Uses of Class java.util.concurrent.CountedCompleter (Java Platform SE 8 )
Date: 2026-04-17

## Uses of Class
java.util.concurrent.CountedCompleter

- Packages that use CountedCompleter
  Package | Description
  --- | ---
  java.util.concurrent | Utility classes commonly useful in concurrent programming.

- - ### Uses of CountedCompleter in java.util.concurrent

    Methods in java.util.concurrent that return CountedCompleter
    Modifier and Type | Method and Description
    --- | ---
    `CountedCompleter<?>` | CountedCompleter.`firstComplete()` If this task's pending count is zero, returns this task; otherwise decrements its pending count and returns `null`.
    `CountedCompleter<?>` | CountedCompleter.`getCompleter()` Returns the completer established in this task's constructor, or `null` if none.
    `CountedCompleter<?>` | CountedCompleter.`getRoot()` Returns the root of the current computation; i.e., this task if it has no completer, else its completer's root.
    `CountedCompleter<?>` | CountedCompleter.`nextComplete()` If this task does not have a completer, invokes `ForkJoinTask.quietlyComplete()` and returns `null`.

    Methods in java.util.concurrent with parameters of type CountedCompleter
    Modifier and Type | Method and Description
    --- | ---
    `void` | CountedCompleter.`onCompletion(CountedCompleter<?> caller)` Performs an action when method `tryComplete()` is invoked and the pending count is zero, or when the unconditional method `complete(T)` is invoked.
    `boolean` | CountedCompleter.`onExceptionalCompletion(Throwable ex, CountedCompleter<?> caller)` Performs an action when method `ForkJoinTask.completeExceptionally(Throwable)` is invoked or method `compute()` throws an exception, and this task has not already otherwise completed normally.

    Constructors in java.util.concurrent with parameters of type CountedCompleter
    Constructor and Description
    `CountedCompleter(CountedCompleter<?> completer)` Creates a new CountedCompleter with the given completer and an initial pending count of zero.
    `CountedCompleter(CountedCompleter<?> completer, int initialPendingCount)` Creates a new CountedCompleter with the given completer and initial pending count.

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