DynamicMetricsRegistry (Hortonworks Data Platform Apache HBase Java API Reference)

java.lang.Object
- org.apache.hadoop.metrics2.lib.DynamicMetricsRegistry

```
@InterfaceAudience.Private
public class DynamicMetricsRegistry
extends Object
```
An optional metrics registry class for creating and maintaining a collection of MetricsMutables, making writing metrics source easier. NOTE: this is a copy of org.apache.hadoop.metrics2.lib.MetricsRegistry with added one feature: metrics can be removed. When HADOOP-8313 is fixed, usages of this class should be substituted with org.apache.hadoop.metrics2.lib.MetricsRegistry. This implementation also provides handy methods for creating metrics dynamically. Another difference is that metricsMap implementation is substituted with thread-safe map, as we allow dynamic metrics additions/removals.

Constructor Summary

Constructors
Constructor and Description
`DynamicMetricsRegistry(MetricsInfo info)` Construct the registry with a metadata object
`DynamicMetricsRegistry(String name)` Construct the registry with a record name

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clearMetrics()`
`MutableMetric`	`get(String name)` Get a metric by name
`MutableHistogram`	`getHistogram(String histoName)`
`MutableCounterLong`	`getLongCounter(String counterName, long potentialStartingValue)` Get a MetricMutableCounterLong from the storage.
`MutableGaugeLong`	`getLongGauge(String gaugeName, long potentialStartingValue)` Get a MetricMutableGaugeLong from the storage.
`MetricMutableQuantiles`	`getQuantile(String histoName)`
`MetricsTag`	`getTag(String name)` Get a tag by name
`MetricsInfo`	`info()`
`MutableCounterInt`	`newCounter(MetricsInfo info, int iVal)` Create a mutable integer counter
`MutableCounterLong`	`newCounter(MetricsInfo info, long iVal)` Create a mutable long integer counter
`MutableCounterInt`	`newCounter(String name, String desc, int iVal)` Create a mutable integer counter
`MutableCounterLong`	`newCounter(String name, String desc, long iVal)` Create a mutable long integer counter
`MutableGaugeInt`	`newGauge(MetricsInfo info, int iVal)` Create a mutable integer gauge
`MutableGaugeLong`	`newGauge(MetricsInfo info, long iVal)` Create a mutable long integer gauge
`MutableGaugeInt`	`newGauge(String name, String desc, int iVal)` Create a mutable integer gauge
`MutableGaugeLong`	`newGauge(String name, String desc, long iVal)` Create a mutable long integer gauge
`MutableHistogram`	`newHistogram(String name)` Create a new histogram.
`MutableHistogram`	`newHistogram(String name, String desc)` Create a new histogram.
`MetricMutableQuantiles`	`newQuantile(String name)` Create a new MutableQuantile(A more accurate histogram).
`MetricMutableQuantiles`	`newQuantile(String name, String desc)`
`MutableRate`	`newRate(String name)` Create a mutable rate metric
`MutableRate`	`newRate(String name, String description)` Create a mutable rate metric
`MutableRate`	`newRate(String name, String desc, boolean extended)` Create a mutable rate metric (for throughput measurement)
`MutableRate`	`newRate(String name, String desc, boolean extended, boolean returnExisting)`
`MutableStat`	`newStat(String name, String desc, String sampleName, String valueName)` Create a mutable metric with stats
`MutableStat`	`newStat(String name, String desc, String sampleName, String valueName, boolean extended)` Create a mutable metric with stats
`void`	`removeMetric(String name)` Removes metric by name
`DynamicMetricsRegistry`	`setContext(String name)` Set the metrics context tag
`void`	`snapshot(MetricsRecordBuilder builder, boolean all)` Sample all the mutable metrics and put the snapshot in the builder
`DynamicMetricsRegistry`	`tag(MetricsInfo info, String value)`
`DynamicMetricsRegistry`	`tag(MetricsInfo info, String value, boolean override)` Add a tag to the metrics
`DynamicMetricsRegistry`	`tag(String name, String description, String value)` Add a tag to the metrics
`DynamicMetricsRegistry`	`tag(String name, String description, String value, boolean override)` Add a tag to the metrics
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail
- DynamicMetricsRegistry
```
public DynamicMetricsRegistry(String name)
```
  Construct the registry with a record name
  
  Parameters:
  
  name - of the record of the metrics
- DynamicMetricsRegistry
```
public DynamicMetricsRegistry(MetricsInfo info)
```
  Construct the registry with a metadata object
  
  Parameters:
  
  info - the info object for the metrics record/group

Method Detail

info
```
public MetricsInfo info()
```
Returns:

the info object of the metrics registry

get
```
public MutableMetric get(String name)
```
Get a metric by name

Parameters:

name - of the metric

Returns:

the metric object

getTag
```
public MetricsTag getTag(String name)
```
Get a tag by name

Parameters:

name - of the tag

Returns:

the tag object

newCounter

public MutableCounterInt newCounter(String name,
                                    String desc,
                                    int iVal)

Create a mutable integer counter

Parameters:: name - of the metric; desc - metric description; iVal - initial value
Returns:: a new counter object

newCounter
```
public MutableCounterInt newCounter(MetricsInfo info,
                                    int iVal)
```
Create a mutable integer counter

Parameters:

info - metadata of the metric

iVal - initial value

Returns:

a new counter object

newCounter

public MutableCounterLong newCounter(String name,
                                     String desc,
                                     long iVal)

Create a mutable long integer counter

Parameters:: name - of the metric; desc - metric description; iVal - initial value
Returns:: a new counter object

newCounter
```
public MutableCounterLong newCounter(MetricsInfo info,
                                     long iVal)
```
Create a mutable long integer counter

Parameters:

info - metadata of the metric

iVal - initial value

Returns:

a new counter object

newGauge

public MutableGaugeInt newGauge(String name,
                                String desc,
                                int iVal)

Create a mutable integer gauge

Parameters:: name - of the metric; desc - metric description; iVal - initial value
Returns:: a new gauge object

newGauge
```
public MutableGaugeInt newGauge(MetricsInfo info,
                                int iVal)
```
Create a mutable integer gauge

Parameters:

info - metadata of the metric

iVal - initial value

Returns:

a new gauge object

newGauge

public MutableGaugeLong newGauge(String name,
                                 String desc,
                                 long iVal)

Create a mutable long integer gauge

Parameters:: name - of the metric; desc - metric description; iVal - initial value
Returns:: a new gauge object

newGauge
```
public MutableGaugeLong newGauge(MetricsInfo info,
                                 long iVal)
```
Create a mutable long integer gauge

Parameters:

info - metadata of the metric

iVal - initial value

Returns:

a new gauge object

newStat

public MutableStat newStat(String name,
                           String desc,
                           String sampleName,
                           String valueName,
                           boolean extended)

Create a mutable metric with stats

Parameters:: name - of the metric; desc - metric description; sampleName - of the metric (e.g., "Ops"); valueName - of the metric (e.g., "Time" or "Latency"); extended - produce extended stat (stdev, min/max etc.) if true.
Returns:: a new mutable stat metric object

newStat

public MutableStat newStat(String name,
                           String desc,
                           String sampleName,
                           String valueName)

Create a mutable metric with stats

Parameters:: name - of the metric; desc - metric description; sampleName - of the metric (e.g., "Ops"); valueName - of the metric (e.g., "Time" or "Latency")
Returns:: a new mutable metric object

newRate
```
public MutableRate newRate(String name)
```
Create a mutable rate metric

Parameters:

name - of the metric

Returns:

a new mutable metric object

newRate
```
public MutableRate newRate(String name,
                           String description)
```
Create a mutable rate metric

Parameters:

name - of the metric

description - of the metric

Returns:

a new mutable rate metric object

newRate
```
public MutableRate newRate(String name,
                           String desc,
                           boolean extended)
```
Create a mutable rate metric (for throughput measurement)

Parameters:

name - of the metric

desc - description

extended - produce extended stat (stdev/min/max etc.) if true

Returns:

a new mutable rate metric object

newRate

@InterfaceAudience.Private
public MutableRate newRate(String name,
                                                      String desc,
                                                      boolean extended,
                                                      boolean returnExisting)

newHistogram
```
public MutableHistogram newHistogram(String name)
```
Create a new histogram.

Parameters:

name - Name of the histogram.

Returns:

A new MutableHistogram

newHistogram
```
public MutableHistogram newHistogram(String name,
                                     String desc)
```
Create a new histogram.

Parameters:

name - The name of the histogram

desc - The description of the data in the histogram.

Returns:

A new MutableHistogram

newQuantile
```
public MetricMutableQuantiles newQuantile(String name)
```
Create a new MutableQuantile(A more accurate histogram).

Parameters:

name - The name of the histogram

Returns:

a new MutableQuantile

newQuantile

public MetricMutableQuantiles newQuantile(String name,
                                          String desc)

setContext
```
public DynamicMetricsRegistry setContext(String name)
```
Set the metrics context tag

Parameters:

name - of the context

Returns:

the registry itself as a convenience

tag

public DynamicMetricsRegistry tag(String name,
                                  String description,
                                  String value)

Add a tag to the metrics

Parameters:: name - of the tag; description - of the tag; value - of the tag
Returns:: the registry (for keep adding tags)

tag

public DynamicMetricsRegistry tag(String name,
                                  String description,
                                  String value,
                                  boolean override)

Add a tag to the metrics

Parameters:: name - of the tag; description - of the tag; value - of the tag; override - existing tag if true
Returns:: the registry (for keep adding tags)

tag

public DynamicMetricsRegistry tag(MetricsInfo info,
                                  String value,
                                  boolean override)

Add a tag to the metrics

Parameters:: info - metadata of the tag; value - of the tag; override - existing tag if true
Returns:: the registry (for keep adding tags etc.)

tag

public DynamicMetricsRegistry tag(MetricsInfo info,
                                  String value)

snapshot
```
public void snapshot(MetricsRecordBuilder builder,
                     boolean all)
```
Sample all the mutable metrics and put the snapshot in the builder

Parameters:

builder - to contain the metrics snapshot

all - get all the metrics even if the values are not changed.

toString
```
public String toString()
```
Overrides:

toString in class Object

removeMetric
```
public void removeMetric(String name)
```
Removes metric by name

Parameters:

name - name of the metric to remove

getLongGauge
```
public MutableGaugeLong getLongGauge(String gaugeName,
                                     long potentialStartingValue)
```
Get a MetricMutableGaugeLong from the storage. If it is not there atomically put it.

Parameters:

gaugeName - name of the gauge to create or get.

potentialStartingValue - value of the new gauge if we have to create it.

getLongCounter
```
public MutableCounterLong getLongCounter(String counterName,
                                         long potentialStartingValue)
```
Get a MetricMutableCounterLong from the storage. If it is not there atomically put it.

Parameters:

counterName - Name of the counter to get

potentialStartingValue - starting value if we have to create a new counter

getHistogram

public MutableHistogram getHistogram(String histoName)

getQuantile

public MetricMutableQuantiles getQuantile(String histoName)

clearMetrics
```
public void clearMetrics()
```

Class DynamicMetricsRegistry

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

DynamicMetricsRegistry

DynamicMetricsRegistry

Method Detail

info

get

getTag

newCounter

newCounter

newCounter

newCounter

newGauge

newGauge

newGauge

newGauge

newStat

newStat

newRate

newRate

newRate

newRate

newHistogram

newHistogram

newQuantile

newQuantile

setContext

tag

tag

tag

tag

snapshot

toString

removeMetric

getLongGauge

getLongCounter

getHistogram

getQuantile

clearMetrics