Package org.rrd4j.core

Class RrdSyncThreadPool

java.lang.Object

org.rrd4j.core.RrdSyncThreadPool

public class RrdSyncThreadPool
extends Object

Thread pool used by RrdNioBackend instances to periodically sync the mapped file to disk. Note that instances of RrdSyncThreadPool must be disposed of by calling shutdown().

For ease of use in standalone applications, clients may choose to register a shutdown hook by calling registerShutdownHook(). However, in web applications it is best to explicitly shutdown() the pool when the application is un-deployed, usually within a javax.servlet.ServletContextListener.

Since:

2.2

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	RrdSyncThreadPool.DaemonThreadFactory	Daemon thread factory used by the monitor executors.

Constructor Summary

Constructors

Constructor	Description
RrdSyncThreadPool()	Creates a new RrdSyncThreadPool with a default pool size of 6.
RrdSyncThreadPool(int syncPoolSize)	Creates a new RrdSyncThreadPool with the given pool size.
RrdSyncThreadPool(int syncPoolSize, ThreadFactory threadFactory)	Creates a new RrdSyncThreadPool with the given pool size.
RrdSyncThreadPool(ScheduledExecutorService syncExecutor)	Creates a new RrdSyncThreadPool with a user-provided ScheduledExecutorService.

Method Summary

Modifier and Type	Method	Description
RrdSyncThreadPool	registerShutdownHook()	Registers a shutdown hook that destroys the underlying thread pool when when the JVM is about to quit.
(package private) ScheduledFuture<?>	scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit)
void	shutdown()	Shuts down this thread pool in an orderly manner.
void	unregisterShutdownHook()	Unregisters the shutdown hook installed by registerShutdownHook().

Methods inherited from class java.lang.Object

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

Constructor Details

RrdSyncThreadPool

public RrdSyncThreadPool()

Creates a new RrdSyncThreadPool with a default pool size of 6.

RrdSyncThreadPool

public RrdSyncThreadPool(ScheduledExecutorService syncExecutor)

Creates a new RrdSyncThreadPool with a user-provided ScheduledExecutorService.

Parameters:

syncExecutor - the ScheduledExecutorService to use for sync'ing mapped files to disk

RrdSyncThreadPool

public RrdSyncThreadPool(int syncPoolSize)

Creates a new RrdSyncThreadPool with the given pool size.

Parameters:

syncPoolSize - the number of threads to use to sync the mapped file to disk

RrdSyncThreadPool

public RrdSyncThreadPool(int syncPoolSize,
 ThreadFactory threadFactory)

Creates a new RrdSyncThreadPool with the given pool size. Threads will be created by threadFactory.

Parameters:

syncPoolSize - the number of threads to use to sync the mapped file to disk

threadFactory - the ThreadFactory to use for creating threads

Method Details

registerShutdownHook

public RrdSyncThreadPool registerShutdownHook()

Registers a shutdown hook that destroys the underlying thread pool when when the JVM is about to quit.

Returns:

this

See Also:

• unregisterShutdownHook()

unregisterShutdownHook

public void unregisterShutdownHook()

Unregisters the shutdown hook installed by registerShutdownHook(). Has no effect if the hook is not currently installed.

See Also:

• unregisterShutdownHook()

shutdown

public void shutdown()

Shuts down this thread pool in an orderly manner. Has no effect if it has already been called previously.

scheduleWithFixedDelay

ScheduledFuture<?> scheduleWithFixedDelay(Runnable command,
 long initialDelay,
 long delay,
 TimeUnit unit)