org.apache.hadoop.metrics2.lib
Class MetricsRegistry

java.lang.Object
  org.apache.hadoop.metrics2.lib.MetricsRegistry

public class MetricsRegistry
extends Object

An optional metrics registry class for creating and maintaining a collection of MetricsMutables, making writing metrics source easier.

Field Summary

static String	CONTEXT_DESC description for the context tag
static String	CONTEXT_KEY key for the context tag

Constructor Summary

MetricsRegistry(String name)
Construct the registry with a record name

MetricsRegistry(String name, MetricMutableFactory factory)
Construct the registry with a name and a metric factory

Method Summary

void	add(String name, long value) Add a value to a metric by name.
void	add(String name, long value, MetricMutableFactory factory) Decrement a metric by name.
void	decr(String name) Decrement a metric by name.
void	decr(String name, MetricMutableFactory factory) Decrement a metric by name.
MetricMutable	get(String name) Get a metric by name
void	incr(String name) Increment a metric by name.
void	incr(String name, MetricMutableFactory factory) Increment a metric by name.
Set<Map.Entry<String,MetricMutable>>	metrics() Get the metrics
String	name()
MetricMutableCounterInt	newCounter(String name, String description, int initValue) Create a mutable integer counter
MetricMutableCounterLong	newCounter(String name, String description, long initValue) Create a mutable long integer counter
MetricMutableGaugeInt	newGauge(String name, String description, int initValue) Create a mutable integer gauge
MetricMutableGaugeLong	newGauge(String name, String description, long initValue) Create a mutable long integer gauge
MetricMutableStat	newStat(String name) Create a mutable metric with stats using the name only
MetricMutableStat	newStat(String name, String description, String sampleName, String valueName) Create a mutable metric with stats
MetricMutableStat	newStat(String name, String description, String sampleName, String valueName, boolean extended) Create a mutable metric with stats
MetricsRegistry	setContext(String name) Set the metrics context tag
void	snapshot(MetricsRecordBuilder builder, boolean all) Sample all the mutable metrics and put the snapshot in the builder
MetricsRegistry	tag(String name, String description, String value) Add a tag to the metrics
MetricsRegistry	tag(String name, String description, String value, boolean override) Add a tag to the metrics
Set<Map.Entry<String,MetricsTag>>	tags() Get the tags

Methods inherited from class java.lang.Object

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

Field Detail

CONTEXT_KEY

public static final String CONTEXT_KEY

key for the context tag

See Also:

Constant Field Values

CONTEXT_DESC

public static final String CONTEXT_DESC

description for the context tag

See Also:

Constant Field Values

Constructor Detail

MetricsRegistry

public MetricsRegistry(String name)

Construct the registry with a record name

Parameters:

name - of the record of the metrics

MetricsRegistry

public MetricsRegistry(String name,
                       MetricMutableFactory factory)

Construct the registry with a name and a metric factory

Parameters:

name - of the record of the metrics

factory - for creating new mutable metrics

Method Detail

name

public String name()

Returns:

the name of the metrics registry

get

public MetricMutable get(String name)

Get a metric by name

Parameters:

name - of the metric

Returns:

the metric object

newCounter

public MetricMutableCounterInt newCounter(String name,
                                          String description,
                                          int initValue)

Create a mutable integer counter

Parameters:

name - of the metric

description - of the metric

initValue - of the metric

Returns:

a new counter object

newCounter

public MetricMutableCounterLong newCounter(String name,
                                           String description,
                                           long initValue)

Create a mutable long integer counter

Parameters:

name - of the metric

description - of the metric

initValue - of the metric

Returns:

a new counter object

newGauge

public MetricMutableGaugeInt newGauge(String name,
                                      String description,
                                      int initValue)

Create a mutable integer gauge

Parameters:

name - of the metric

description - of the metric

initValue - of the metric

Returns:

a new gauge object

newGauge

public MetricMutableGaugeLong newGauge(String name,
                                       String description,
                                       long initValue)

Create a mutable long integer gauge

Parameters:

name - of the metric

description - of the metric

initValue - of the metric

Returns:

a new gauge object

newStat

public MetricMutableStat newStat(String name,
                                 String description,
                                 String sampleName,
                                 String valueName,
                                 boolean extended)

Create a mutable metric with stats

Parameters:

name - of the metric

description - of the metric

sampleName - of the metric (e.g., "ops")

valueName - of the metric (e.g., "time" or "latency")

extended - produce extended stat (stdev, min/max etc.) if true.

Returns:

a new metric object

newStat

public MetricMutableStat newStat(String name,
                                 String description,
                                 String sampleName,
                                 String valueName)

Create a mutable metric with stats

Parameters:

name - of the metric

description - of the metric

sampleName - of the metric (e.g., "ops")

valueName - of the metric (e.g., "time" or "latency")

Returns:

a new metric object

newStat

public MetricMutableStat newStat(String name)

Create a mutable metric with stats using the name only

Parameters:

name - of the metric

Returns:

a new metric object

incr

public void incr(String name)

Increment a metric by name.

Parameters:

name - of the metric

incr

public void incr(String name,
                 MetricMutableFactory factory)

Increment a metric by name.

Parameters:

name - of the metric

factory - to lazily create the metric if not null

decr

public void decr(String name)

Decrement a metric by name.

Parameters:

name - of the metric

decr

public void decr(String name,
                 MetricMutableFactory factory)

Decrement a metric by name.

Parameters:

name - of the metric

factory - to lazily create the metric if not null

add

public void add(String name,
                long value)

Add a value to a metric by name.

Parameters:

name - of the metric

value - of the snapshot to add

add

public void add(String name,
                long value,
                MetricMutableFactory factory)

Decrement a metric by name.

Parameters:

name - of the metric

value - of the snapshot to add

factory - to lazily create the metric if not null

setContext

public MetricsRegistry setContext(String name)

Set the metrics context tag

Parameters:

name - of the context

Returns:

the registry itself as a convenience

tag

public MetricsRegistry tag(String name,
                           String description,
                           String value)

Add a tag to the metrics

Parameters:

name - of the tag

description - of the tag

value - of the tag

Returns:

the registry (for keep adding tags)

tag

public MetricsRegistry tag(String name,
                           String description,
                           String value,
                           boolean override)

Add a tag to the metrics

Parameters:

name - of the tag

description - of the tag

value - of the tag

override - existing tag if true

Returns:

the registry (for keep adding tags)

tags

public Set<Map.Entry<String,MetricsTag>> tags()

Get the tags

Returns:

the tags set

metrics

public Set<Map.Entry<String,MetricMutable>> metrics()

Get the metrics

Returns:

the metrics set

snapshot

public void snapshot(MetricsRecordBuilder builder,
                     boolean all)

Sample all the mutable metrics and put the snapshot in the builder

Parameters:

builder - to contain the metrics snapshot

all - get all the metrics even if the values are not changed.