics system the keys and old values will still remain. This class stops and restarts the Hadoop metrics system, forcing JMX to clear the cache of exported metrics. This class need to be in the o.a.h.metrics2.impl namespace as many of the variables/calls used are package private.

Method Summary

Modifier and Type	Method and Description
static void	clearJmxCache() For JMX to forget about all previously exported metrics.
static void	restart() Restarts the stopped service.
static void	stop() Stops the clearing of JMX metrics and restarting the Hadoop metrics system.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

clearJmxCache

public static void clearJmxCache()

For JMX to forget about all previously exported metrics.

stop

public static void stop()

Stops the clearing of JMX metrics and restarting the Hadoop metrics system. This is needed for some test environments where we manually inject sources or sinks dynamically.

restart

public static void restart()

Restarts the stopped service.

See Also:

stop()