com.bigdata.util.concurrent

Class ShutdownHelper

java.lang.Object

com.bigdata.util.concurrent.ShutdownHelper

public class ShutdownHelper
extends Object

Helper class for normal shutdown of an ExecutorService.

Version:

$Id$

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.apache.log4j.Logger	log

Constructor Summary

Constructors

Constructor and Description
ShutdownHelper(ExecutorService executorService) Issues the ExecutorService.shutdown() request and then waits until all tasks running on that service have terminated.
ShutdownHelper(ExecutorService executorService, long logTimeout, TimeUnit unit) Issues the ExecutorService.shutdown() request and then waits until all tasks running on that service have terminated.

Method Summary

Methods

Modifier and Type	Method and Description
long	elapsed() The elapsed nanoseconds since the ExecutorService.shutdown() was initiated.
protected void	logTimeout() Invoked each time the logTimeout expires awaiting the service termination.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.log4j.Logger log

Constructor Detail

ShutdownHelper

public ShutdownHelper(ExecutorService executorService)
               throws InterruptedException

Issues the ExecutorService.shutdown() request and then waits until all tasks running on that service have terminated.

If the caller's Thread is interrupted while awaiting service termination, then the caller is responsible for the subsequent behavior. Common actions include continuing to await shutdown of the service, e.g., by invoking this method again, immediately terminating the service, etc.

Parameters:

executorService - The service to be shutdown.

Throws:

InterruptedException - If interrupted while awaiting termination of the service.

ShutdownHelper

public ShutdownHelper(ExecutorService executorService,
              long logTimeout,
              TimeUnit unit)
               throws InterruptedException

Issues the ExecutorService.shutdown() request and then waits until all tasks running on that service have terminated.

If the caller's Thread is interrupted while awaiting service termination, then the caller is responsible for the subsequent behavior. Common actions include continuing to await shutdown of the service, e.g., by invoking this method again, immediately terminating the service, etc.

Parameters:

executorService - The service to be shutdown.

logTimeout - The timeout between #logTimeout(ExecutorService, long, Logger) notifications.

unit - The unit in which that timeout is expressed.

Throws:

IllegalArgumentException - if executorService is null.

IllegalArgumentException - if logTimeout is non-positive.

IllegalArgumentException - if unit is null.

InterruptedException - If interrupted while awaiting termination of the service.

Method Detail

elapsed

public long elapsed()

The elapsed nanoseconds since the ExecutorService.shutdown() was initiated. This value is updated every 100ms until the service is terminated.

logTimeout

protected void logTimeout()

Invoked each time the logTimeout expires awaiting the service termination. The default implementation is a NOP, but it may be overriden in order to log a message, etc.