Package org.apache.kafka.common.metrics

Class Sensor

java.lang.Object

org.apache.kafka.common.metrics.Sensor

public final class Sensor
extends Object

A sensor applies a continuous sequence of numerical values to a set of associated metrics. For example a sensor on message size would record a sequence of message sizes using the record(double) api and would maintain a set of metrics about request sizes such as the average or max.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Sensor.RecordingLevel

Method Summary

Modifier and Type	Method	Description
boolean	add(MetricName metricName, MeasurableStat stat)	Register a metric with this sensor
boolean	add(MetricName metricName, MeasurableStat stat, MetricConfig config)	Register a metric with this sensor
boolean	add(CompoundStat stat)	Register a compound statistic with this sensor with no config override
boolean	add(CompoundStat stat, MetricConfig config)	Register a compound statistic with this sensor which yields multiple measurable quantities (like a histogram)
void	checkQuotas()	Check if we have violated our quota for any metric that has a configured quota
void	checkQuotas(long timeMs)
boolean	hasExpired()	Return true if the Sensor is eligible for removal due to inactivity.
boolean	hasMetrics()	Return if metrics were registered with this sensor.
String	name()	The name this sensor is registered with.
void	record()	Record an occurrence, this is just short-hand for record(1.0)
void	record(double value)	Record a value with this sensor
void	record(double value, long timeMs)	Record a value at a known time.
void	record(double value, long timeMs, boolean checkQuotas)	Record a value at a known time.
boolean	shouldRecord()

Methods inherited from class java.lang.Object

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

Method Detail

name

public String name()

The name this sensor is registered with. This name will be unique among all registered sensors.

shouldRecord

public boolean shouldRecord()

Returns:

true if the sensor's record level indicates that the metric will be recorded, false otherwise

record

public void record()

Record an occurrence, this is just short-hand for record(1.0)

record

public void record(double value)

Record a value with this sensor

Parameters:

value - The value to record

Throws:

QuotaViolationException - if recording this value moves a metric beyond its configured maximum or minimum bound

record

public void record(double value,
                   long timeMs)

Record a value at a known time. This method is slightly faster than record(double) since it will reuse the time stamp.

Parameters:

value - The value we are recording

timeMs - The current POSIX time in milliseconds

Throws:

QuotaViolationException - if recording this value moves a metric beyond its configured maximum or minimum bound

record

public void record(double value,
                   long timeMs,
                   boolean checkQuotas)

Record a value at a known time. This method is slightly faster than record(double) since it will reuse the time stamp.

Parameters:

value - The value we are recording

timeMs - The current POSIX time in milliseconds

checkQuotas - Indicate if quota must be enforced or not

Throws:

QuotaViolationException - if recording this value moves a metric beyond its configured maximum or minimum bound

checkQuotas

public void checkQuotas()

Check if we have violated our quota for any metric that has a configured quota

checkQuotas

public void checkQuotas(long timeMs)

add

public boolean add(CompoundStat stat)

Register a compound statistic with this sensor with no config override

Parameters:

stat - The stat to register

Returns:

true if stat is added to sensor, false if sensor is expired

add

public boolean add(CompoundStat stat,
                   MetricConfig config)

Register a compound statistic with this sensor which yields multiple measurable quantities (like a histogram)

Parameters:

stat - The stat to register

config - The configuration for this stat. If null then the stat will use the default configuration for this sensor.

Returns:

true if stat is added to sensor, false if sensor is expired

add

public boolean add(MetricName metricName,
                   MeasurableStat stat)

Register a metric with this sensor

Parameters:

metricName - The name of the metric

stat - The statistic to keep

Returns:

true if metric is added to sensor, false if sensor is expired

add

public boolean add(MetricName metricName,
                   MeasurableStat stat,
                   MetricConfig config)

Register a metric with this sensor

Parameters:

metricName - The name of the metric

stat - The statistic to keep

config - A special configuration for this metric. If null use the sensor default configuration.

Returns:

true if metric is added to sensor, false if sensor is expired

hasMetrics

public boolean hasMetrics()

Return if metrics were registered with this sensor.

Returns:

true if metrics were registered, false otherwise

hasExpired

public boolean hasExpired()

Return true if the Sensor is eligible for removal due to inactivity. false otherwise