org.apache.kafka.common

Class MetricName

java.lang.Object

org.apache.kafka.common.MetricName

public final class MetricName
extends java.lang.Object

The MetricName class encapsulates a metric's name, logical group and its related attributes. It should be constructed using metrics.MetricName(...).

This class captures the following parameters:

  name The name of the metric
  group logical group name of the metrics to which this metric belongs.
  description A human-readable description to include in the metric. This is optional.
  tags additional key/value attributes of the metric. This is optional.
 

group, tags parameters can be used to create unique metric names while reporting in JMX or any custom reporting.

Ex: standard JMX MBean can be constructed like domainName:type=group,key1=val1,key2=val2

Usage looks something like this:

 // set up metrics:

 Map<String, String> metricTags = new LinkedHashMap<String, String>();
 metricTags.put("client-id", "producer-1");
 metricTags.put("topic", "topic");

 MetricConfig metricConfig = new MetricConfig().tags(metricTags);
 Metrics metrics = new Metrics(metricConfig); // this is the global repository of metrics and sensors

 Sensor sensor = metrics.sensor("message-sizes");

 MetricName metricName = metrics.metricName("message-size-avg", "producer-metrics", "average message size");
 sensor.add(metricName, new Avg());

 metricName = metrics.metricName("message-size-max", "producer-metrics");
 sensor.add(metricName, new Max());

 metricName = metrics.metricName("message-size-min", "producer-metrics", "message minimum size", "client-id", "my-client", "topic", "my-topic");
 sensor.add(metricName, new Min());

 // as messages are sent we record the sizes
 sensor.record(messageSize);
 

Constructor Summary

Constructors

Constructor and Description
MetricName(java.lang.String name, java.lang.String group, java.lang.String description, java.util.Map<java.lang.String,java.lang.String> tags) Please create MetricName by method Metrics.metricName(String, String, String, Map)

Method Summary

Modifier and Type	Method and Description
java.lang.String	description()
boolean	equals(java.lang.Object obj)
java.lang.String	group()
int	hashCode()
java.lang.String	name()
java.util.Map<java.lang.String,java.lang.String>	tags()
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

MetricName

public MetricName(java.lang.String name,
                  java.lang.String group,
                  java.lang.String description,
                  java.util.Map<java.lang.String,java.lang.String> tags)

Please create MetricName by method Metrics.metricName(String, String, String, Map)

Parameters:

name - The name of the metric

group - logical group name of the metrics to which this metric belongs

description - A human-readable description to include in the metric

tags - additional key/value attributes of the metric

Method Detail

name

public java.lang.String name()

group

public java.lang.String group()

tags

public java.util.Map<java.lang.String,java.lang.String> tags()

description

public java.lang.String description()

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object