Package org.forgerock.openig.thread

Class ScheduledExecutorServiceHeaplet

java.lang.Object

org.forgerock.openig.heap.GenericHeaplet

org.forgerock.openig.thread.ScheduledExecutorServiceHeaplet

All Implemented Interfaces:

Heaplet

public class ScheduledExecutorServiceHeaplet
extends GenericHeaplet

Heaplet for building ScheduledExecutorService instances.

Creates a thread pool that can schedule commands to run after a given delay, or to execute periodically.

Reference:

     
     {
         "type": "ScheduledExecutorService",
         "config": {
             "corePoolSize":  integer > 0 [ OPTIONAL - default to 1 (will grow as needed)]
             "gracefulStop":  boolean     [ OPTIONAL - default to true (all running jobs will complete)]
             "gracePeriod" :  duration    [ OPTIONAL - default to '10 second']
         }
     }
     
 

Usage:

     
     {
         "type": "ScheduledExecutorService",
         "config": {
             "corePoolSize": 42 // defaults to 1 (will grow as needed), only positive and non-zero
         }
     }
     
 

This class supports graceful stop. gracefulStop is a setting that allows a thread pool to wind down nicely before killing aggressively running (and submitted) jobs.

     
     {
         "gracefulStop": false // defaults to true
     }
     
 

gracefulPeriod attribute defines how long the heaplet should wait for jobs to actually terminate properly.

Note that this setting is only considered when gracefulStop is set to true.

     
     {
         "gracePeriod": "20 seconds" // defaults to 10 seconds
     }
     
 

When the period is over, if the executor service is not properly terminated, the heaplet prints a message and drains the queued tasks and notify the running tasks for interruption.

Note that all configuration attributes can be defined using static expressions (they can't be resolved against context or request objects that are not available at init time).

See Also:

• ExecutorService.shutdown()
• ExecutorService.shutdownNow()
• ExecutorService.awaitTermination(long, java.util.concurrent.TimeUnit)
• ExecutorService.isTerminated()

Field Summary

Fields inherited from class org.forgerock.openig.heap.GenericHeaplet

config, heap, name, object, qualified

Constructor Summary

Constructors

Constructor	Description
ScheduledExecutorServiceHeaplet()

Method Summary

Modifier and Type	Method	Description
ExecutorService	create()	Called to request the heaplet create an object.
void	destroy()	Called to indicate that the object created by the heaplet is going to be dereferenced.

Methods inherited from class org.forgerock.openig.heap.GenericHeaplet

create, endpointRegistry, evaluatedWithHeapProperties, expression, getConfig, getHeap, getType, initialBindings, meterRegistryHolder, start

Methods inherited from class java.lang.Object

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

Constructor Details

ScheduledExecutorServiceHeaplet

public ScheduledExecutorServiceHeaplet()

Method Details

create

public ExecutorService create()
                       throws HeapException

Description copied from class: GenericHeaplet

Called to request the heaplet create an object. Called by Heaplet.create(Name, JsonValue, Heap) after initializing the protected field members. Implementations should parse configuration but not acquire resources, start threads, or log any initialization messages. These tasks should be performed by the GenericHeaplet.start() method.

Specified by:

create in class GenericHeaplet

Returns:

The created object.

Throws:

HeapException - if an exception occurred during creation of the heap object or any of its dependencies.

destroy

public void destroy()

Description copied from interface: Heaplet

Called to indicate that the object created by the heaplet is going to be dereferenced. This gives the heaplet an opportunity to free any resources that are being held prior to its dereference.

Specified by:

destroy in interface Heaplet

Overrides:

destroy in class GenericHeaplet