| 12 |
|
import java.util.Collection; |
| 13 |
|
import java.util.Collections; |
| 14 |
|
import java.util.List; |
| 15 |
+ |
import java.util.RandomAccess; |
| 16 |
|
import java.util.Map; |
| 17 |
|
import java.util.WeakHashMap; |
| 18 |
|
|
| 55 |
|
* restriction is in part enforced by not permitting checked |
| 56 |
|
* exceptions such as {@code IOExceptions} to be thrown. However, |
| 57 |
|
* computations may still encounter unchecked exceptions, that are |
| 58 |
< |
* rethrown to callers attempting join them. These exceptions may |
| 58 |
> |
* rethrown to callers attempting to join them. These exceptions may |
| 59 |
|
* additionally include RejectedExecutionExceptions stemming from |
| 60 |
|
* internal resource exhaustion such as failure to allocate internal |
| 61 |
|
* task queues. |
| 86 |
|
* established in a constructor, and then defines a {@code compute} |
| 87 |
|
* method that somehow uses the control methods supplied by this base |
| 88 |
|
* class. While these methods have {@code public} access (to allow |
| 89 |
< |
* instances of different task subclasses to call each others |
| 89 |
> |
* instances of different task subclasses to call each other's |
| 90 |
|
* methods), some of them may only be called from within other |
| 91 |
|
* ForkJoinTasks (as may be determined using method {@link |
| 92 |
|
* #inForkJoinPool}). Attempts to invoke them in other contexts |
| 93 |
|
* result in exceptions or errors, possibly including |
| 94 |
|
* ClassCastException. |
| 95 |
|
* |
| 96 |
< |
* <p>Most base support methods are {@code final} because their |
| 97 |
< |
* implementations are intrinsically tied to the underlying |
| 98 |
< |
* lightweight task scheduling framework, and so cannot be overridden. |
| 99 |
< |
* Developers creating new basic styles of fork/join processing should |
| 100 |
< |
* minimally implement {@code protected} methods |
| 101 |
< |
* {@link #exec}, {@link #setRawResult}, and |
| 102 |
< |
* {@link #getRawResult}, while also introducing an abstract |
| 103 |
< |
* computational method that can be implemented in its subclasses, |
| 104 |
< |
* possibly relying on other {@code protected} methods provided |
| 104 |
< |
* by this class. |
| 96 |
> |
* <p>Most base support methods are {@code final}, to prevent |
| 97 |
> |
* overriding of implementations that are intrinsically tied to the |
| 98 |
> |
* underlying lightweight task scheduling framework. Developers |
| 99 |
> |
* creating new basic styles of fork/join processing should minimally |
| 100 |
> |
* implement {@code protected} methods {@link #exec}, {@link |
| 101 |
> |
* #setRawResult}, and {@link #getRawResult}, while also introducing |
| 102 |
> |
* an abstract computational method that can be implemented in its |
| 103 |
> |
* subclasses, possibly relying on other {@code protected} methods |
| 104 |
> |
* provided by this class. |
| 105 |
|
* |
| 106 |
|
* <p>ForkJoinTasks should perform relatively small amounts of |
| 107 |
< |
* computations, otherwise splitting into smaller tasks. As a very |
| 108 |
< |
* rough rule of thumb, a task should perform more than 100 and less |
| 109 |
< |
* than 10000 basic computational steps. If tasks are too big, then |
| 110 |
< |
* parallelism cannot improve throughput. If too small, then memory |
| 111 |
< |
* and internal task maintenance overhead may overwhelm processing. |
| 107 |
> |
* computation. Large tasks should be split into smaller subtasks, |
| 108 |
> |
* usually via recursive decomposition. As a very rough rule of thumb, |
| 109 |
> |
* a task should perform more than 100 and less than 10000 basic |
| 110 |
> |
* computational steps. If tasks are too big, then parallelism cannot |
| 111 |
> |
* improve throughput. If too small, then memory and internal task |
| 112 |
> |
* maintenance overhead may overwhelm processing. |
| 113 |
|
* |
| 114 |
|
* <p>This class provides {@code adapt} methods for {@link |
| 115 |
|
* java.lang.Runnable} and {@link java.util.concurrent.Callable}, that |
| 117 |
|
* kinds of tasks. When all tasks are of this form, consider using a |
| 118 |
|
* pool in {@link ForkJoinPool#setAsyncMode}. |
| 119 |
|
* |
| 120 |
< |
* <p>ForkJoinTasks are {@code Serializable}, which enables them |
| 121 |
< |
* to be used in extensions such as remote execution frameworks. It is |
| 122 |
< |
* in general sensible to serialize tasks only before or after, but |
| 123 |
< |
* not during execution. Serialization is not relied on during |
| 123 |
< |
* execution itself. |
| 120 |
> |
* <p>ForkJoinTasks are {@code Serializable}, which enables them to be |
| 121 |
> |
* used in extensions such as remote execution frameworks. It is |
| 122 |
> |
* sensible to serialize tasks only before or after, but not during, |
| 123 |
> |
* execution. Serialization is not relied on during execution itself. |
| 124 |
|
* |
| 125 |
|
* @since 1.7 |
| 126 |
|
* @author Doug Lea |
| 496 |
|
/** |
| 497 |
|
* Arranges to asynchronously execute this task. While it is not |
| 498 |
|
* necessarily enforced, it is a usage error to fork a task more |
| 499 |
< |
* than once unless it has completed and been reinitialized. This |
| 500 |
< |
* method may be invoked only from within ForkJoinTask |
| 501 |
< |
* computations (as may be determined using method {@link |
| 502 |
< |
* #inForkJoinPool}). Attempts to invoke in other contexts result |
| 503 |
< |
* in exceptions or errors, possibly including ClassCastException. |
| 499 |
> |
* than once unless it has completed and been reinitialized. |
| 500 |
|
* |
| 501 |
< |
* @return {@code this}, to simplify usage. |
| 501 |
> |
* <p>This method may be invoked only from within {@code |
| 502 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 503 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 504 |
> |
* result in exceptions or errors, possibly including {@code |
| 505 |
> |
* ClassCastException}. |
| 506 |
> |
* |
| 507 |
> |
* @return {@code this}, to simplify usage |
| 508 |
|
*/ |
| 509 |
|
public final ForkJoinTask<V> fork() { |
| 510 |
|
((ForkJoinWorkerThread) Thread.currentThread()) |
| 514 |
|
|
| 515 |
|
/** |
| 516 |
|
* Returns the result of the computation when it is ready. |
| 517 |
< |
* This method differs from {@code get} in that abnormal |
| 518 |
< |
* completion results in RuntimeExceptions or Errors, not |
| 519 |
< |
* ExecutionExceptions. |
| 517 |
> |
* This method differs from {@link #get()} in that |
| 518 |
> |
* abnormal completion results in {@code RuntimeException} or |
| 519 |
> |
* {@code Error}, not {@code ExecutionException}. |
| 520 |
|
* |
| 521 |
|
* @return the computed result |
| 522 |
|
*/ |
| 543 |
|
} |
| 544 |
|
|
| 545 |
|
/** |
| 546 |
< |
* Forks the given tasks, returning when {@code isDone} holds for |
| 547 |
< |
* each task or an exception is encountered. This method may be |
| 548 |
< |
* invoked only from within ForkJoinTask computations (as may be |
| 549 |
< |
* determined using method {@link #inForkJoinPool}). Attempts to |
| 550 |
< |
* invoke in other contexts result in exceptions or errors, |
| 551 |
< |
* possibly including ClassCastException. |
| 546 |
> |
* Forks the given tasks, returning when {@code isDone} holds |
| 547 |
> |
* for each task or an exception is encountered. |
| 548 |
> |
* |
| 549 |
> |
* <p>This method may be invoked only from within {@code |
| 550 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 551 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 552 |
> |
* result in exceptions or errors, possibly including {@code |
| 553 |
> |
* ClassCastException}. |
| 554 |
|
* |
| 555 |
|
* @param t1 the first task |
| 556 |
|
* @param t2 the second task |
| 557 |
|
* @throws NullPointerException if any task is null |
| 558 |
|
* @throws RuntimeException or Error if a task did so |
| 559 |
|
*/ |
| 560 |
< |
public static void invokeAll(ForkJoinTask<?>t1, ForkJoinTask<?> t2) { |
| 560 |
> |
public static void invokeAll(ForkJoinTask<?> t1, ForkJoinTask<?> t2) { |
| 561 |
|
t2.fork(); |
| 562 |
|
t1.invoke(); |
| 563 |
|
t2.join(); |
| 567 |
|
* Forks the given tasks, returning when {@code isDone} holds for |
| 568 |
|
* each task or an exception is encountered. If any task |
| 569 |
|
* encounters an exception, others may be, but are not guaranteed |
| 570 |
< |
* to be, cancelled. This method may be invoked only from within |
| 567 |
< |
* ForkJoinTask computations (as may be determined using method |
| 568 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 569 |
< |
* result in exceptions or errors, possibly including |
| 570 |
< |
* ClassCastException. |
| 570 |
> |
* to be, cancelled. |
| 571 |
|
* |
| 572 |
< |
* Overloadings of this method exist for the special cases |
| 573 |
< |
* of one to four arguments. |
| 572 |
> |
* <p>This method may be invoked only from within {@code |
| 573 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 574 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 575 |
> |
* result in exceptions or errors, possibly including {@code |
| 576 |
> |
* ClassCastException}. |
| 577 |
|
* |
| 578 |
|
* @param tasks the tasks |
| 579 |
|
* @throws NullPointerException if tasks or any element are null |
| 613 |
|
} |
| 614 |
|
|
| 615 |
|
/** |
| 616 |
< |
* Forks all tasks in the collection, returning when {@code |
| 617 |
< |
* isDone} holds for each task or an exception is encountered. If |
| 618 |
< |
* any task encounters an exception, others may be, but are not |
| 619 |
< |
* guaranteed to be, cancelled. This method may be invoked only |
| 620 |
< |
* from within ForkJoinTask computations (as may be determined |
| 621 |
< |
* using method {@link #inForkJoinPool}). Attempts to invoke in |
| 622 |
< |
* other contexts result in exceptions or errors, possibly |
| 623 |
< |
* including ClassCastException. |
| 616 |
> |
* Forks all tasks in the specified collection, returning when |
| 617 |
> |
* {@code isDone} holds for each task or an exception is |
| 618 |
> |
* encountered. If any task encounters an exception, others may |
| 619 |
> |
* be, but are not guaranteed to be, cancelled. The behavior of |
| 620 |
> |
* this operation is undefined if the specified collection is |
| 621 |
> |
* modified while the operation is in progress. |
| 622 |
> |
* |
| 623 |
> |
* <p>This method may be invoked only from within {@code |
| 624 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 625 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 626 |
> |
* result in exceptions or errors, possibly including {@code |
| 627 |
> |
* ClassCastException}. |
| 628 |
|
* |
| 629 |
|
* @param tasks the collection of tasks |
| 630 |
|
* @return the tasks argument, to simplify usage |
| 632 |
|
* @throws RuntimeException or Error if any task did so |
| 633 |
|
*/ |
| 634 |
|
public static <T extends ForkJoinTask<?>> Collection<T> invokeAll(Collection<T> tasks) { |
| 635 |
< |
if (!(tasks instanceof List<?>)) { |
| 635 |
> |
if (!(tasks instanceof RandomAccess) || !(tasks instanceof List<?>)) { |
| 636 |
|
invokeAll(tasks.toArray(new ForkJoinTask<?>[tasks.size()])); |
| 637 |
|
return tasks; |
| 638 |
|
} |
| 692 |
|
} |
| 693 |
|
|
| 694 |
|
/** |
| 695 |
< |
* Asserts that the results of this task's computation will not be |
| 696 |
< |
* used. If a cancellation occurs before attempting to execute this |
| 697 |
< |
* task, execution will be suppressed, {@link #isCancelled} |
| 698 |
< |
* will report true, and {@link #join} will result in a |
| 699 |
< |
* {@code CancellationException} being thrown. Otherwise, when |
| 700 |
< |
* cancellation races with completion, there are no guarantees |
| 701 |
< |
* about whether {@code isCancelled} will report {@code true}, |
| 695 |
< |
* whether {@code join} will return normally or via an exception, |
| 696 |
< |
* or whether these behaviors will remain consistent upon repeated |
| 697 |
< |
* invocation. |
| 695 |
> |
* Attempts to cancel execution of this task. This attempt will |
| 696 |
> |
* fail if the task has already completed, has already been |
| 697 |
> |
* cancelled, or could not be cancelled for some other reason. If |
| 698 |
> |
* successful, and this task has not started when cancel is |
| 699 |
> |
* called, execution of this task is suppressed, {@link |
| 700 |
> |
* #isCancelled} will report true, and {@link #join} will result |
| 701 |
> |
* in a {@code CancellationException} being thrown. |
| 702 |
|
* |
| 703 |
|
* <p>This method may be overridden in subclasses, but if so, must |
| 704 |
|
* still ensure that these minimal properties hold. In particular, |
| 705 |
< |
* the cancel method itself must not throw exceptions. |
| 705 |
> |
* the {@code cancel} method itself must not throw exceptions. |
| 706 |
|
* |
| 707 |
|
* <p>This method is designed to be invoked by <em>other</em> |
| 708 |
|
* tasks. To terminate the current task, you can just return or |
| 710 |
|
* invoke {@link #completeExceptionally}. |
| 711 |
|
* |
| 712 |
|
* @param mayInterruptIfRunning this value is ignored in the |
| 713 |
< |
* default implementation because tasks are not in general |
| 713 |
> |
* default implementation because tasks are not |
| 714 |
|
* cancelled via interruption |
| 715 |
|
* |
| 716 |
|
* @return {@code true} if this task is now cancelled |
| 731 |
|
|
| 732 |
|
/** |
| 733 |
|
* Returns the exception thrown by the base computation, or a |
| 734 |
< |
* CancellationException if cancelled, or null if none or if the |
| 735 |
< |
* method has not yet completed. |
| 734 |
> |
* {@code CancellationException} if cancelled, or {@code null} if |
| 735 |
> |
* none or if the method has not yet completed. |
| 736 |
|
* |
| 737 |
|
* @return the exception, or {@code null} if none |
| 738 |
|
*/ |
| 810 |
|
* there are no potential dependencies between continuation of the |
| 811 |
|
* current task and that of any other task that might be executed |
| 812 |
|
* while helping. (This usually holds for pure divide-and-conquer |
| 813 |
< |
* tasks). This method may be invoked only from within |
| 814 |
< |
* ForkJoinTask computations (as may be determined using method |
| 815 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 816 |
< |
* result in exceptions or errors, possibly including |
| 817 |
< |
* ClassCastException. |
| 813 |
> |
* tasks). |
| 814 |
> |
* |
| 815 |
> |
* <p>This method may be invoked only from within {@code |
| 816 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 817 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 818 |
> |
* result in exceptions or errors, possibly including {@code |
| 819 |
> |
* ClassCastException}. |
| 820 |
|
* |
| 821 |
|
* @return the computed result |
| 822 |
|
*/ |
| 829 |
|
|
| 830 |
|
/** |
| 831 |
|
* Possibly executes other tasks until this task is ready. This |
| 832 |
< |
* method may be invoked only from within ForkJoinTask |
| 833 |
< |
* computations (as may be determined using method {@link |
| 834 |
< |
* #inForkJoinPool}). Attempts to invoke in other contexts result |
| 835 |
< |
* in exceptions or errors, possibly including ClassCastException. |
| 832 |
> |
* method may be useful when processing collections of tasks when |
| 833 |
> |
* some have been cancelled or otherwise known to have aborted. |
| 834 |
> |
* |
| 835 |
> |
* <p>This method may be invoked only from within {@code |
| 836 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 837 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 838 |
> |
* result in exceptions or errors, possibly including {@code |
| 839 |
> |
* ClassCastException}. |
| 840 |
|
*/ |
| 841 |
|
public final void quietlyHelpJoin() { |
| 842 |
|
if (status >= 0) { |
| 875 |
|
|
| 876 |
|
/** |
| 877 |
|
* Possibly executes tasks until the pool hosting the current task |
| 878 |
< |
* {@link ForkJoinPool#isQuiescent}. This method may be of use in |
| 879 |
< |
* designs in which many tasks are forked, but none are explicitly |
| 880 |
< |
* joined, instead executing them until all are processed. This |
| 881 |
< |
* method may be invoked only from within ForkJoinTask |
| 882 |
< |
* computations (as may be determined using method {@link |
| 883 |
< |
* #inForkJoinPool}). Attempts to invoke in other contexts result |
| 884 |
< |
* in exceptions or errors, possibly including ClassCastException. |
| 878 |
> |
* {@link ForkJoinPool#isQuiescent is quiescent}. This method may |
| 879 |
> |
* be of use in designs in which many tasks are forked, but none |
| 880 |
> |
* are explicitly joined, instead executing them until all are |
| 881 |
> |
* processed. |
| 882 |
> |
* |
| 883 |
> |
* <p>This method may be invoked only from within {@code |
| 884 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 885 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 886 |
> |
* result in exceptions or errors, possibly including {@code |
| 887 |
> |
* ClassCastException}. |
| 888 |
|
*/ |
| 889 |
|
public static void helpQuiesce() { |
| 890 |
|
((ForkJoinWorkerThread) Thread.currentThread()) |
| 897 |
|
* this task, but only if reuse occurs when this task has either |
| 898 |
|
* never been forked, or has been forked, then completed and all |
| 899 |
|
* outstanding joins of this task have also completed. Effects |
| 900 |
< |
* under any other usage conditions are not guaranteed, and are |
| 901 |
< |
* discouraged. This method may be useful when executing |
| 900 |
> |
* under any other usage conditions are not guaranteed. |
| 901 |
> |
* This method may be useful when executing |
| 902 |
|
* pre-constructed trees of subtasks in loops. |
| 903 |
|
*/ |
| 904 |
|
public void reinitialize() { |
| 937 |
|
* by the current thread, and has not commenced executing in |
| 938 |
|
* another thread. This method may be useful when arranging |
| 939 |
|
* alternative local processing of tasks that could have been, but |
| 940 |
< |
* were not, stolen. This method may be invoked only from within |
| 941 |
< |
* ForkJoinTask computations (as may be determined using method |
| 942 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 943 |
< |
* result in exceptions or errors, possibly including |
| 944 |
< |
* ClassCastException. |
| 940 |
> |
* were not, stolen. |
| 941 |
> |
* |
| 942 |
> |
* <p>This method may be invoked only from within {@code |
| 943 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 944 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 945 |
> |
* result in exceptions or errors, possibly including {@code |
| 946 |
> |
* ClassCastException}. |
| 947 |
|
* |
| 948 |
|
* @return {@code true} if unforked |
| 949 |
|
*/ |
| 956 |
|
* Returns an estimate of the number of tasks that have been |
| 957 |
|
* forked by the current worker thread but not yet executed. This |
| 958 |
|
* value may be useful for heuristic decisions about whether to |
| 959 |
< |
* fork other tasks. This method may be invoked only from within |
| 960 |
< |
* ForkJoinTask computations (as may be determined using method |
| 961 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 962 |
< |
* result in exceptions or errors, possibly including |
| 963 |
< |
* ClassCastException. |
| 959 |
> |
* fork other tasks. |
| 960 |
> |
* |
| 961 |
> |
* <p>This method may be invoked only from within {@code |
| 962 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 963 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 964 |
> |
* result in exceptions or errors, possibly including {@code |
| 965 |
> |
* ClassCastException}. |
| 966 |
> |
* |
| 967 |
|
* @return the number of tasks |
| 968 |
|
*/ |
| 969 |
|
public static int getQueuedTaskCount() { |
| 979 |
|
* usages of ForkJoinTasks, at steady state, each worker should |
| 980 |
|
* aim to maintain a small constant surplus (for example, 3) of |
| 981 |
|
* tasks, and to process computations locally if this threshold is |
| 982 |
< |
* exceeded. This method may be invoked only from within |
| 983 |
< |
* ForkJoinTask computations (as may be determined using method |
| 984 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 985 |
< |
* result in exceptions or errors, possibly including |
| 986 |
< |
* ClassCastException. * |
| 982 |
> |
* exceeded. |
| 983 |
> |
* |
| 984 |
> |
* <p>This method may be invoked only from within {@code |
| 985 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 986 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 987 |
> |
* result in exceptions or errors, possibly including {@code |
| 988 |
> |
* ClassCastException}. |
| 989 |
> |
* |
| 990 |
|
* @return the surplus number of tasks, which may be negative |
| 991 |
|
*/ |
| 992 |
|
public static int getSurplusQueuedTaskCount() { |
| 1038 |
|
* null even if a task exists but cannot be accessed without |
| 1039 |
|
* contention with other threads. This method is designed |
| 1040 |
|
* primarily to support extensions, and is unlikely to be useful |
| 1041 |
< |
* otherwise. This method may be invoked only from within |
| 1042 |
< |
* ForkJoinTask computations (as may be determined using method |
| 1043 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 1044 |
< |
* result in exceptions or errors, possibly including |
| 1045 |
< |
* ClassCastException. |
| 1041 |
> |
* otherwise. |
| 1042 |
> |
* |
| 1043 |
> |
* <p>This method may be invoked only from within {@code |
| 1044 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 1045 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 1046 |
> |
* result in exceptions or errors, possibly including {@code |
| 1047 |
> |
* ClassCastException}. |
| 1048 |
|
* |
| 1049 |
|
* @return the next task, or {@code null} if none are available |
| 1050 |
|
*/ |
| 1057 |
|
* Unschedules and returns, without executing, the next task |
| 1058 |
|
* queued by the current thread but not yet executed. This method |
| 1059 |
|
* is designed primarily to support extensions, and is unlikely to |
| 1060 |
< |
* be useful otherwise. This method may be invoked only from |
| 1061 |
< |
* within ForkJoinTask computations (as may be determined using |
| 1062 |
< |
* method {@link #inForkJoinPool}). Attempts to invoke in other |
| 1063 |
< |
* contexts result in exceptions or errors, possibly including |
| 1064 |
< |
* ClassCastException. |
| 1060 |
> |
* be useful otherwise. |
| 1061 |
> |
* |
| 1062 |
> |
* <p>This method may be invoked only from within {@code |
| 1063 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 1064 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 1065 |
> |
* result in exceptions or errors, possibly including {@code |
| 1066 |
> |
* ClassCastException}. |
| 1067 |
|
* |
| 1068 |
|
* @return the next task, or {@code null} if none are available |
| 1069 |
|
*/ |
| 1080 |
|
* {@code null} result does not necessarily imply quiescence |
| 1081 |
|
* of the pool this task is operating in. This method is designed |
| 1082 |
|
* primarily to support extensions, and is unlikely to be useful |
| 1083 |
< |
* otherwise. This method may be invoked only from within |
| 1084 |
< |
* ForkJoinTask computations (as may be determined using method |
| 1085 |
< |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 1086 |
< |
* result in exceptions or errors, possibly including |
| 1087 |
< |
* ClassCastException. |
| 1083 |
> |
* otherwise. |
| 1084 |
> |
* |
| 1085 |
> |
* <p>This method may be invoked only from within {@code |
| 1086 |
> |
* ForkJoinTask} computations (as may be determined using method |
| 1087 |
> |
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
| 1088 |
> |
* result in exceptions or errors, possibly including {@code |
| 1089 |
> |
* ClassCastException}. |
| 1090 |
|
* |
| 1091 |
|
* @return a task, or {@code null} if none are available |
| 1092 |
|
*/ |
| 1151 |
|
} |
| 1152 |
|
|
| 1153 |
|
/** |
| 1154 |
< |
* Returns a new ForkJoinTask that performs the {@code run} |
| 1155 |
< |
* method of the given Runnable as its action, and returns a null |
| 1156 |
< |
* result upon {@code join}. |
| 1154 |
> |
* Returns a new {@code ForkJoinTask} that performs the {@code run} |
| 1155 |
> |
* method of the given {@code Runnable} as its action, and returns |
| 1156 |
> |
* a null result upon {@link #join}. |
| 1157 |
|
* |
| 1158 |
|
* @param runnable the runnable action |
| 1159 |
|
* @return the task |
| 1163 |
|
} |
| 1164 |
|
|
| 1165 |
|
/** |
| 1166 |
< |
* Returns a new ForkJoinTask that performs the {@code run} |
| 1167 |
< |
* method of the given Runnable as its action, and returns the |
| 1168 |
< |
* given result upon {@code join}. |
| 1166 |
> |
* Returns a new {@code ForkJoinTask} that performs the {@code run} |
| 1167 |
> |
* method of the given {@code Runnable} as its action, and returns |
| 1168 |
> |
* the given result upon {@link #join}. |
| 1169 |
|
* |
| 1170 |
|
* @param runnable the runnable action |
| 1171 |
|
* @param result the result upon completion |
| 1176 |
|
} |
| 1177 |
|
|
| 1178 |
|
/** |
| 1179 |
< |
* Returns a new ForkJoinTask that performs the {@code call} |
| 1180 |
< |
* method of the given Callable as its action, and returns its |
| 1181 |
< |
* result upon {@code join}, translating any checked |
| 1182 |
< |
* exceptions encountered into {@code RuntimeException}. |
| 1179 |
> |
* Returns a new {@code ForkJoinTask} that performs the {@code call} |
| 1180 |
> |
* method of the given {@code Callable} as its action, and returns |
| 1181 |
> |
* its result upon {@link #join}, translating any checked exceptions |
| 1182 |
> |
* encountered into {@code RuntimeException}. |
| 1183 |
|
* |
| 1184 |
|
* @param callable the callable action |
| 1185 |
|
* @return the task |
