org.apache.oozie.util

Class MetricsInstrumentation

java.lang.Object

org.apache.oozie.util.Instrumentation

org.apache.oozie.util.MetricsInstrumentation

public class MetricsInstrumentation
extends Instrumentation

Instrumentation framework that is mostly compatible with Instrumentation but is backed by Codahale Metrics. This class was designed to minimize the changes required to switch from Instrumentation to MetricsInstrumentation by keeping the same API. However, certain operations are obviously implemented differently or are no longer needed; and the output format is a little different. Internally, this class maps Cron to Timer, Variable to Gauge, counter to Counter, and Sampler to Histogram.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MetricsInstrumentation.Sampler

Nested classes/interfaces inherited from class org.apache.oozie.util.Instrumentation

Instrumentation.Cron, Instrumentation.Element<T>, Instrumentation.Timer, Instrumentation.Variable<T>

Constructor Summary

Constructors

Constructor and Description
MetricsInstrumentation() Creates the MetricsInstrumentation and starts taking some metrics.

Method Summary

Methods

Modifier and Type	Method and Description
void	addCron(String group, String name, Instrumentation.Cron cron) Add a cron to an instrumentation timer.
void	addSampler(String group, String name, int period, int interval, Instrumentation.Variable<Long> variable) Add a sampling variable.
void	addVariable(String group, String name, Instrumentation.Variable variable) Add an instrumentation variable.
Map<String,Map<String,Map<String,Object>>>	getAll() Not Supported: throws UnsupportedOperationException
Map<String,Map<String,Instrumentation.Element<Long>>>	getCounters() Not Supported: throws UnsupportedOperationException
Map<String,Map<String,Instrumentation.Element<Double>>>	getSamplers() Not Supported: throws UnsupportedOperationException
Map<String,Map<String,Instrumentation.Element<Instrumentation.Timer>>>	getTimers() Not Supported: throws UnsupportedOperationException
Map<String,Map<String,Instrumentation.Element<Instrumentation.Variable>>>	getVariables() Not Supported: throws UnsupportedOperationException
void	incr(String group, String name, long count) Increment an instrumentation counter.
void	setScheduler(ScheduledExecutorService scheduler) Set the scheduler instance to handle the samplers.
String	toString() Return the string representation of the instrumentation.
void	writeJSONResponse(OutputStream os) Converts the current state of the metrics and writes them to the OutputStream.

Methods inherited from class org.apache.oozie.util.Instrumentation

getConfiguration, getJavaSystemProperties, getOSEnv

Methods inherited from class java.lang.Object

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

Constructor Detail

MetricsInstrumentation

public MetricsInstrumentation()

Creates the MetricsInstrumentation and starts taking some metrics.

Method Detail

addCron

public void addCron(String group,
           String name,
           Instrumentation.Cron cron)

Add a cron to an instrumentation timer. The timer is created if it does not exists.

Internally, this is backed by a Timer.

Overrides:

addCron in class Instrumentation

Parameters:

group - timer group.

name - timer name.

cron - cron to add to the timer.

addVariable

public void addVariable(String group,
               String name,
               Instrumentation.Variable variable)

Add an instrumentation variable.

Internally, this is backed by a Gauge.

Overrides:

addVariable in class Instrumentation

Parameters:

group - counter group.

name - counter name.

variable - variable to add.

incr

public void incr(String group,
        String name,
        long count)

Increment an instrumentation counter. The counter is created if it does not exists.

Internally, this is backed by a Counter.

Overrides:

incr in class Instrumentation

Parameters:

group - counter group.

name - counter name.

count - increment to add to the counter.

addSampler

public void addSampler(String group,
              String name,
              int period,
              int interval,
              Instrumentation.Variable<Long> variable)

Add a sampling variable.

Internally, this is backed by a biased (decaying) Histogram.

Overrides:

addSampler in class Instrumentation

Parameters:

group - timer group.

name - timer name.

period - (ignored)

interval - sampling frequency, how often the variable is probed.

variable - variable to sample.

setScheduler

public void setScheduler(ScheduledExecutorService scheduler)

Set the scheduler instance to handle the samplers.

Overrides:

setScheduler in class Instrumentation

Parameters:

scheduler - scheduler instance.

toString

public String toString()

Return the string representation of the instrumentation. It does a JSON pretty-print.

Overrides:

toString in class Instrumentation

Returns:

the string representation of the instrumentation.

writeJSONResponse

public void writeJSONResponse(OutputStream os)
                       throws IOException

Converts the current state of the metrics and writes them to the OutputStream.

Parameters:

os - The OutputStream to write the metrics to

Throws:

IOException

getAll

public Map<String,Map<String,Map<String,Object>>> getAll()

Not Supported: throws UnsupportedOperationException

Overrides:

getAll in class Instrumentation

Returns:

nothing

getCounters

public Map<String,Map<String,Instrumentation.Element<Long>>> getCounters()

Not Supported: throws UnsupportedOperationException

Overrides:

getCounters in class Instrumentation

Returns:

nothing

getSamplers

public Map<String,Map<String,Instrumentation.Element<Double>>> getSamplers()

Not Supported: throws UnsupportedOperationException

Overrides:

getSamplers in class Instrumentation

Returns:

nothing

getTimers

public Map<String,Map<String,Instrumentation.Element<Instrumentation.Timer>>> getTimers()

Not Supported: throws UnsupportedOperationException

Overrides:

getTimers in class Instrumentation

Returns:

nothing

getVariables

public Map<String,Map<String,Instrumentation.Element<Instrumentation.Variable>>> getVariables()

Not Supported: throws UnsupportedOperationException

Overrides:

getVariables in class Instrumentation

Returns:

nothing