com.ajjpj.afoundation.concurrent.ATaskScheduler Maven / Gradle / Ivy
package com.ajjpj.afoundation.concurrent;
import com.ajjpj.afoundation.function.AFunction1;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
/**
* A TaskScheduler can schedule tasks to threads, i.e. it represents a thread pool. While similar to an ExecutorService, it however requires an explicit timeout
* to be specified for every task. The timeout is measured from the moment the task is submitted. If the timeout is reached before the task is completed,
* the task fails at that moment, triggering failure callbacks on the returned {@link AFuture AFuture}.
*
* The result of submitting a task is an {@link AFuture AFuture} instance. While similar in principle to {@link java.util.concurrent.Future java.util.concurrent.Future}, it supports functional
* and non-blocking programming.
*
* @author arno
*/
public interface ATaskScheduler {
/**
* Submits a task with a given timeout.
*/
AFuture submit (Callable task, long timeout, TimeUnit timeoutUnit);
/**
* Submits a task without a result, and a separate result value. If the task finishes without an exception and before the timeout occurs, the explicit result value is
* bound to the resulting future.
*/
AFuture submit (Runnable task, T result, long timeout, TimeUnit timeoutUnit);
/**
* This is a convenience method for submitting a list of task based on a list of input values. Each task consists of applying the taskFunction parameter
* to one of the input values.
*
* Put differently, this method loops over the param values. For each of them, it submits a Callable that applies the taskFunction to that
* value.
*
* The timeout applies to every submitted task separately.
*/
List> submitAll (List params, AFunction1 taskFunction, long timeout, TimeUnit timeoutUnit);
/**
* This is a convenience method that is simular to submitAll. The only difference is that this method provides every returned future with a default value as
* if calling {@link AFuture#withDefaultValue future.withDefaultValue(defaultValue)} on each of the returned futures.
*
* Put differently, the returned futures will never fail but return the default value whenever they would otherwise have failed.
*/
List> submitAllWithDefaultValue (List params, AFunction1 taskFunction, long timeout, TimeUnit timeoutUnit, R defaultValue);
}