Package org.apache.hadoop.fs.statistics.impl

Class StubDurationTrackerFactory

java.lang.Object

org.apache.hadoop.fs.statistics.impl.StubDurationTrackerFactory

All Implemented Interfaces:

DurationTrackerFactory

public final class StubDurationTrackerFactory
extends Object
implements DurationTrackerFactory

This is a stub factory which always returns no-op duration trackers. Allows for code to always be handed a factory.

Field Summary

Fields

Modifier and Type	Field	Description
static final StubDurationTrackerFactory	STUB_DURATION_TRACKER_FACTORY	Single instance.

Method Summary

Modifier and Type	Method	Description
DurationTracker	trackDuration(String key, long count)	Initiate a duration tracking operation by creating/returning an object whose close() call will update the statistics.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.fs.statistics.DurationTrackerFactory

trackDuration

Field Details

STUB_DURATION_TRACKER_FACTORY

public static final StubDurationTrackerFactory STUB_DURATION_TRACKER_FACTORY

Single instance.

Method Details

trackDuration

public DurationTracker trackDuration(String key,
 long count)

Description copied from interface: DurationTrackerFactory

Initiate a duration tracking operation by creating/returning an object whose close() call will update the statistics. The statistics counter with the key name will be incremented by the given count. The expected use is within a try-with-resources clause. The default implementation returns a stub duration tracker.

Specified by:

trackDuration in interface DurationTrackerFactory

Parameters:

key - statistic key prefix

count - #of times to increment the matching counter in this operation.

Returns:

an object to close after an operation completes.