org.apache.oozie.util

Class ChildReaper

java.lang.Object

org.apache.oozie.util.ChildReaper

All Implemented Interfaces:

Closeable, AutoCloseable

public class ChildReaper
extends Object
implements Closeable

Utility to reap empty child nodes of a parent node. Periodically calls getChildren on the node and adds empty nodes to an internally managed Reaper

Constructor Summary

Constructors

Constructor and Description
ChildReaper(org.apache.curator.framework.CuratorFramework client, String path, org.apache.curator.framework.recipes.locks.Reaper.Mode mode)
ChildReaper(org.apache.curator.framework.CuratorFramework client, String path, org.apache.curator.framework.recipes.locks.Reaper.Mode mode, int reapingThresholdMs)
ChildReaper(org.apache.curator.framework.CuratorFramework client, String path, org.apache.curator.framework.recipes.locks.Reaper.Mode mode, ScheduledExecutorService executor, int reapingThresholdMs)
ChildReaper(org.apache.curator.framework.CuratorFramework client, String path, org.apache.curator.framework.recipes.locks.Reaper.Mode mode, ScheduledExecutorService executor, int reapingThresholdMs, String leaderPath)

Method Summary

Methods

Modifier and Type	Method and Description
ChildReaper	addPath(String path) Add a path to reap children from
void	close()
static <E> Set<E>	newConcurrentHashSet() Creates a thread-safe set backed by a hash map.
boolean	removePath(String path) Remove a path from reaping
void	start() The reaper must be started

Methods inherited from class java.lang.Object

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

Constructor Detail

ChildReaper

public ChildReaper(org.apache.curator.framework.CuratorFramework client,
           String path,
           org.apache.curator.framework.recipes.locks.Reaper.Mode mode)

Parameters:

client - the client

path - path to reap children from

mode - reaping mode

ChildReaper

public ChildReaper(org.apache.curator.framework.CuratorFramework client,
           String path,
           org.apache.curator.framework.recipes.locks.Reaper.Mode mode,
           int reapingThresholdMs)

Parameters:

client - the client

path - path to reap children from

reapingThresholdMs - threshold in milliseconds that determines that a path can be deleted

mode - reaping mode

ChildReaper

public ChildReaper(org.apache.curator.framework.CuratorFramework client,
           String path,
           org.apache.curator.framework.recipes.locks.Reaper.Mode mode,
           ScheduledExecutorService executor,
           int reapingThresholdMs)

Parameters:

client - the client

path - path to reap children from

executor - executor to use for background tasks

reapingThresholdMs - threshold in milliseconds that determines that a path can be deleted

mode - reaping mode

ChildReaper

public ChildReaper(org.apache.curator.framework.CuratorFramework client,
           String path,
           org.apache.curator.framework.recipes.locks.Reaper.Mode mode,
           ScheduledExecutorService executor,
           int reapingThresholdMs,
           String leaderPath)

Parameters:

client - the client

path - path to reap children from

executor - executor to use for background tasks

reapingThresholdMs - threshold in milliseconds that determines that a path can be deleted

mode - reaping mode

leaderPath - if not null, uses a leader selection so that only 1 reaper is active in the cluster

Method Detail

newConcurrentHashSet

public static <E> Set<E> newConcurrentHashSet()

Creates a thread-safe set backed by a hash map. The set is backed by a ConcurrentHashMap instance, and thus carries the same concurrency guarantees.

Unlike HashSet, this class does NOT allow null to be used as an element. The set is serializable.

Returns:

a new, empty thread-safe Set

Since:

15.0

start

public void start()
           throws Exception

The reaper must be started

Throws:

Exception - errors

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

addPath

public ChildReaper addPath(String path)

Add a path to reap children from

Parameters:

path - the path

Returns:

this for chaining

removePath

public boolean removePath(String path)

Remove a path from reaping

Parameters:

path - the path

Returns:

true if the path existed and was removed