org.apache.solr.util.stats

Class MetricUtils

java.lang.Object

org.apache.solr.util.stats.MetricUtils

public class MetricUtils
extends Object

Metrics specific utility functions.

Field Summary

Fields

Modifier and Type	Field and Description
static String[]	OS_MXBEAN_CLASSES These are well-known implementations of OperatingSystemMXBean.
static String	VALUE

Constructor Summary

Constructors

Constructor and Description
MetricUtils()

Method Summary

Modifier and Type	Method and Description
static void	addMetrics(NamedList<Object> lst, com.codahale.metrics.Timer timer) Adds metrics from a Timer to a NamedList, using well-known back-compat names.
static <T extends PlatformManagedObject> void	addMXBeanMetrics(T obj, Class<? extends T> intf, String prefix, BiConsumer<String,com.codahale.metrics.Metric> consumer) Creates a set of metrics (gauges) that correspond to available bean properties for the provided MXBean.
static <T extends PlatformManagedObject> void	addMXBeanMetrics(T obj, String[] interfaces, String prefix, BiConsumer<String,com.codahale.metrics.Metric> consumer) Creates a set of metrics (gauges) that correspond to available bean properties for the provided MXBean.
static ExecutorService	instrumentedExecutorService(ExecutorService delegate, com.codahale.metrics.MetricRegistry metricRegistry, String scope) Returns an instrumented wrapper over the given executor service.
static double	nsToMs(double ns) Converts a double representing nanoseconds to a double representing milliseconds.
static void	toMaps(com.codahale.metrics.MetricRegistry registry, List<com.codahale.metrics.MetricFilter> shouldMatchFilters, com.codahale.metrics.MetricFilter mustMatchFilter, boolean skipHistograms, boolean skipAggregateValues, boolean compact, BiConsumer<String,Object> consumer)
static NamedList	toNamedList(com.codahale.metrics.MetricRegistry registry, List<com.codahale.metrics.MetricFilter> shouldMatchFilters, com.codahale.metrics.MetricFilter mustMatchFilter, boolean skipHistograms, boolean skipAggregateValues, boolean compact, Map<String,Object> metadata) Returns a NamedList representation of the given metric registry.

Methods inherited from class java.lang.Object

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

Field Detail

VALUE

public static final String VALUE

See Also:

Constant Field Values

OS_MXBEAN_CLASSES

public static String[] OS_MXBEAN_CLASSES

These are well-known implementations of OperatingSystemMXBean. Some of them provide additional useful properties beyond those declared by the interface.

Constructor Detail

MetricUtils

public MetricUtils()

Method Detail

addMetrics

public static void addMetrics(NamedList<Object> lst,
                              com.codahale.metrics.Timer timer)

Adds metrics from a Timer to a NamedList, using well-known back-compat names.

Parameters:

lst - The NamedList to add the metrics data to

timer - The Timer to extract the metrics from

nsToMs

public static double nsToMs(double ns)

Converts a double representing nanoseconds to a double representing milliseconds.

Parameters:

ns - the amount of time in nanoseconds

Returns:

the amount of time in milliseconds

toNamedList

public static NamedList toNamedList(com.codahale.metrics.MetricRegistry registry,
                                    List<com.codahale.metrics.MetricFilter> shouldMatchFilters,
                                    com.codahale.metrics.MetricFilter mustMatchFilter,
                                    boolean skipHistograms,
                                    boolean skipAggregateValues,
                                    boolean compact,
                                    Map<String,Object> metadata)

Returns a NamedList representation of the given metric registry. Only those metrics are converted to NamedList which match at least one of the given MetricFilter instances.

Parameters:

registry - the MetricRegistry to be converted to NamedList

shouldMatchFilters - a list of MetricFilter instances. A metric must match any one of the filters from this list to be included in the output

mustMatchFilter - a MetricFilter. A metric must match this filter to be included in the output.

skipHistograms - discard any Histogram-s and histogram parts of Timer-s.

compact - use compact representation for counters and gauges.

metadata - optional metadata. If not null and not empty then this map will be added under a _metadata_ key.

Returns:

a NamedList

toMaps

public static void toMaps(com.codahale.metrics.MetricRegistry registry,
                          List<com.codahale.metrics.MetricFilter> shouldMatchFilters,
                          com.codahale.metrics.MetricFilter mustMatchFilter,
                          boolean skipHistograms,
                          boolean skipAggregateValues,
                          boolean compact,
                          BiConsumer<String,Object> consumer)

instrumentedExecutorService

public static ExecutorService instrumentedExecutorService(ExecutorService delegate,
                                                          com.codahale.metrics.MetricRegistry metricRegistry,
                                                          String scope)

Returns an instrumented wrapper over the given executor service.

addMXBeanMetrics

public static <T extends PlatformManagedObject> void addMXBeanMetrics(T obj,
                                                                      Class<? extends T> intf,
                                                                      String prefix,
                                                                      BiConsumer<String,com.codahale.metrics.Metric> consumer)

Creates a set of metrics (gauges) that correspond to available bean properties for the provided MXBean.

Type Parameters:

T - formal type

Parameters:

obj - an instance of MXBean

intf - MXBean interface, one of PlatformManagedObject-s

consumer - consumer for created names and metrics

addMXBeanMetrics

public static <T extends PlatformManagedObject> void addMXBeanMetrics(T obj,
                                                                      String[] interfaces,
                                                                      String prefix,
                                                                      BiConsumer<String,com.codahale.metrics.Metric> consumer)

Creates a set of metrics (gauges) that correspond to available bean properties for the provided MXBean.

Type Parameters:

T - formal type

Parameters:

obj - an instance of MXBean

interfaces - interfaces that it may implement. Each interface will be tried in turn, and only if it exists and if it contains unique properties then they will be added as metrics.

prefix - optional prefix for metric names

consumer - consumer for created names and metrics