Package org.apache.accumulo.core.spi.fs

Class DelegatingChooser

java.lang.Object

org.apache.accumulo.core.spi.fs.DelegatingChooser

All Implemented Interfaces:

VolumeChooser

public class DelegatingChooser
extends Object
implements VolumeChooser

A VolumeChooser that delegates to another volume chooser based on other properties: table.custom.volume.chooser for tables, and general.custom.volume.chooser.scoped for scopes. general.custom.volume.chooser.{scope} can override the system-wide setting for general.custom.volume.chooser.scoped. At the time this was written, the only known scope was "logger".

Since:

2.1.0

Constructor Summary

Constructors

Constructor	Description
DelegatingChooser()

Method Summary

Modifier and Type	Method	Description
Set<String>	choosable(VolumeChooserEnvironment env, Set<String> options)	Return the subset of all possible volumes that could be chosen across all invocations of VolumeChooser.choose(VolumeChooserEnvironment, Set). This is currently used to determine if the chosen volumes can support the required filesystem operations for write ahead logs. There may be other use cases in the future.
String	choose(VolumeChooserEnvironment env, Set<String> options)	Choose a volume from the provided options.

Methods inherited from class java.lang.Object

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

Constructor Details

DelegatingChooser

public DelegatingChooser()

Method Details

choose

public String choose(VolumeChooserEnvironment env,
 Set<String> options)

Description copied from interface: VolumeChooser

Choose a volume from the provided options.

Specified by:

choose in interface VolumeChooser

Parameters:

env - the server environment provided by the calling framework

options - the list of volumes to choose from

Returns:

a volume from the list of volume options

choosable

public Set<String> choosable(VolumeChooserEnvironment env,
 Set<String> options)

Description copied from interface: VolumeChooser

Return the subset of all possible volumes that could be chosen across all invocations of VolumeChooser.choose(VolumeChooserEnvironment, Set).
This is currently used to determine if the chosen volumes can support the required filesystem operations for write ahead logs.
There may be other use cases in the future.

Specified by:

choosable in interface VolumeChooser