TimerGauge (Flink : Runtime 2.0.0 API)

java.lang.Object
- org.apache.flink.runtime.metrics.TimerGauge

All Implemented Interfaces:

org.apache.flink.metrics.Gauge<Long>, org.apache.flink.metrics.Metric, org.apache.flink.metrics.View
```
public class TimerGauge
extends Object
implements org.apache.flink.metrics.Gauge<Long>, org.apache.flink.metrics.View
```
TimerGauge measures how much time is spent in a given state, with entry into that state being signaled by markStart(). Measuring is stopped by markEnd(). This class in particularly takes care of the case, when update() is called when some measurement started but has not yet finished. For example even if next markEnd() call is expected to happen in a couple of hours, the returned value will account for this ongoing measurement.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static interface TimerGauge.StartStopListener
Listens for markStart() and markEnd() events.

Field Summary
- Fields inherited from interface org.apache.flink.metrics.View
  UPDATE_INTERVAL_SECONDS

Constructor Summary

Constructors
Constructor	Description
`TimerGauge()`
`TimerGauge(int timeSpanInSeconds)`
`TimerGauge(org.apache.flink.util.clock.Clock clock)`
`TimerGauge(org.apache.flink.util.clock.Clock clock, int timeSpanInSeconds)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`long`	`getAccumulatedCount()`
`long`	`getCount()`
`long`	`getMaxSingleMeasurement()`
`Long`	`getValue()`
`boolean`	`isMeasuring()`
`void`	`markEnd()`
`void`	`markStart()`
`void`	`registerListener(TimerGauge.StartStopListener listener)`
`void`	`unregisterListener(TimerGauge.StartStopListener listener)`
`void`	`update()`

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

Methods inherited from interface org.apache.flink.metrics.Gauge
getMetricType

Constructor Detail

TimerGauge
```
public TimerGauge()
```

TimerGauge

public TimerGauge(int timeSpanInSeconds)

TimerGauge

public TimerGauge(org.apache.flink.util.clock.Clock clock)

TimerGauge

public TimerGauge(org.apache.flink.util.clock.Clock clock,
                  int timeSpanInSeconds)

Method Detail
- registerListener
```
public void registerListener(TimerGauge.StartStopListener listener)
```
- unregisterListener
```
public void unregisterListener(TimerGauge.StartStopListener listener)
```
- markStart
```
public void markStart()
```
- markEnd
```
public void markEnd()
```
- update
```
public void update()
```
  Specified by:
  
  update in interface org.apache.flink.metrics.View
- getValue
```
public Long getValue()
```
  Specified by:
  
  getValue in interface org.apache.flink.metrics.Gauge<Long>
- getMaxSingleMeasurement
```
public long getMaxSingleMeasurement()
```
  Returns:
  
  the longest marked period as measured by the given * TimerGauge. For example the longest consecutive back pressured period.
- getAccumulatedCount
```
public long getAccumulatedCount()
```
  Returns:
  
  the accumulated period by the given * TimerGauge.
- getCount
```
@VisibleForTesting
public long getCount()
```
- isMeasuring
```
@VisibleForTesting
public boolean isMeasuring()
```