com.bigdata.util.concurrent

Class MappedTaskExecutor

java.lang.Object

com.bigdata.util.concurrent.MappedTaskExecutor

Deprecated.

by LatchedExecutorService which has higher throughput and plays more nicely with the Executor paradigm.

public class MappedTaskExecutor
extends Object

A fly weight helper class that runs tasks either sequentially or with limited parallelism against some thread pool. Deadlock can arise when limited parallelism is applied if there are dependencies among the tasks. Limited parallelism is enforced by running chunks of tasks in sequence. Higher concurrency is possible when using a dedicated thread pool having the desired number of worker threads.

Version:

$Id$

Author:

Bryan Thompson

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor and Description
MappedTaskExecutor(ExecutorService service) Deprecated.

Method Summary

Methods

Modifier and Type	Method and Description
protected ExecutorService	getThreadPool() Deprecated.
<T> List<T>	runTasks(List<Callable<T>> tasks, long timeout, TimeUnit unit, int maxParallel) Deprecated. Runs a set of tasks, checking their futures.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final transient org.apache.log4j.Logger log

Deprecated.

Constructor Detail

MappedTaskExecutor

public MappedTaskExecutor(ExecutorService service)

Deprecated.

Method Detail

getThreadPool

protected ExecutorService getThreadPool()

Deprecated.

runTasks

public <T> List<T> runTasks(List<Callable<T>> tasks,
                   long timeout,
                   TimeUnit unit,
                   int maxParallel)
                 throws InterruptedException,
                        ExecutionException,
                        TimeoutException

Deprecated.

Runs a set of tasks, checking their futures. When maxParallel is GT ONE (1), tasks are run in chunks of up to maxParallel tasks at once. New chunks are not submitted until all tasks in the existing chunk are complete. Higher concurrency limited parallelism may be obtained with a purpose specific thread pool of a given worker thread capacity, but there is overhead associated with creating the thread pool and its worker threads.

Parameters:

maxParallel - The maximum parallelism. This is ONE (1) to run the tasks sequentially. If the value is 2 or greater, then the tasks will be executed with limited parallelism. You may specify Integer.MAX_VALUE to indicate that this class should not impose any constraint on their parallel execution.

tasks - The tasks to be executed.

Returns:

The list of value returned by the Future(s) of the tasks IFF all tasks were executed successfully.

Throws:

TimeoutException

ExecutionException

InterruptedException