org.apache.bookkeeper.stats

Class NullStatsLogger

java.lang.Object

org.apache.bookkeeper.stats.NullStatsLogger

All Implemented Interfaces:

StatsLogger

public class NullStatsLogger
extends java.lang.Object
implements StatsLogger

A no-op StatsLogger.

Metrics are not recorded, making this receiver useful in unit tests and as defaults in situations where metrics are not strictly required.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	NullStatsLogger.NullCounter A no-op Counter.
(package private) static class	NullStatsLogger.NullOpStatsLogger A no-op OpStatsLogger.

Field Summary

Fields

Modifier and Type	Field and Description
static NullStatsLogger	INSTANCE
(package private) static NullStatsLogger.NullCounter	nullCounter
(package private) static NullStatsLogger.NullOpStatsLogger	nullOpStatsLogger

Constructor Summary

Constructors

Constructor and Description
NullStatsLogger()

Method Summary

Modifier and Type	Method and Description
Counter	getCounter(java.lang.String name)
OpStatsLogger	getOpStatsLogger(java.lang.String name)
<T extends java.lang.Number> void	registerGauge(java.lang.String name, Gauge<T> gauge) Register given gauge as name name.
void	removeScope(java.lang.String name, StatsLogger statsLogger) Remove the given statsLogger for scope name.
StatsLogger	scope(java.lang.String name) Provide the stats logger under scope name.
<T extends java.lang.Number> void	unregisterGauge(java.lang.String name, Gauge<T> gauge) Unregister given gauge from name name.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.bookkeeper.stats.StatsLogger

scopeLabel

Field Detail

INSTANCE

public static final NullStatsLogger INSTANCE

nullOpStatsLogger

static NullStatsLogger.NullOpStatsLogger nullOpStatsLogger

nullCounter

static NullStatsLogger.NullCounter nullCounter

Constructor Detail

NullStatsLogger

public NullStatsLogger()

Method Detail

getOpStatsLogger

public OpStatsLogger getOpStatsLogger(java.lang.String name)

Specified by:

getOpStatsLogger in interface StatsLogger

Parameters:

name - Stats Name

Returns:

Get the logger for an OpStat described by the name.

getCounter

public Counter getCounter(java.lang.String name)

Specified by:

getCounter in interface StatsLogger

Parameters:

name - Stats Name

Returns:

Get the logger for a simple stat described by the name

registerGauge

public <T extends java.lang.Number> void registerGauge(java.lang.String name,
                                                       Gauge<T> gauge)

Description copied from interface: StatsLogger

Register given gauge as name name.

Specified by:

registerGauge in interface StatsLogger

Parameters:

name - gauge name

gauge - gauge function

unregisterGauge

public <T extends java.lang.Number> void unregisterGauge(java.lang.String name,
                                                         Gauge<T> gauge)

Description copied from interface: StatsLogger

Unregister given gauge from name name.

Specified by:

unregisterGauge in interface StatsLogger

Parameters:

name - name of the gauge

gauge - gauge function

scope

public StatsLogger scope(java.lang.String name)

Description copied from interface: StatsLogger

Provide the stats logger under scope name.

Specified by:

scope in interface StatsLogger

Parameters:

name - scope name.

Returns:

stats logger under scope name.

removeScope

public void removeScope(java.lang.String name,
                        StatsLogger statsLogger)

Description copied from interface: StatsLogger

Remove the given statsLogger for scope name. It can be no-op if the underlying stats provider doesn't have the ability to remove scope.

Specified by:

removeScope in interface StatsLogger

Parameters:

name - name of the scope

statsLogger - the stats logger of this scope.