Package org.hortonmachine.gears.libs.modules.multiprocessing

Class ExecutionPlanner

java.lang.Object

org.hortonmachine.gears.libs.modules.multiprocessing.ExecutionPlanner

Direct Known Subclasses:

FixedChunkSizePlanner, InThreadExecutionPlanner

public abstract class ExecutionPlanner
extends Object

An ExecutionPlanner provides the logic to distribute the processing of many small MultiProcessingTasks over a limited number of execution threads. This is crucial for efficient parallel execution.

Author:

Falko Bräutigam

Field Summary

Fields

Modifier and Type	Field	Description
static BlockingExecutorService	defaultExecutor	The default ExecutorService to be used by all planners.
static Supplier<ExecutionPlanner>	defaultPlannerFactory	Set this to change the default planner for all modules.
protected int	numberOfTasks

Constructor Summary

Constructors

Constructor	Description
ExecutionPlanner()

Method Summary

Modifier and Type	Method	Description
static ExecutionPlanner	createDefaultPlanner()	Creates a new general purpose, default ExecutionPlanner.
abstract void	join()	Blocks the calling thread until all sumitted task have completed execution.
ExecutionPlanner	setNumberOfTasks(int num)	Hints this planner about the total number of task until next join().
abstract void	submit(MultiProcessingTask task)	Submits the given task for execution.

Methods inherited from class java.lang.Object

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

Field Detail

defaultExecutor

public static final BlockingExecutorService defaultExecutor

The default ExecutorService to be used by all planners.

Set this to change the default. The ExecutorService must not have an unbound queue or an unlimited number of threads. In other words, the executor has to refuse submits when system resources are running out.

defaultPlannerFactory

public static Supplier<ExecutionPlanner> defaultPlannerFactory

Set this to change the default planner for all modules.

numberOfTasks

protected int numberOfTasks

Constructor Detail

ExecutionPlanner

public ExecutionPlanner()

Method Detail

createDefaultPlanner

public static ExecutionPlanner createDefaultPlanner()

Creates a new general purpose, default ExecutionPlanner. This is returned by MultiProcessing.createDefaultPlanner() by default.

setNumberOfTasks

public ExecutionPlanner setNumberOfTasks(int num)

Hints this planner about the total number of task until next join().

submit

public abstract void submit(MultiProcessingTask task)

Submits the given task for execution.

Parameters:

task -

join

public abstract void join()
                   throws Exception

Blocks the calling thread until all sumitted task have completed execution.

Throws:

Exception - If a previously submitted task has thrown an exception then it is re-thrown by the join() method.