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root/jsr166/jsr166/src/jsr166y/ForkJoinTask.java
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Comparing jsr166/src/jsr166y/ForkJoinTask.java (file contents):
Revision 1.38 by dl, Tue Aug 4 22:47:08 2009 UTC vs.
Revision 1.45 by jsr166, Thu Oct 22 08:19:44 2009 UTC

# Line 56 | Line 56 | import java.util.WeakHashMap;
56   * exceptions such as {@code IOExceptions} to be thrown. However,
57   * computations may still encounter unchecked exceptions, that are
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.
59 > * additionally include {@link RejectedExecutionException} stemming
60 > * from internal resource exhaustion, such as failure to allocate
61 > * internal task queues.
62   *
63   * <p>The primary method for awaiting completion and extracting
64   * results of a task is {@link #join}, but there are several variants:
# Line 80 | Line 80 | import java.util.WeakHashMap;
80   * <p>The execution status of tasks may be queried at several levels
81   * of detail: {@link #isDone} is true if a task completed in any way
82   * (including the case where a task was cancelled without executing);
83 * {@link #isCancelled} is true if completion was due to cancellation;
83   * {@link #isCompletedNormally} is true if a task completed without
84 < * cancellation or encountering an exception; {@link
85 < * #isCompletedExceptionally} is true if if the task encountered an
86 < * exception (in which case {@link #getException} returns the
87 < * exception); {@link #isCancelled} is true if the task was cancelled
88 < * (in which case {@link #getException} returns a {@link
89 < * java.util.concurrent.CancellationException}); and {@link
90 < * #isCompletedAbnormally} is true if a task was either cancelled or
92 < * encountered an exception.
84 > * cancellation or encountering an exception; {@link #isCancelled} is
85 > * true if the task was cancelled (in which case {@link #getException}
86 > * returns a {@link java.util.concurrent.CancellationException}); and
87 > * {@link #isCompletedAbnormally} is true if a task was either
88 > * cancelled or encountered an exception, in which case {@link
89 > * #getException} will return either the encountered exception or
90 > * {@link java.util.concurrent.CancellationException}.
91   *
92   * <p>The ForkJoinTask class is not usually directly subclassed.
93   * Instead, you subclass one of the abstract classes that support a
# Line 513 | Line 511 | public abstract class ForkJoinTask<V> im
511       * Arranges to asynchronously execute this task.  While it is not
512       * necessarily enforced, it is a usage error to fork a task more
513       * than once unless it has completed and been reinitialized.
514 +     * Subsequent modifications to the state of this task or any data
515 +     * it operates on are not necessarily consistently observable by
516 +     * any thread other than the one executing it unless preceded by a
517 +     * call to {@link #join} or related methods, or a call to {@link
518 +     * #isDone} returning {@code true}.
519       *
520       * <p>This method may be invoked only from within {@code
521       * ForkJoinTask} computations (as may be determined using method
# Line 529 | Line 532 | public abstract class ForkJoinTask<V> im
532      }
533  
534      /**
535 <     * Returns the result of the computation when it is ready.
535 >     * Returns the result of the computation when it {@link #isDone is done}.
536       * This method differs from {@link #get()} in that
537       * abnormal completion results in {@code RuntimeException} or
538       * {@code Error}, not {@code ExecutionException}.
# Line 560 | Line 563 | public abstract class ForkJoinTask<V> im
563      /**
564       * Forks the given tasks, returning when {@code isDone} holds for
565       * each task or an (unchecked) exception is encountered, in which
566 <     * case the exception is rethrown.  If more than one task
567 <     * encounters an exception, then this method throws any one of
568 <     * these exceptions.  The individual status of each task may be
566 >     * case the exception is rethrown.  If either task encounters an
567 >     * exception, the other one may be, but is not guaranteed to be,
568 >     * cancelled.  If both tasks throw an exception, then this method
569 >     * throws one of them.  The individual status of each task may be
570       * checked using {@link #getException()} and related methods.
571       *
572       * <p>This method may be invoked only from within {@code
# Line 725 | Line 729 | public abstract class ForkJoinTask<V> im
729          return (status & COMPLETION_MASK) == CANCELLED;
730      }
731  
728    /**
729     * Returns {@code true} if the computation performed by this task
730     * has completed (or has been cancelled).
731     *
732     * @return {@code true} if this computation has completed
733     */
732      public final boolean isDone() {
733          return status < 0;
734      }
735  
738    /**
739     * Returns {@code true} if this task was cancelled.
740     *
741     * @return {@code true} if this task was cancelled
742     */
736      public final boolean isCancelled() {
737          return (status & COMPLETION_MASK) == CANCELLED;
738      }
# Line 765 | Line 758 | public abstract class ForkJoinTask<V> im
758      }
759  
760      /**
768     * Returns {@code true} if this task threw an exception.
769     *
770     * @return {@code true} if this task threw an exception
771     */
772    public final boolean isCompletedExceptionally() {
773        return (status & COMPLETION_MASK) == EXCEPTIONAL;
774    }
775
776    /**
761       * Returns the exception thrown by the base computation, or a
762       * {@code CancellationException} if cancelled, or {@code null} if
763       * none or if the method has not yet completed.
# Line 797 | Line 781 | public abstract class ForkJoinTask<V> im
781       * overridable, but overridden versions must invoke {@code super}
782       * implementation to maintain guarantees.
783       *
784 <     * @param ex the exception to throw. If this exception is
785 <     * not a RuntimeException or Error, the actual exception thrown
786 <     * will be a RuntimeException with cause ex.
784 >     * @param ex the exception to throw. If this exception is not a
785 >     * {@code RuntimeException} or {@code Error}, the actual exception
786 >     * thrown will be a {@code RuntimeException} with cause {@code ex}.
787       */
788      public void completeExceptionally(Throwable ex) {
789          setDoneExceptionally((ex instanceof RuntimeException) ||
# Line 846 | Line 830 | public abstract class ForkJoinTask<V> im
830      }
831  
832      /**
833 <     * Possibly executes other tasks until this task is ready, then
834 <     * returns the result of the computation.  This method may be more
835 <     * efficient than {@code join}, but is only applicable when
836 <     * there are no potential dependencies between continuation of the
837 <     * current task and that of any other task that might be executed
838 <     * while helping. (This usually holds for pure divide-and-conquer
839 <     * tasks).
833 >     * Possibly executes other tasks until this task {@link #isDone is
834 >     * done}, then returns the result of the computation.  This method
835 >     * may be more efficient than {@code join}, but is only applicable
836 >     * when there are no potential dependencies between continuation
837 >     * of the current task and that of any other task that might be
838 >     * executed while helping. (This usually holds for pure
839 >     * divide-and-conquer tasks).
840       *
841       * <p>This method may be invoked only from within {@code
842       * ForkJoinTask} computations (as may be determined using method
# Line 870 | Line 854 | public abstract class ForkJoinTask<V> im
854      }
855  
856      /**
857 <     * Possibly executes other tasks until this task is ready.  This
858 <     * method may be useful when processing collections of tasks when
859 <     * some have been cancelled or otherwise known to have aborted.
857 >     * Possibly executes other tasks until this task {@link #isDone is
858 >     * done}.  This method may be useful when processing collections
859 >     * of tasks when some have been cancelled or otherwise known to
860 >     * have aborted.
861       *
862       * <p>This method may be invoked only from within {@code
863       * ForkJoinTask} computations (as may be determined using method
# Line 1234 | Line 1219 | public abstract class ForkJoinTask<V> im
1219      private static final long serialVersionUID = -7721805057305804111L;
1220  
1221      /**
1222 <     * Save the state to a stream.
1222 >     * Saves the state to a stream.
1223       *
1224       * @serialData the current run status and the exception thrown
1225       * during execution, or {@code null} if none
# Line 1247 | Line 1232 | public abstract class ForkJoinTask<V> im
1232      }
1233  
1234      /**
1235 <     * Reconstitute the instance from a stream.
1235 >     * Reconstitutes the instance from a stream.
1236       *
1237       * @param s the stream
1238       */

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