de.unkrig.commons.util.concurrent

Class ConcurrentUtil

java.lang.Object

de.unkrig.commons.util.concurrent.ConcurrentUtil

public final class ConcurrentUtil
extends Object

Utility methods related to "java.util.concurrent".

Field Summary

Fields

Modifier and Type	Field and Description
static ExecutorService	SEQUENTIAL_EXECUTOR_SERVICE An ExecutorService which executes callables in the same thread immediately.

Method Summary

Modifier and Type	Method and Description
static <T> Consumer<T>	aggregate(int n, Consumer<? super List<T>> delegate) Creates and returns a Consumer which, when invoked, acts as follows: First ...
static <T> List<Consumer<T>>	collect(int n, Consumer<? super List<T>> delegate) Creates and returns a list of n consumers; when each of these has been invoked exactly once, then the delegate is invoked with a list of the consumed subjects, in the same order as the consumers.
static Runnable	count(int n, Runnable delegate) Creates and returns a Runnable which, when run, acts as follows: First ...

Methods inherited from class java.lang.Object

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

Field Detail

SEQUENTIAL_EXECUTOR_SERVICE

public static final ExecutorService SEQUENTIAL_EXECUTOR_SERVICE

An ExecutorService which executes callables in the same thread immediately.

Method Detail

count

public static Runnable count(int n,
                             Runnable delegate)

Creates and returns a Runnable which, when run, acts as follows:

First ... (n - 1)th run:

Does nothing

nth run:

Runs the delegate

(n + 1)th and all following runs:

Throws an IllegalStateException

The returned Runnable can be run from any thread.

aggregate

public static <T> Consumer<T> aggregate(int n,
                                        Consumer<? super List<T>> delegate)

Creates and returns a Consumer which, when invoked, acts as follows:

First ... (n - 1)th invocation:

The subject is collected (internally)

nth invocation:

Invokes the delegate with the previously collected subjects, in the same order as the n invocations.

(n + 1)th and all following invocations:

Throws an IllegalStateException

The returned Consumer can be invoked from any thread.

collect

public static <T> List<Consumer<T>> collect(int n,
                                            Consumer<? super List<T>> delegate)

Creates and returns a list of n consumers; when each of these has been invoked exactly once, then the delegate is invoked with a list of the consumed subjects, in the same order as the consumers.

When one of the returned consumers is invoked more than once, then it throws an IllegalStateException.