Package org.apache.hadoop.fs

Class StorageStatistics

java.lang.Object

org.apache.hadoop.fs.StorageStatistics

Direct Known Subclasses:

FileSystemStorageStatistics, StorageStatisticsFromIOStatistics, UnionStorageStatistics

@Public
@Stable
public abstract class StorageStatistics
extends Object

StorageStatistics contains statistics data for a FileSystem or FileContext instance.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	StorageStatistics.CommonStatisticNames	These are common statistic names.
static class	StorageStatistics.LongStatistic	A 64-bit storage statistic.

Constructor Summary

Constructors

Constructor	Description
StorageStatistics(String name)

Method Summary

Modifier and Type	Method	Description
abstract Long	getLong(String key)	Get the value of a statistic.
abstract Iterator<StorageStatistics.LongStatistic>	getLongStatistics()	Get an iterator over all the currently tracked long statistics.
String	getName()	Get the name of this StorageStatistics object.
String	getScheme()
abstract boolean	isTracked(String key)	Return true if a statistic is being tracked.
abstract void	reset()	Reset all the statistic data.

Methods inherited from class java.lang.Object

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

Constructor Details

StorageStatistics

public StorageStatistics(String name)

Method Details

getName

public String getName()

Get the name of this StorageStatistics object.

Returns:

name of this StorageStatistics object

getScheme

public String getScheme()

Returns:

the associated file system scheme if this is scheme specific, else return null.

getLongStatistics

public abstract Iterator<StorageStatistics.LongStatistic> getLongStatistics()

Get an iterator over all the currently tracked long statistics. The values returned will depend on the type of FileSystem or FileContext object. The values do not necessarily reflect a snapshot in time.

Returns:

LongStatistic Iterator.

getLong

public abstract Long getLong(String key)

Get the value of a statistic.

Parameters:

key - key.

Returns:

null if the statistic is not being tracked or is not a long statistic. The value of the statistic, otherwise.

isTracked

public abstract boolean isTracked(String key)

Return true if a statistic is being tracked.

Parameters:

key - key.

Returns:

True only if the statistic is being tracked.

reset

public abstract void reset()

Reset all the statistic data.