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Diffstat (limited to 'src/actors/scala/actors/threadpool/Future.java')
-rw-r--r-- | src/actors/scala/actors/threadpool/Future.java | 142 |
1 files changed, 0 insertions, 142 deletions
diff --git a/src/actors/scala/actors/threadpool/Future.java b/src/actors/scala/actors/threadpool/Future.java deleted file mode 100644 index 5e1b3d414a..0000000000 --- a/src/actors/scala/actors/threadpool/Future.java +++ /dev/null @@ -1,142 +0,0 @@ -/* - * Written by Doug Lea with assistance from members of JCP JSR-166 - * Expert Group and released to the public domain, as explained at - * http://creativecommons.org/licenses/publicdomain - */ - -package scala.actors.threadpool; -import scala.actors.threadpool.*; // for javadoc (till 6280605 is fixed) - -/** - * A <tt>Future</tt> represents the result of an asynchronous - * computation. Methods are provided to check if the computation is - * complete, to wait for its completion, and to retrieve the result of - * the computation. The result can only be retrieved using method - * <tt>get</tt> when the computation has completed, blocking if - * necessary until it is ready. Cancellation is performed by the - * <tt>cancel</tt> method. Additional methods are provided to - * determine if the task completed normally or was cancelled. Once a - * computation has completed, the computation cannot be cancelled. - * If you would like to use a <tt>Future</tt> for the sake - * of cancellability but not provide a usable result, you can - * declare types of the form <tt>Future<?></tt> and - * return <tt>null</tt> as a result of the underlying task. - * - * <p> - * <b>Sample Usage</b> (Note that the following classes are all - * made-up.) <p> - * <pre> - * interface ArchiveSearcher { String search(String target); } - * class App { - * ExecutorService executor = ... - * ArchiveSearcher searcher = ... - * void showSearch(final String target) - * throws InterruptedException { - * Future<String> future - * = executor.submit(new Callable<String>() { - * public String call() { - * return searcher.search(target); - * }}); - * displayOtherThings(); // do other things while searching - * try { - * displayText(future.get()); // use future - * } catch (ExecutionException ex) { cleanup(); return; } - * } - * } - * </pre> - * - * The {@link FutureTask} class is an implementation of <tt>Future</tt> that - * implements <tt>Runnable</tt>, and so may be executed by an <tt>Executor</tt>. - * For example, the above construction with <tt>submit</tt> could be replaced by: - * <pre> - * FutureTask<String> future = - * new FutureTask<String>(new Callable<String>() { - * public String call() { - * return searcher.search(target); - * }}); - * executor.execute(future); - * </pre> - * - * <p>Memory consistency effects: Actions taken by the asynchronous computation - * <a href="package-summary.html#MemoryVisibility"> <i>happen-before</i></a> - * actions following the corresponding {@code Future.get()} in another thread. - * - * @see FutureTask - * @see Executor - * @since 1.5 - * @author Doug Lea - */ -public interface Future { - - /** - * Attempts to cancel execution of this task. This attempt will - * fail if the task has already completed, has already been cancelled, - * or could not be cancelled for some other reason. If successful, - * and this task has not started when <tt>cancel</tt> is called, - * this task should never run. If the task has already started, - * then the <tt>mayInterruptIfRunning</tt> parameter determines - * whether the thread executing this task should be interrupted in - * an attempt to stop the task. - * - * <p>After this method returns, subsequent calls to {@link #isDone} will - * always return <tt>true</tt>. Subsequent calls to {@link #isCancelled} - * will always return <tt>true</tt> if this method returned <tt>true</tt>. - * - * @param mayInterruptIfRunning <tt>true</tt> if the thread executing this - * task should be interrupted; otherwise, in-progress tasks are allowed - * to complete - * @return <tt>false</tt> if the task could not be cancelled, - * typically because it has already completed normally; - * <tt>true</tt> otherwise - */ - boolean cancel(boolean mayInterruptIfRunning); - - /** - * Returns <tt>true</tt> if this task was cancelled before it completed - * normally. - * - * @return <tt>true</tt> if this task was cancelled before it completed - */ - boolean isCancelled(); - - /** - * Returns <tt>true</tt> if this task completed. - * - * Completion may be due to normal termination, an exception, or - * cancellation -- in all of these cases, this method will return - * <tt>true</tt>. - * - * @return <tt>true</tt> if this task completed - */ - boolean isDone(); - - /** - * Waits if necessary for the computation to complete, and then - * retrieves its result. - * - * @return the computed result - * @throws CancellationException if the computation was cancelled - * @throws ExecutionException if the computation threw an - * exception - * @throws InterruptedException if the current thread was interrupted - * while waiting - */ - Object get() throws InterruptedException, ExecutionException; - - /** - * Waits if necessary for at most the given time for the computation - * to complete, and then retrieves its result, if available. - * - * @param timeout the maximum time to wait - * @param unit the time unit of the timeout argument - * @return the computed result - * @throws CancellationException if the computation was cancelled - * @throws ExecutionException if the computation threw an - * exception - * @throws InterruptedException if the current thread was interrupted - * while waiting - * @throws TimeoutException if the wait timed out - */ - Object get(long timeout, TimeUnit unit) - throws InterruptedException, ExecutionException, TimeoutException; -} |