org.apache.flink.runtime.metrics.groups

Class AbstractMetricGroup

java.lang.Object

org.apache.flink.runtime.metrics.groups.AbstractMetricGroup

All Implemented Interfaces:

org.apache.flink.metrics.MetricGroup

Direct Known Subclasses:

ComponentMetricGroup, GenericMetricGroup

public abstract class AbstractMetricGroup
extends Object
implements org.apache.flink.metrics.MetricGroup

Abstract MetricGroup that contains key functionality for adding metrics and groups.

IMPORTANT IMPLEMENTATION NOTE

This class uses locks for adding and removing metrics objects. This is done to prevent resource leaks in the presence of concurrently closing a group and adding metrics and subgroups. Since closing groups recursively closes the subgroups, the lock acquisition order must be strictly from parent group to subgroup. If at any point, a subgroup holds its group lock and calls a parent method that also acquires the lock, it will create a deadlock condition.

An AbstractMetricGroup can be closed. Upon closing, the group de-register all metrics from any metrics reporter and any internal maps. Note that even closed metrics groups return Counters, Gauges, etc to the code, to prevent exceptions in the monitored code. These metrics simply do not get reported any more, when created on a closed group.

Field Summary

Fields

Modifier and Type	Field and Description
protected MetricRegistry	registry The registry that this metrics group belongs to

Constructor Summary

Constructors

Constructor and Description
AbstractMetricGroup(MetricRegistry registry, String[] scope)

Method Summary

Modifier and Type	Method and Description
org.apache.flink.metrics.MetricGroup	addGroup(int name)
org.apache.flink.metrics.MetricGroup	addGroup(String name)
protected void	addMetric(String name, org.apache.flink.metrics.Metric metric) Adds the given metric to the group and registers it at the registry, if the group is not yet closed, and if no metric with the same name has been registered before.
void	close()
org.apache.flink.metrics.Counter	counter(int name)
<C extends org.apache.flink.metrics.Counter> C	counter(int name, C counter)
org.apache.flink.metrics.Counter	counter(String name)
<C extends org.apache.flink.metrics.Counter> C	counter(String name, C counter)
<T,G extends org.apache.flink.metrics.Gauge<T>> G	gauge(int name, G gauge)
<T,G extends org.apache.flink.metrics.Gauge<T>> G	gauge(String name, G gauge)
String	getMetricIdentifier(String metricName) Returns the fully qualified metric name, for example "host-7.taskmanager-2.window_word_count.my-mapper.metricName"
String	getMetricIdentifier(String metricName, org.apache.flink.metrics.CharacterFilter filter) Returns the fully qualified metric name, for example "host-7.taskmanager-2.window_word_count.my-mapper.metricName"
String[]	getScopeComponents() Gets the scope as an array of the scope components, for example ["host-7", "taskmanager-2", "window_word_count", "my-mapper"]
<H extends org.apache.flink.metrics.Histogram> H	histogram(int name, H histogram)
<H extends org.apache.flink.metrics.Histogram> H	histogram(String name, H histogram)
boolean	isClosed()

Methods inherited from class java.lang.Object

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

Field Detail

registry

protected final MetricRegistry registry

The registry that this metrics group belongs to

Constructor Detail

AbstractMetricGroup

public AbstractMetricGroup(MetricRegistry registry,
                           String[] scope)

Method Detail

getScopeComponents

public String[] getScopeComponents()

Gets the scope as an array of the scope components, for example ["host-7", "taskmanager-2", "window_word_count", "my-mapper"]

Specified by:

getScopeComponents in interface org.apache.flink.metrics.MetricGroup

See Also:

getMetricIdentifier(String)

getMetricIdentifier

public String getMetricIdentifier(String metricName)

Returns the fully qualified metric name, for example "host-7.taskmanager-2.window_word_count.my-mapper.metricName"

Specified by:

getMetricIdentifier in interface org.apache.flink.metrics.MetricGroup

Parameters:

metricName - metric name

Returns:

fully qualified metric name

getMetricIdentifier

public String getMetricIdentifier(String metricName,
                                  org.apache.flink.metrics.CharacterFilter filter)

Returns the fully qualified metric name, for example "host-7.taskmanager-2.window_word_count.my-mapper.metricName"

Specified by:

getMetricIdentifier in interface org.apache.flink.metrics.MetricGroup

Parameters:

metricName - metric name

filter - character filter which is applied to the scope components if not null.

Returns:

fully qualified metric name

close

public void close()

isClosed

public final boolean isClosed()

counter

public org.apache.flink.metrics.Counter counter(int name)

Specified by:

counter in interface org.apache.flink.metrics.MetricGroup

counter

public org.apache.flink.metrics.Counter counter(String name)

Specified by:

counter in interface org.apache.flink.metrics.MetricGroup

counter

public <C extends org.apache.flink.metrics.Counter> C counter(int name,
                                                              C counter)

Specified by:

counter in interface org.apache.flink.metrics.MetricGroup

counter

public <C extends org.apache.flink.metrics.Counter> C counter(String name,
                                                              C counter)

Specified by:

counter in interface org.apache.flink.metrics.MetricGroup

gauge

public <T,G extends org.apache.flink.metrics.Gauge<T>> G gauge(int name,
                                                               G gauge)

Specified by:

gauge in interface org.apache.flink.metrics.MetricGroup

gauge

public <T,G extends org.apache.flink.metrics.Gauge<T>> G gauge(String name,
                                                               G gauge)

Specified by:

gauge in interface org.apache.flink.metrics.MetricGroup

histogram

public <H extends org.apache.flink.metrics.Histogram> H histogram(int name,
                                                                  H histogram)

Specified by:

histogram in interface org.apache.flink.metrics.MetricGroup

histogram

public <H extends org.apache.flink.metrics.Histogram> H histogram(String name,
                                                                  H histogram)

Specified by:

histogram in interface org.apache.flink.metrics.MetricGroup

addMetric

protected void addMetric(String name,
                         org.apache.flink.metrics.Metric metric)

Adds the given metric to the group and registers it at the registry, if the group is not yet closed, and if no metric with the same name has been registered before.

Parameters:

name - the name to register the metric under

metric - the metric to register

addGroup

public org.apache.flink.metrics.MetricGroup addGroup(int name)

Specified by:

addGroup in interface org.apache.flink.metrics.MetricGroup

addGroup

public org.apache.flink.metrics.MetricGroup addGroup(String name)

Specified by:

addGroup in interface org.apache.flink.metrics.MetricGroup