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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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package java.util.concurrent; |
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import java.util.function.Supplier; |
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import java.util.function.Consumer; |
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import java.util.function.BiConsumer; |
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import java.util.function.Function; |
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import java.util.function.BiFunction; |
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import java.util.concurrent.Future; |
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import java.util.concurrent.TimeUnit; |
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import java.util.concurrent.ForkJoinPool; |
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import java.util.concurrent.ForkJoinTask; |
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import java.util.concurrent.Executor; |
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import java.util.concurrent.ThreadLocalRandom; |
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import java.util.concurrent.ExecutionException; |
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import java.util.concurrent.TimeoutException; |
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import java.util.concurrent.CancellationException; |
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import java.util.concurrent.atomic.AtomicInteger; |
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import java.util.concurrent.locks.LockSupport; |
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|
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/** |
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* A {@link Future} that may be explicitly completed (setting its |
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* value and status), and may include dependent functions and actions |
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* that trigger upon its completion. |
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* |
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* <p>When two or more threads attempt to |
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* {@link #complete complete}, |
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* {@link #completeExceptionally completeExceptionally}, or |
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* {@link #cancel cancel} |
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* a CompletableFuture, only one of them succeeds. |
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* |
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* <p>Methods are available for adding dependents based on Functions, |
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* Consumers, and Runnables. The appropriate form to use depends on |
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* whether actions require arguments and/or produce results. Actions |
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* may also be triggered after either or both the current and another |
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* CompletableFuture complete. Multiple CompletableFutures may also |
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* be grouped as one using {@link #anyOf(CompletableFuture...)} and |
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* {@link #allOf(CompletableFuture...)}. |
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* |
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* <p>Actions supplied for dependent completions (mainly using methods |
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* with prefix {@code then}) may be performed by the thread that |
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* completes the current CompletableFuture, or by any other caller of |
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* these methods. There are no guarantees about the order of |
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* processing completions unless constrained by these methods. |
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* |
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* <p>Since (unlike {@link FutureTask}) this class has no direct |
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* control over the computation that causes it to be completed, |
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* cancellation is treated as just another form of exceptional completion. |
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* Method {@link #cancel cancel} has the same effect as |
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* {@code completeExceptionally(new CancellationException())}. |
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* |
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* <p>Upon exceptional completion (including cancellation), or when a |
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* completion entails an additional computation which terminates |
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* abruptly with an (unchecked) exception or error, then all of their |
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* dependent completions (and their dependents in turn) generally act |
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* as {@code completeExceptionally} with a {@link CompletionException} |
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* holding that exception as its cause. However, the {@link |
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* #exceptionally exceptionally} and {@link #handle handle} |
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* completions <em>are</em> able to handle exceptional completions of |
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* the CompletableFutures they depend on. |
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* |
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* <p>In case of exceptional completion with a CompletionException, |
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* methods {@link #get()} and {@link #get(long, TimeUnit)} throw an |
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* {@link ExecutionException} with the same cause as held in the |
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* corresponding CompletionException. However, in these cases, |
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* methods {@link #join()} and {@link #getNow} throw the |
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* CompletionException, which simplifies usage. |
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* |
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* <p>CompletableFutures themselves do not execute asynchronously. |
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* However, the {@code async} methods provide commonly useful ways to |
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* commence asynchronous processing, using either a given {@link |
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* Executor} or by default the {@link ForkJoinPool#commonPool()}, of a |
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* function or action that will result in the completion of a new |
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* CompletableFuture. To simplify monitoring, debugging, and tracking, |
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* all generated asynchronous tasks are instances of the tagging |
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* interface {@link AsynchronousCompletionTask}. |
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* |
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* @author Doug Lea |
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* @since 1.8 |
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*/ |
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public class CompletableFuture<T> implements Future<T> { |
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|
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/* |
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* Overview: |
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* |
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* 1. Non-nullness of field result (set via CAS) indicates done. |
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* An AltResult is used to box null as a result, as well as to |
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* hold exceptions. Using a single field makes completion fast |
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* and simple to detect and trigger, at the expense of a lot of |
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* encoding and decoding that infiltrates many methods. One minor |
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* simplification relies on the (static) NIL (to box null results) |
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* being the only AltResult with a null exception field, so we |
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* don't usually need explicit comparisons with NIL. The CF |
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* exception propagation mechanics surrounding decoding rely on |
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* unchecked casts of decoded results really being unchecked, |
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* where user type errors are caught at point of use, as is |
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* currently the case in Java. These are highlighted by using |
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* SuppressWarnings-annotated temporaries. |
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* |
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* 2. Waiters are held in a Treiber stack similar to the one used |
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* in FutureTask, Phaser, and SynchronousQueue. See their |
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* internal documentation for algorithmic details. |
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* |
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* 3. Completions are also kept in a list/stack, and pulled off |
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* and run when completion is triggered. (We could even use the |
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* same stack as for waiters, but would give up the potential |
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* parallelism obtained because woken waiters help release/run |
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* others -- see method postComplete). Because post-processing |
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* may race with direct calls, class Completion opportunistically |
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* extends AtomicInteger so callers can claim the action via |
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* compareAndSet(0, 1). The Completion.run methods are all |
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* written a boringly similar uniform way (that sometimes includes |
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* unnecessary-looking checks, kept to maintain uniformity). |
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* There are enough dimensions upon which they differ that |
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* attempts to factor commonalities while maintaining efficiency |
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* require more lines of code than they would save. |
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* |
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* 4. The exported then/and/or methods do support a bit of |
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* factoring (see doThenApply etc). They must cope with the |
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* intrinsic races surrounding addition of a dependent action |
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* versus performing the action directly because the task is |
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* already complete. For example, a CF may not be complete upon |
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* entry, so a dependent completion is added, but by the time it |
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* is added, the target CF is complete, so must be directly |
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* executed. This is all done while avoiding unnecessary object |
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* construction in safe-bypass cases. |
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*/ |
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|
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// preliminaries |
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|
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static final class AltResult { |
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final Throwable ex; // null only for NIL |
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AltResult(Throwable ex) { this.ex = ex; } |
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} |
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|
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static final AltResult NIL = new AltResult(null); |
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|
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// Fields |
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|
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volatile Object result; // Either the result or boxed AltResult |
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volatile WaitNode waiters; // Treiber stack of threads blocked on get() |
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volatile CompletionNode completions; // list (Treiber stack) of completions |
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|
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// Basic utilities for triggering and processing completions |
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|
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/** |
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* Removes and signals all waiting threads and runs all completions. |
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*/ |
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final void postComplete() { |
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WaitNode q; Thread t; |
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while ((q = waiters) != null) { |
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if (UNSAFE.compareAndSwapObject(this, WAITERS, q, q.next) && |
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(t = q.thread) != null) { |
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q.thread = null; |
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LockSupport.unpark(t); |
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} |
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} |
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|
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CompletionNode h; Completion c; |
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while ((h = completions) != null) { |
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if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, h, h.next) && |
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(c = h.completion) != null) |
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c.run(); |
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} |
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} |
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|
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/** |
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* Triggers completion with the encoding of the given arguments: |
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* if the exception is non-null, encodes it as a wrapped |
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* CompletionException unless it is one already. Otherwise uses |
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* the given result, boxed as NIL if null. |
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*/ |
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final void internalComplete(Object v, Throwable ex) { |
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if (result == null) |
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UNSAFE.compareAndSwapObject |
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(this, RESULT, null, |
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(ex == null) ? (v == null) ? NIL : v : |
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new AltResult((ex instanceof CompletionException) ? ex : |
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new CompletionException(ex))); |
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postComplete(); // help out even if not triggered |
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} |
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|
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/** |
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* If triggered, helps release and/or process completions. |
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*/ |
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final void helpPostComplete() { |
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if (result != null) |
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postComplete(); |
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} |
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|
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/* ------------- waiting for completions -------------- */ |
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|
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/** Number of processors, for spin control */ |
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static final int NCPU = Runtime.getRuntime().availableProcessors(); |
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|
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/** |
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* Heuristic spin value for waitingGet() before blocking on |
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* multiprocessors |
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*/ |
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static final int SPINS = (NCPU > 1) ? 1 << 8 : 0; |
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|
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/** |
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* Linked nodes to record waiting threads in a Treiber stack. See |
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* other classes such as Phaser and SynchronousQueue for more |
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* detailed explanation. This class implements ManagedBlocker to |
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* avoid starvation when blocking actions pile up in |
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* ForkJoinPools. |
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*/ |
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static final class WaitNode implements ForkJoinPool.ManagedBlocker { |
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long nanos; // wait time if timed |
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final long deadline; // non-zero if timed |
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volatile int interruptControl; // > 0: interruptible, < 0: interrupted |
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volatile Thread thread; |
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volatile WaitNode next; |
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WaitNode(boolean interruptible, long nanos, long deadline) { |
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this.thread = Thread.currentThread(); |
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this.interruptControl = interruptible ? 1 : 0; |
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this.nanos = nanos; |
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this.deadline = deadline; |
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} |
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public boolean isReleasable() { |
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if (thread == null) |
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return true; |
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if (Thread.interrupted()) { |
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int i = interruptControl; |
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interruptControl = -1; |
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if (i > 0) |
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return true; |
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} |
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if (deadline != 0L && |
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(nanos <= 0L || (nanos = deadline - System.nanoTime()) <= 0L)) { |
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thread = null; |
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return true; |
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} |
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return false; |
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} |
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public boolean block() { |
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if (isReleasable()) |
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return true; |
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else if (deadline == 0L) |
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LockSupport.park(this); |
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else if (nanos > 0L) |
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LockSupport.parkNanos(this, nanos); |
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return isReleasable(); |
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} |
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} |
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|
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/** |
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* Returns raw result after waiting, or null if interruptible and |
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* interrupted. |
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*/ |
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private Object waitingGet(boolean interruptible) { |
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WaitNode q = null; |
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boolean queued = false; |
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int spins = SPINS; |
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for (Object r;;) { |
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if ((r = result) != null) { |
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if (q != null) { // suppress unpark |
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q.thread = null; |
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if (q.interruptControl < 0) { |
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if (interruptible) { |
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removeWaiter(q); |
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return null; |
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} |
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Thread.currentThread().interrupt(); |
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} |
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} |
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postComplete(); // help release others |
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return r; |
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} |
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else if (spins > 0) { |
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int rnd = ThreadLocalRandom.nextSecondarySeed(); |
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if (rnd == 0) |
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rnd = ThreadLocalRandom.current().nextInt(); |
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if (rnd >= 0) |
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--spins; |
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} |
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else if (q == null) |
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q = new WaitNode(interruptible, 0L, 0L); |
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else if (!queued) |
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queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
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q.next = waiters, q); |
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else if (interruptible && q.interruptControl < 0) { |
288 |
removeWaiter(q); |
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return null; |
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} |
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else if (q.thread != null && result == null) { |
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try { |
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ForkJoinPool.managedBlock(q); |
294 |
} catch (InterruptedException ex) { |
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q.interruptControl = -1; |
296 |
} |
297 |
} |
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} |
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} |
300 |
|
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/** |
302 |
* Awaits completion or aborts on interrupt or timeout. |
303 |
* |
304 |
* @param nanos time to wait |
305 |
* @return raw result |
306 |
*/ |
307 |
private Object timedAwaitDone(long nanos) |
308 |
throws InterruptedException, TimeoutException { |
309 |
WaitNode q = null; |
310 |
boolean queued = false; |
311 |
for (Object r;;) { |
312 |
if ((r = result) != null) { |
313 |
if (q != null) { |
314 |
q.thread = null; |
315 |
if (q.interruptControl < 0) { |
316 |
removeWaiter(q); |
317 |
throw new InterruptedException(); |
318 |
} |
319 |
} |
320 |
postComplete(); |
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return r; |
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} |
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else if (q == null) { |
324 |
if (nanos <= 0L) |
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throw new TimeoutException(); |
326 |
long d = System.nanoTime() + nanos; |
327 |
q = new WaitNode(true, nanos, d == 0L ? 1L : d); // avoid 0 |
328 |
} |
329 |
else if (!queued) |
330 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
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q.next = waiters, q); |
332 |
else if (q.interruptControl < 0) { |
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removeWaiter(q); |
334 |
throw new InterruptedException(); |
335 |
} |
336 |
else if (q.nanos <= 0L) { |
337 |
if (result == null) { |
338 |
removeWaiter(q); |
339 |
throw new TimeoutException(); |
340 |
} |
341 |
} |
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else if (q.thread != null && result == null) { |
343 |
try { |
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ForkJoinPool.managedBlock(q); |
345 |
} catch (InterruptedException ex) { |
346 |
q.interruptControl = -1; |
347 |
} |
348 |
} |
349 |
} |
350 |
} |
351 |
|
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/** |
353 |
* Tries to unlink a timed-out or interrupted wait node to avoid |
354 |
* accumulating garbage. Internal nodes are simply unspliced |
355 |
* without CAS since it is harmless if they are traversed anyway |
356 |
* by releasers. To avoid effects of unsplicing from already |
357 |
* removed nodes, the list is retraversed in case of an apparent |
358 |
* race. This is slow when there are a lot of nodes, but we don't |
359 |
* expect lists to be long enough to outweigh higher-overhead |
360 |
* schemes. |
361 |
*/ |
362 |
private void removeWaiter(WaitNode node) { |
363 |
if (node != null) { |
364 |
node.thread = null; |
365 |
retry: |
366 |
for (;;) { // restart on removeWaiter race |
367 |
for (WaitNode pred = null, q = waiters, s; q != null; q = s) { |
368 |
s = q.next; |
369 |
if (q.thread != null) |
370 |
pred = q; |
371 |
else if (pred != null) { |
372 |
pred.next = s; |
373 |
if (pred.thread == null) // check for race |
374 |
continue retry; |
375 |
} |
376 |
else if (!UNSAFE.compareAndSwapObject(this, WAITERS, q, s)) |
377 |
continue retry; |
378 |
} |
379 |
break; |
380 |
} |
381 |
} |
382 |
} |
383 |
|
384 |
/* ------------- Async tasks -------------- */ |
385 |
|
386 |
/** |
387 |
* A tagging interface identifying asynchronous tasks produced by |
388 |
* {@code async} methods. This may be useful for monitoring, |
389 |
* debugging, and tracking asynchronous activities. |
390 |
*/ |
391 |
public static interface AsynchronousCompletionTask { |
392 |
} |
393 |
|
394 |
/** Base class can act as either FJ or plain Runnable */ |
395 |
abstract static class Async extends ForkJoinTask<Void> |
396 |
implements Runnable, AsynchronousCompletionTask { |
397 |
public final Void getRawResult() { return null; } |
398 |
public final void setRawResult(Void v) { } |
399 |
public final void run() { exec(); } |
400 |
} |
401 |
|
402 |
static final class AsyncRun extends Async { |
403 |
final Runnable fn; |
404 |
final CompletableFuture<Void> dst; |
405 |
AsyncRun(Runnable fn, CompletableFuture<Void> dst) { |
406 |
this.fn = fn; this.dst = dst; |
407 |
} |
408 |
public final boolean exec() { |
409 |
CompletableFuture<Void> d; Throwable ex; |
410 |
if ((d = this.dst) != null && d.result == null) { |
411 |
try { |
412 |
fn.run(); |
413 |
ex = null; |
414 |
} catch (Throwable rex) { |
415 |
ex = rex; |
416 |
} |
417 |
d.internalComplete(null, ex); |
418 |
} |
419 |
return true; |
420 |
} |
421 |
private static final long serialVersionUID = 5232453952276885070L; |
422 |
} |
423 |
|
424 |
static final class AsyncSupply<U> extends Async { |
425 |
final Supplier<U> fn; |
426 |
final CompletableFuture<U> dst; |
427 |
AsyncSupply(Supplier<U> fn, CompletableFuture<U> dst) { |
428 |
this.fn = fn; this.dst = dst; |
429 |
} |
430 |
public final boolean exec() { |
431 |
CompletableFuture<U> d; U u; Throwable ex; |
432 |
if ((d = this.dst) != null && d.result == null) { |
433 |
try { |
434 |
u = fn.get(); |
435 |
ex = null; |
436 |
} catch (Throwable rex) { |
437 |
ex = rex; |
438 |
u = null; |
439 |
} |
440 |
d.internalComplete(u, ex); |
441 |
} |
442 |
return true; |
443 |
} |
444 |
private static final long serialVersionUID = 5232453952276885070L; |
445 |
} |
446 |
|
447 |
static final class AsyncApply<T,U> extends Async { |
448 |
final Function<? super T,? extends U> fn; |
449 |
final T arg; |
450 |
final CompletableFuture<U> dst; |
451 |
AsyncApply(T arg, Function<? super T,? extends U> fn, |
452 |
CompletableFuture<U> dst) { |
453 |
this.arg = arg; this.fn = fn; this.dst = dst; |
454 |
} |
455 |
public final boolean exec() { |
456 |
CompletableFuture<U> d; U u; Throwable ex; |
457 |
if ((d = this.dst) != null && d.result == null) { |
458 |
try { |
459 |
u = fn.apply(arg); |
460 |
ex = null; |
461 |
} catch (Throwable rex) { |
462 |
ex = rex; |
463 |
u = null; |
464 |
} |
465 |
d.internalComplete(u, ex); |
466 |
} |
467 |
return true; |
468 |
} |
469 |
private static final long serialVersionUID = 5232453952276885070L; |
470 |
} |
471 |
|
472 |
static final class AsyncBiApply<T,U,V> extends Async { |
473 |
final BiFunction<? super T,? super U,? extends V> fn; |
474 |
final T arg1; |
475 |
final U arg2; |
476 |
final CompletableFuture<V> dst; |
477 |
AsyncBiApply(T arg1, U arg2, |
478 |
BiFunction<? super T,? super U,? extends V> fn, |
479 |
CompletableFuture<V> dst) { |
480 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
481 |
} |
482 |
public final boolean exec() { |
483 |
CompletableFuture<V> d; V v; Throwable ex; |
484 |
if ((d = this.dst) != null && d.result == null) { |
485 |
try { |
486 |
v = fn.apply(arg1, arg2); |
487 |
ex = null; |
488 |
} catch (Throwable rex) { |
489 |
ex = rex; |
490 |
v = null; |
491 |
} |
492 |
d.internalComplete(v, ex); |
493 |
} |
494 |
return true; |
495 |
} |
496 |
private static final long serialVersionUID = 5232453952276885070L; |
497 |
} |
498 |
|
499 |
static final class AsyncAccept<T> extends Async { |
500 |
final Consumer<? super T> fn; |
501 |
final T arg; |
502 |
final CompletableFuture<Void> dst; |
503 |
AsyncAccept(T arg, Consumer<? super T> fn, |
504 |
CompletableFuture<Void> dst) { |
505 |
this.arg = arg; this.fn = fn; this.dst = dst; |
506 |
} |
507 |
public final boolean exec() { |
508 |
CompletableFuture<Void> d; Throwable ex; |
509 |
if ((d = this.dst) != null && d.result == null) { |
510 |
try { |
511 |
fn.accept(arg); |
512 |
ex = null; |
513 |
} catch (Throwable rex) { |
514 |
ex = rex; |
515 |
} |
516 |
d.internalComplete(null, ex); |
517 |
} |
518 |
return true; |
519 |
} |
520 |
private static final long serialVersionUID = 5232453952276885070L; |
521 |
} |
522 |
|
523 |
static final class AsyncBiAccept<T,U> extends Async { |
524 |
final BiConsumer<? super T,? super U> fn; |
525 |
final T arg1; |
526 |
final U arg2; |
527 |
final CompletableFuture<Void> dst; |
528 |
AsyncBiAccept(T arg1, U arg2, |
529 |
BiConsumer<? super T,? super U> fn, |
530 |
CompletableFuture<Void> dst) { |
531 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
532 |
} |
533 |
public final boolean exec() { |
534 |
CompletableFuture<Void> d; Throwable ex; |
535 |
if ((d = this.dst) != null && d.result == null) { |
536 |
try { |
537 |
fn.accept(arg1, arg2); |
538 |
ex = null; |
539 |
} catch (Throwable rex) { |
540 |
ex = rex; |
541 |
} |
542 |
d.internalComplete(null, ex); |
543 |
} |
544 |
return true; |
545 |
} |
546 |
private static final long serialVersionUID = 5232453952276885070L; |
547 |
} |
548 |
|
549 |
static final class AsyncCompose<T,U> extends Async { |
550 |
final Function<? super T, CompletableFuture<U>> fn; |
551 |
final T arg; |
552 |
final CompletableFuture<U> dst; |
553 |
AsyncCompose(T arg, |
554 |
Function<? super T, CompletableFuture<U>> fn, |
555 |
CompletableFuture<U> dst) { |
556 |
this.arg = arg; this.fn = fn; this.dst = dst; |
557 |
} |
558 |
public final boolean exec() { |
559 |
CompletableFuture<U> d, fr; U u; Throwable ex; |
560 |
if ((d = this.dst) != null && d.result == null) { |
561 |
try { |
562 |
fr = fn.apply(arg); |
563 |
ex = null; |
564 |
} catch (Throwable rex) { |
565 |
ex = rex; |
566 |
fr = null; |
567 |
} |
568 |
if (ex != null) |
569 |
u = null; |
570 |
else if (fr == null) { |
571 |
ex = new NullPointerException(); |
572 |
u = null; |
573 |
} |
574 |
else { |
575 |
Object r = fr.result; |
576 |
if (r instanceof AltResult) { |
577 |
ex = ((AltResult)r).ex; |
578 |
u = null; |
579 |
} |
580 |
else { |
581 |
@SuppressWarnings("unchecked") U ur = (U) r; |
582 |
u = ur; |
583 |
} |
584 |
} |
585 |
d.internalComplete(u, ex); |
586 |
} |
587 |
return true; |
588 |
} |
589 |
private static final long serialVersionUID = 5232453952276885070L; |
590 |
} |
591 |
|
592 |
/* ------------- Completions -------------- */ |
593 |
|
594 |
/** |
595 |
* Simple linked list nodes to record completions, used in |
596 |
* basically the same way as WaitNodes. (We separate nodes from |
597 |
* the Completions themselves mainly because for the And and Or |
598 |
* methods, the same Completion object resides in two lists.) |
599 |
*/ |
600 |
static final class CompletionNode { |
601 |
final Completion completion; |
602 |
volatile CompletionNode next; |
603 |
CompletionNode(Completion completion) { this.completion = completion; } |
604 |
} |
605 |
|
606 |
// Opportunistically subclass AtomicInteger to use compareAndSet to claim. |
607 |
abstract static class Completion extends AtomicInteger implements Runnable { |
608 |
} |
609 |
|
610 |
static final class ApplyCompletion<T,U> extends Completion { |
611 |
final CompletableFuture<? extends T> src; |
612 |
final Function<? super T,? extends U> fn; |
613 |
final CompletableFuture<U> dst; |
614 |
final Executor executor; |
615 |
ApplyCompletion(CompletableFuture<? extends T> src, |
616 |
Function<? super T,? extends U> fn, |
617 |
CompletableFuture<U> dst, Executor executor) { |
618 |
this.src = src; this.fn = fn; this.dst = dst; |
619 |
this.executor = executor; |
620 |
} |
621 |
public final void run() { |
622 |
final CompletableFuture<? extends T> a; |
623 |
final Function<? super T,? extends U> fn; |
624 |
final CompletableFuture<U> dst; |
625 |
Object r; T t; Throwable ex; |
626 |
if ((dst = this.dst) != null && |
627 |
(fn = this.fn) != null && |
628 |
(a = this.src) != null && |
629 |
(r = a.result) != null && |
630 |
compareAndSet(0, 1)) { |
631 |
if (r instanceof AltResult) { |
632 |
ex = ((AltResult)r).ex; |
633 |
t = null; |
634 |
} |
635 |
else { |
636 |
ex = null; |
637 |
@SuppressWarnings("unchecked") T tr = (T) r; |
638 |
t = tr; |
639 |
} |
640 |
Executor e = executor; |
641 |
U u = null; |
642 |
if (ex == null) { |
643 |
try { |
644 |
if (e != null) |
645 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
646 |
else |
647 |
u = fn.apply(t); |
648 |
} catch (Throwable rex) { |
649 |
ex = rex; |
650 |
} |
651 |
} |
652 |
if (e == null || ex != null) |
653 |
dst.internalComplete(u, ex); |
654 |
} |
655 |
} |
656 |
private static final long serialVersionUID = 5232453952276885070L; |
657 |
} |
658 |
|
659 |
static final class AcceptCompletion<T> extends Completion { |
660 |
final CompletableFuture<? extends T> src; |
661 |
final Consumer<? super T> fn; |
662 |
final CompletableFuture<Void> dst; |
663 |
final Executor executor; |
664 |
AcceptCompletion(CompletableFuture<? extends T> src, |
665 |
Consumer<? super T> fn, |
666 |
CompletableFuture<Void> dst, Executor executor) { |
667 |
this.src = src; this.fn = fn; this.dst = dst; |
668 |
this.executor = executor; |
669 |
} |
670 |
public final void run() { |
671 |
final CompletableFuture<? extends T> a; |
672 |
final Consumer<? super T> fn; |
673 |
final CompletableFuture<Void> dst; |
674 |
Object r; T t; Throwable ex; |
675 |
if ((dst = this.dst) != null && |
676 |
(fn = this.fn) != null && |
677 |
(a = this.src) != null && |
678 |
(r = a.result) != null && |
679 |
compareAndSet(0, 1)) { |
680 |
if (r instanceof AltResult) { |
681 |
ex = ((AltResult)r).ex; |
682 |
t = null; |
683 |
} |
684 |
else { |
685 |
ex = null; |
686 |
@SuppressWarnings("unchecked") T tr = (T) r; |
687 |
t = tr; |
688 |
} |
689 |
Executor e = executor; |
690 |
if (ex == null) { |
691 |
try { |
692 |
if (e != null) |
693 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
694 |
else |
695 |
fn.accept(t); |
696 |
} catch (Throwable rex) { |
697 |
ex = rex; |
698 |
} |
699 |
} |
700 |
if (e == null || ex != null) |
701 |
dst.internalComplete(null, ex); |
702 |
} |
703 |
} |
704 |
private static final long serialVersionUID = 5232453952276885070L; |
705 |
} |
706 |
|
707 |
static final class RunCompletion<T> extends Completion { |
708 |
final CompletableFuture<? extends T> src; |
709 |
final Runnable fn; |
710 |
final CompletableFuture<Void> dst; |
711 |
final Executor executor; |
712 |
RunCompletion(CompletableFuture<? extends T> src, |
713 |
Runnable fn, |
714 |
CompletableFuture<Void> dst, |
715 |
Executor executor) { |
716 |
this.src = src; this.fn = fn; this.dst = dst; |
717 |
this.executor = executor; |
718 |
} |
719 |
public final void run() { |
720 |
final CompletableFuture<? extends T> a; |
721 |
final Runnable fn; |
722 |
final CompletableFuture<Void> dst; |
723 |
Object r; Throwable ex; |
724 |
if ((dst = this.dst) != null && |
725 |
(fn = this.fn) != null && |
726 |
(a = this.src) != null && |
727 |
(r = a.result) != null && |
728 |
compareAndSet(0, 1)) { |
729 |
if (r instanceof AltResult) |
730 |
ex = ((AltResult)r).ex; |
731 |
else |
732 |
ex = null; |
733 |
Executor e = executor; |
734 |
if (ex == null) { |
735 |
try { |
736 |
if (e != null) |
737 |
e.execute(new AsyncRun(fn, dst)); |
738 |
else |
739 |
fn.run(); |
740 |
} catch (Throwable rex) { |
741 |
ex = rex; |
742 |
} |
743 |
} |
744 |
if (e == null || ex != null) |
745 |
dst.internalComplete(null, ex); |
746 |
} |
747 |
} |
748 |
private static final long serialVersionUID = 5232453952276885070L; |
749 |
} |
750 |
|
751 |
static final class BiApplyCompletion<T,U,V> extends Completion { |
752 |
final CompletableFuture<? extends T> src; |
753 |
final CompletableFuture<? extends U> snd; |
754 |
final BiFunction<? super T,? super U,? extends V> fn; |
755 |
final CompletableFuture<V> dst; |
756 |
final Executor executor; |
757 |
BiApplyCompletion(CompletableFuture<? extends T> src, |
758 |
CompletableFuture<? extends U> snd, |
759 |
BiFunction<? super T,? super U,? extends V> fn, |
760 |
CompletableFuture<V> dst, Executor executor) { |
761 |
this.src = src; this.snd = snd; |
762 |
this.fn = fn; this.dst = dst; |
763 |
this.executor = executor; |
764 |
} |
765 |
public final void run() { |
766 |
final CompletableFuture<? extends T> a; |
767 |
final CompletableFuture<? extends U> b; |
768 |
final BiFunction<? super T,? super U,? extends V> fn; |
769 |
final CompletableFuture<V> dst; |
770 |
Object r, s; T t; U u; Throwable ex; |
771 |
if ((dst = this.dst) != null && |
772 |
(fn = this.fn) != null && |
773 |
(a = this.src) != null && |
774 |
(r = a.result) != null && |
775 |
(b = this.snd) != null && |
776 |
(s = b.result) != null && |
777 |
compareAndSet(0, 1)) { |
778 |
if (r instanceof AltResult) { |
779 |
ex = ((AltResult)r).ex; |
780 |
t = null; |
781 |
} |
782 |
else { |
783 |
ex = null; |
784 |
@SuppressWarnings("unchecked") T tr = (T) r; |
785 |
t = tr; |
786 |
} |
787 |
if (ex != null) |
788 |
u = null; |
789 |
else if (s instanceof AltResult) { |
790 |
ex = ((AltResult)s).ex; |
791 |
u = null; |
792 |
} |
793 |
else { |
794 |
@SuppressWarnings("unchecked") U us = (U) s; |
795 |
u = us; |
796 |
} |
797 |
Executor e = executor; |
798 |
V v = null; |
799 |
if (ex == null) { |
800 |
try { |
801 |
if (e != null) |
802 |
e.execute(new AsyncBiApply<T,U,V>(t, u, fn, dst)); |
803 |
else |
804 |
v = fn.apply(t, u); |
805 |
} catch (Throwable rex) { |
806 |
ex = rex; |
807 |
} |
808 |
} |
809 |
if (e == null || ex != null) |
810 |
dst.internalComplete(v, ex); |
811 |
} |
812 |
} |
813 |
private static final long serialVersionUID = 5232453952276885070L; |
814 |
} |
815 |
|
816 |
static final class BiAcceptCompletion<T,U> extends Completion { |
817 |
final CompletableFuture<? extends T> src; |
818 |
final CompletableFuture<? extends U> snd; |
819 |
final BiConsumer<? super T,? super U> fn; |
820 |
final CompletableFuture<Void> dst; |
821 |
final Executor executor; |
822 |
BiAcceptCompletion(CompletableFuture<? extends T> src, |
823 |
CompletableFuture<? extends U> snd, |
824 |
BiConsumer<? super T,? super U> fn, |
825 |
CompletableFuture<Void> dst, Executor executor) { |
826 |
this.src = src; this.snd = snd; |
827 |
this.fn = fn; this.dst = dst; |
828 |
this.executor = executor; |
829 |
} |
830 |
public final void run() { |
831 |
final CompletableFuture<? extends T> a; |
832 |
final CompletableFuture<? extends U> b; |
833 |
final BiConsumer<? super T,? super U> fn; |
834 |
final CompletableFuture<Void> dst; |
835 |
Object r, s; T t; U u; Throwable ex; |
836 |
if ((dst = this.dst) != null && |
837 |
(fn = this.fn) != null && |
838 |
(a = this.src) != null && |
839 |
(r = a.result) != null && |
840 |
(b = this.snd) != null && |
841 |
(s = b.result) != null && |
842 |
compareAndSet(0, 1)) { |
843 |
if (r instanceof AltResult) { |
844 |
ex = ((AltResult)r).ex; |
845 |
t = null; |
846 |
} |
847 |
else { |
848 |
ex = null; |
849 |
@SuppressWarnings("unchecked") T tr = (T) r; |
850 |
t = tr; |
851 |
} |
852 |
if (ex != null) |
853 |
u = null; |
854 |
else if (s instanceof AltResult) { |
855 |
ex = ((AltResult)s).ex; |
856 |
u = null; |
857 |
} |
858 |
else { |
859 |
@SuppressWarnings("unchecked") U us = (U) s; |
860 |
u = us; |
861 |
} |
862 |
Executor e = executor; |
863 |
if (ex == null) { |
864 |
try { |
865 |
if (e != null) |
866 |
e.execute(new AsyncBiAccept<T,U>(t, u, fn, dst)); |
867 |
else |
868 |
fn.accept(t, u); |
869 |
} catch (Throwable rex) { |
870 |
ex = rex; |
871 |
} |
872 |
} |
873 |
if (e == null || ex != null) |
874 |
dst.internalComplete(null, ex); |
875 |
} |
876 |
} |
877 |
private static final long serialVersionUID = 5232453952276885070L; |
878 |
} |
879 |
|
880 |
static final class BiRunCompletion<T> extends Completion { |
881 |
final CompletableFuture<? extends T> src; |
882 |
final CompletableFuture<?> snd; |
883 |
final Runnable fn; |
884 |
final CompletableFuture<Void> dst; |
885 |
final Executor executor; |
886 |
BiRunCompletion(CompletableFuture<? extends T> src, |
887 |
CompletableFuture<?> snd, |
888 |
Runnable fn, |
889 |
CompletableFuture<Void> dst, Executor executor) { |
890 |
this.src = src; this.snd = snd; |
891 |
this.fn = fn; this.dst = dst; |
892 |
this.executor = executor; |
893 |
} |
894 |
public final void run() { |
895 |
final CompletableFuture<? extends T> a; |
896 |
final CompletableFuture<?> b; |
897 |
final Runnable fn; |
898 |
final CompletableFuture<Void> dst; |
899 |
Object r, s; Throwable ex; |
900 |
if ((dst = this.dst) != null && |
901 |
(fn = this.fn) != null && |
902 |
(a = this.src) != null && |
903 |
(r = a.result) != null && |
904 |
(b = this.snd) != null && |
905 |
(s = b.result) != null && |
906 |
compareAndSet(0, 1)) { |
907 |
if (r instanceof AltResult) |
908 |
ex = ((AltResult)r).ex; |
909 |
else |
910 |
ex = null; |
911 |
if (ex == null && (s instanceof AltResult)) |
912 |
ex = ((AltResult)s).ex; |
913 |
Executor e = executor; |
914 |
if (ex == null) { |
915 |
try { |
916 |
if (e != null) |
917 |
e.execute(new AsyncRun(fn, dst)); |
918 |
else |
919 |
fn.run(); |
920 |
} catch (Throwable rex) { |
921 |
ex = rex; |
922 |
} |
923 |
} |
924 |
if (e == null || ex != null) |
925 |
dst.internalComplete(null, ex); |
926 |
} |
927 |
} |
928 |
private static final long serialVersionUID = 5232453952276885070L; |
929 |
} |
930 |
|
931 |
static final class AndCompletion extends Completion { |
932 |
final CompletableFuture<?> src; |
933 |
final CompletableFuture<?> snd; |
934 |
final CompletableFuture<Void> dst; |
935 |
AndCompletion(CompletableFuture<?> src, |
936 |
CompletableFuture<?> snd, |
937 |
CompletableFuture<Void> dst) { |
938 |
this.src = src; this.snd = snd; this.dst = dst; |
939 |
} |
940 |
public final void run() { |
941 |
final CompletableFuture<?> a; |
942 |
final CompletableFuture<?> b; |
943 |
final CompletableFuture<Void> dst; |
944 |
Object r, s; Throwable ex; |
945 |
if ((dst = this.dst) != null && |
946 |
(a = this.src) != null && |
947 |
(r = a.result) != null && |
948 |
(b = this.snd) != null && |
949 |
(s = b.result) != null && |
950 |
compareAndSet(0, 1)) { |
951 |
if (r instanceof AltResult) |
952 |
ex = ((AltResult)r).ex; |
953 |
else |
954 |
ex = null; |
955 |
if (ex == null && (s instanceof AltResult)) |
956 |
ex = ((AltResult)s).ex; |
957 |
dst.internalComplete(null, ex); |
958 |
} |
959 |
} |
960 |
private static final long serialVersionUID = 5232453952276885070L; |
961 |
} |
962 |
|
963 |
static final class OrApplyCompletion<T,U> extends Completion { |
964 |
final CompletableFuture<? extends T> src; |
965 |
final CompletableFuture<? extends T> snd; |
966 |
final Function<? super T,? extends U> fn; |
967 |
final CompletableFuture<U> dst; |
968 |
final Executor executor; |
969 |
OrApplyCompletion(CompletableFuture<? extends T> src, |
970 |
CompletableFuture<? extends T> snd, |
971 |
Function<? super T,? extends U> fn, |
972 |
CompletableFuture<U> dst, Executor executor) { |
973 |
this.src = src; this.snd = snd; |
974 |
this.fn = fn; this.dst = dst; |
975 |
this.executor = executor; |
976 |
} |
977 |
public final void run() { |
978 |
final CompletableFuture<? extends T> a; |
979 |
final CompletableFuture<? extends T> b; |
980 |
final Function<? super T,? extends U> fn; |
981 |
final CompletableFuture<U> dst; |
982 |
Object r; T t; Throwable ex; |
983 |
if ((dst = this.dst) != null && |
984 |
(fn = this.fn) != null && |
985 |
(((a = this.src) != null && (r = a.result) != null) || |
986 |
((b = this.snd) != null && (r = b.result) != null)) && |
987 |
compareAndSet(0, 1)) { |
988 |
if (r instanceof AltResult) { |
989 |
ex = ((AltResult)r).ex; |
990 |
t = null; |
991 |
} |
992 |
else { |
993 |
ex = null; |
994 |
@SuppressWarnings("unchecked") T tr = (T) r; |
995 |
t = tr; |
996 |
} |
997 |
Executor e = executor; |
998 |
U u = null; |
999 |
if (ex == null) { |
1000 |
try { |
1001 |
if (e != null) |
1002 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
1003 |
else |
1004 |
u = fn.apply(t); |
1005 |
} catch (Throwable rex) { |
1006 |
ex = rex; |
1007 |
} |
1008 |
} |
1009 |
if (e == null || ex != null) |
1010 |
dst.internalComplete(u, ex); |
1011 |
} |
1012 |
} |
1013 |
private static final long serialVersionUID = 5232453952276885070L; |
1014 |
} |
1015 |
|
1016 |
static final class OrAcceptCompletion<T> extends Completion { |
1017 |
final CompletableFuture<? extends T> src; |
1018 |
final CompletableFuture<? extends T> snd; |
1019 |
final Consumer<? super T> fn; |
1020 |
final CompletableFuture<Void> dst; |
1021 |
final Executor executor; |
1022 |
OrAcceptCompletion(CompletableFuture<? extends T> src, |
1023 |
CompletableFuture<? extends T> snd, |
1024 |
Consumer<? super T> fn, |
1025 |
CompletableFuture<Void> dst, Executor executor) { |
1026 |
this.src = src; this.snd = snd; |
1027 |
this.fn = fn; this.dst = dst; |
1028 |
this.executor = executor; |
1029 |
} |
1030 |
public final void run() { |
1031 |
final CompletableFuture<? extends T> a; |
1032 |
final CompletableFuture<? extends T> b; |
1033 |
final Consumer<? super T> fn; |
1034 |
final CompletableFuture<Void> dst; |
1035 |
Object r; T t; Throwable ex; |
1036 |
if ((dst = this.dst) != null && |
1037 |
(fn = this.fn) != null && |
1038 |
(((a = this.src) != null && (r = a.result) != null) || |
1039 |
((b = this.snd) != null && (r = b.result) != null)) && |
1040 |
compareAndSet(0, 1)) { |
1041 |
if (r instanceof AltResult) { |
1042 |
ex = ((AltResult)r).ex; |
1043 |
t = null; |
1044 |
} |
1045 |
else { |
1046 |
ex = null; |
1047 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1048 |
t = tr; |
1049 |
} |
1050 |
Executor e = executor; |
1051 |
if (ex == null) { |
1052 |
try { |
1053 |
if (e != null) |
1054 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
1055 |
else |
1056 |
fn.accept(t); |
1057 |
} catch (Throwable rex) { |
1058 |
ex = rex; |
1059 |
} |
1060 |
} |
1061 |
if (e == null || ex != null) |
1062 |
dst.internalComplete(null, ex); |
1063 |
} |
1064 |
} |
1065 |
private static final long serialVersionUID = 5232453952276885070L; |
1066 |
} |
1067 |
|
1068 |
static final class OrRunCompletion<T> extends Completion { |
1069 |
final CompletableFuture<? extends T> src; |
1070 |
final CompletableFuture<?> snd; |
1071 |
final Runnable fn; |
1072 |
final CompletableFuture<Void> dst; |
1073 |
final Executor executor; |
1074 |
OrRunCompletion(CompletableFuture<? extends T> src, |
1075 |
CompletableFuture<?> snd, |
1076 |
Runnable fn, |
1077 |
CompletableFuture<Void> dst, Executor executor) { |
1078 |
this.src = src; this.snd = snd; |
1079 |
this.fn = fn; this.dst = dst; |
1080 |
this.executor = executor; |
1081 |
} |
1082 |
public final void run() { |
1083 |
final CompletableFuture<? extends T> a; |
1084 |
final CompletableFuture<?> b; |
1085 |
final Runnable fn; |
1086 |
final CompletableFuture<Void> dst; |
1087 |
Object r; Throwable ex; |
1088 |
if ((dst = this.dst) != null && |
1089 |
(fn = this.fn) != null && |
1090 |
(((a = this.src) != null && (r = a.result) != null) || |
1091 |
((b = this.snd) != null && (r = b.result) != null)) && |
1092 |
compareAndSet(0, 1)) { |
1093 |
if (r instanceof AltResult) |
1094 |
ex = ((AltResult)r).ex; |
1095 |
else |
1096 |
ex = null; |
1097 |
Executor e = executor; |
1098 |
if (ex == null) { |
1099 |
try { |
1100 |
if (e != null) |
1101 |
e.execute(new AsyncRun(fn, dst)); |
1102 |
else |
1103 |
fn.run(); |
1104 |
} catch (Throwable rex) { |
1105 |
ex = rex; |
1106 |
} |
1107 |
} |
1108 |
if (e == null || ex != null) |
1109 |
dst.internalComplete(null, ex); |
1110 |
} |
1111 |
} |
1112 |
private static final long serialVersionUID = 5232453952276885070L; |
1113 |
} |
1114 |
|
1115 |
static final class OrCompletion extends Completion { |
1116 |
final CompletableFuture<?> src; |
1117 |
final CompletableFuture<?> snd; |
1118 |
final CompletableFuture<?> dst; |
1119 |
OrCompletion(CompletableFuture<?> src, |
1120 |
CompletableFuture<?> snd, |
1121 |
CompletableFuture<?> dst) { |
1122 |
this.src = src; this.snd = snd; this.dst = dst; |
1123 |
} |
1124 |
public final void run() { |
1125 |
final CompletableFuture<?> a; |
1126 |
final CompletableFuture<?> b; |
1127 |
final CompletableFuture<?> dst; |
1128 |
Object r, t; Throwable ex; |
1129 |
if ((dst = this.dst) != null && |
1130 |
(((a = this.src) != null && (r = a.result) != null) || |
1131 |
((b = this.snd) != null && (r = b.result) != null)) && |
1132 |
compareAndSet(0, 1)) { |
1133 |
if (r instanceof AltResult) { |
1134 |
ex = ((AltResult)r).ex; |
1135 |
t = null; |
1136 |
} |
1137 |
else { |
1138 |
ex = null; |
1139 |
t = r; |
1140 |
} |
1141 |
dst.internalComplete(t, ex); |
1142 |
} |
1143 |
} |
1144 |
private static final long serialVersionUID = 5232453952276885070L; |
1145 |
} |
1146 |
|
1147 |
static final class ExceptionCompletion<T> extends Completion { |
1148 |
final CompletableFuture<? extends T> src; |
1149 |
final Function<? super Throwable, ? extends T> fn; |
1150 |
final CompletableFuture<T> dst; |
1151 |
ExceptionCompletion(CompletableFuture<? extends T> src, |
1152 |
Function<? super Throwable, ? extends T> fn, |
1153 |
CompletableFuture<T> dst) { |
1154 |
this.src = src; this.fn = fn; this.dst = dst; |
1155 |
} |
1156 |
public final void run() { |
1157 |
final CompletableFuture<? extends T> a; |
1158 |
final Function<? super Throwable, ? extends T> fn; |
1159 |
final CompletableFuture<T> dst; |
1160 |
Object r; T t = null; Throwable ex, dx = null; |
1161 |
if ((dst = this.dst) != null && |
1162 |
(fn = this.fn) != null && |
1163 |
(a = this.src) != null && |
1164 |
(r = a.result) != null && |
1165 |
compareAndSet(0, 1)) { |
1166 |
if ((r instanceof AltResult) && |
1167 |
(ex = ((AltResult)r).ex) != null) { |
1168 |
try { |
1169 |
t = fn.apply(ex); |
1170 |
} catch (Throwable rex) { |
1171 |
dx = rex; |
1172 |
} |
1173 |
} |
1174 |
else { |
1175 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1176 |
t = tr; |
1177 |
} |
1178 |
dst.internalComplete(t, dx); |
1179 |
} |
1180 |
} |
1181 |
private static final long serialVersionUID = 5232453952276885070L; |
1182 |
} |
1183 |
|
1184 |
static final class ThenCopy extends Completion { |
1185 |
final CompletableFuture<?> src; |
1186 |
final CompletableFuture<?> dst; |
1187 |
ThenCopy(CompletableFuture<?> src, |
1188 |
CompletableFuture<?> dst) { |
1189 |
this.src = src; this.dst = dst; |
1190 |
} |
1191 |
public final void run() { |
1192 |
final CompletableFuture<?> a; |
1193 |
final CompletableFuture<?> dst; |
1194 |
Object r; Object t; Throwable ex; |
1195 |
if ((dst = this.dst) != null && |
1196 |
(a = this.src) != null && |
1197 |
(r = a.result) != null && |
1198 |
compareAndSet(0, 1)) { |
1199 |
if (r instanceof AltResult) { |
1200 |
ex = ((AltResult)r).ex; |
1201 |
t = null; |
1202 |
} |
1203 |
else { |
1204 |
ex = null; |
1205 |
t = r; |
1206 |
} |
1207 |
dst.internalComplete(t, ex); |
1208 |
} |
1209 |
} |
1210 |
private static final long serialVersionUID = 5232453952276885070L; |
1211 |
} |
1212 |
|
1213 |
static final class HandleCompletion<T,U> extends Completion { |
1214 |
final CompletableFuture<? extends T> src; |
1215 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1216 |
final CompletableFuture<U> dst; |
1217 |
HandleCompletion(CompletableFuture<? extends T> src, |
1218 |
BiFunction<? super T, Throwable, ? extends U> fn, |
1219 |
final CompletableFuture<U> dst) { |
1220 |
this.src = src; this.fn = fn; this.dst = dst; |
1221 |
} |
1222 |
public final void run() { |
1223 |
final CompletableFuture<? extends T> a; |
1224 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1225 |
final CompletableFuture<U> dst; |
1226 |
Object r; T t; Throwable ex; |
1227 |
if ((dst = this.dst) != null && |
1228 |
(fn = this.fn) != null && |
1229 |
(a = this.src) != null && |
1230 |
(r = a.result) != null && |
1231 |
compareAndSet(0, 1)) { |
1232 |
if (r instanceof AltResult) { |
1233 |
ex = ((AltResult)r).ex; |
1234 |
t = null; |
1235 |
} |
1236 |
else { |
1237 |
ex = null; |
1238 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1239 |
t = tr; |
1240 |
} |
1241 |
U u = null; Throwable dx = null; |
1242 |
try { |
1243 |
u = fn.apply(t, ex); |
1244 |
} catch (Throwable rex) { |
1245 |
dx = rex; |
1246 |
} |
1247 |
dst.internalComplete(u, dx); |
1248 |
} |
1249 |
} |
1250 |
private static final long serialVersionUID = 5232453952276885070L; |
1251 |
} |
1252 |
|
1253 |
static final class ComposeCompletion<T,U> extends Completion { |
1254 |
final CompletableFuture<? extends T> src; |
1255 |
final Function<? super T, CompletableFuture<U>> fn; |
1256 |
final CompletableFuture<U> dst; |
1257 |
final Executor executor; |
1258 |
ComposeCompletion(CompletableFuture<? extends T> src, |
1259 |
Function<? super T, CompletableFuture<U>> fn, |
1260 |
final CompletableFuture<U> dst, Executor executor) { |
1261 |
this.src = src; this.fn = fn; this.dst = dst; |
1262 |
this.executor = executor; |
1263 |
} |
1264 |
public final void run() { |
1265 |
final CompletableFuture<? extends T> a; |
1266 |
final Function<? super T, CompletableFuture<U>> fn; |
1267 |
final CompletableFuture<U> dst; |
1268 |
Object r; T t; Throwable ex; Executor e; |
1269 |
if ((dst = this.dst) != null && |
1270 |
(fn = this.fn) != null && |
1271 |
(a = this.src) != null && |
1272 |
(r = a.result) != null && |
1273 |
compareAndSet(0, 1)) { |
1274 |
if (r instanceof AltResult) { |
1275 |
ex = ((AltResult)r).ex; |
1276 |
t = null; |
1277 |
} |
1278 |
else { |
1279 |
ex = null; |
1280 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1281 |
t = tr; |
1282 |
} |
1283 |
CompletableFuture<U> c = null; |
1284 |
U u = null; |
1285 |
boolean complete = false; |
1286 |
if (ex == null) { |
1287 |
if ((e = executor) != null) |
1288 |
e.execute(new AsyncCompose<T,U>(t, fn, dst)); |
1289 |
else { |
1290 |
try { |
1291 |
if ((c = fn.apply(t)) == null) |
1292 |
ex = new NullPointerException(); |
1293 |
} catch (Throwable rex) { |
1294 |
ex = rex; |
1295 |
} |
1296 |
} |
1297 |
} |
1298 |
if (c != null) { |
1299 |
ThenCopy d = null; |
1300 |
Object s; |
1301 |
if ((s = c.result) == null) { |
1302 |
CompletionNode p = new CompletionNode |
1303 |
(d = new ThenCopy(c, dst)); |
1304 |
while ((s = c.result) == null) { |
1305 |
if (UNSAFE.compareAndSwapObject |
1306 |
(c, COMPLETIONS, p.next = c.completions, p)) |
1307 |
break; |
1308 |
} |
1309 |
} |
1310 |
if (s != null && (d == null || d.compareAndSet(0, 1))) { |
1311 |
complete = true; |
1312 |
if (s instanceof AltResult) { |
1313 |
ex = ((AltResult)s).ex; // no rewrap |
1314 |
u = null; |
1315 |
} |
1316 |
else { |
1317 |
@SuppressWarnings("unchecked") U us = (U) s; |
1318 |
u = us; |
1319 |
} |
1320 |
} |
1321 |
} |
1322 |
if (complete || ex != null) |
1323 |
dst.internalComplete(u, ex); |
1324 |
if (c != null) |
1325 |
c.helpPostComplete(); |
1326 |
} |
1327 |
} |
1328 |
private static final long serialVersionUID = 5232453952276885070L; |
1329 |
} |
1330 |
|
1331 |
// public methods |
1332 |
|
1333 |
/** |
1334 |
* Creates a new incomplete CompletableFuture. |
1335 |
*/ |
1336 |
public CompletableFuture() { |
1337 |
} |
1338 |
|
1339 |
/** |
1340 |
* Asynchronously executes in the {@link |
1341 |
* ForkJoinPool#commonPool()}, a task that completes the returned |
1342 |
* CompletableFuture with the result of the given Supplier. |
1343 |
* |
1344 |
* @param supplier a function returning the value to be used |
1345 |
* to complete the returned CompletableFuture |
1346 |
* @return the CompletableFuture |
1347 |
*/ |
1348 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier) { |
1349 |
if (supplier == null) throw new NullPointerException(); |
1350 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
1351 |
ForkJoinPool.commonPool(). |
1352 |
execute((ForkJoinTask<?>)new AsyncSupply<U>(supplier, f)); |
1353 |
return f; |
1354 |
} |
1355 |
|
1356 |
/** |
1357 |
* Asynchronously executes using the given executor, a task that |
1358 |
* completes the returned CompletableFuture with the result of the |
1359 |
* given Supplier. |
1360 |
* |
1361 |
* @param supplier a function returning the value to be used |
1362 |
* to complete the returned CompletableFuture |
1363 |
* @param executor the executor to use for asynchronous execution |
1364 |
* @return the CompletableFuture |
1365 |
*/ |
1366 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier, |
1367 |
Executor executor) { |
1368 |
if (executor == null || supplier == null) |
1369 |
throw new NullPointerException(); |
1370 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
1371 |
executor.execute(new AsyncSupply<U>(supplier, f)); |
1372 |
return f; |
1373 |
} |
1374 |
|
1375 |
/** |
1376 |
* Asynchronously executes in the {@link |
1377 |
* ForkJoinPool#commonPool()} a task that runs the given action, |
1378 |
* and then completes the returned CompletableFuture. |
1379 |
* |
1380 |
* @param runnable the action to run before completing the |
1381 |
* returned CompletableFuture |
1382 |
* @return the CompletableFuture |
1383 |
*/ |
1384 |
public static CompletableFuture<Void> runAsync(Runnable runnable) { |
1385 |
if (runnable == null) throw new NullPointerException(); |
1386 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
1387 |
ForkJoinPool.commonPool(). |
1388 |
execute((ForkJoinTask<?>)new AsyncRun(runnable, f)); |
1389 |
return f; |
1390 |
} |
1391 |
|
1392 |
/** |
1393 |
* Asynchronously executes using the given executor, a task that |
1394 |
* runs the given action, and then completes the returned |
1395 |
* CompletableFuture. |
1396 |
* |
1397 |
* @param runnable the action to run before completing the |
1398 |
* returned CompletableFuture |
1399 |
* @param executor the executor to use for asynchronous execution |
1400 |
* @return the CompletableFuture |
1401 |
*/ |
1402 |
public static CompletableFuture<Void> runAsync(Runnable runnable, |
1403 |
Executor executor) { |
1404 |
if (executor == null || runnable == null) |
1405 |
throw new NullPointerException(); |
1406 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
1407 |
executor.execute(new AsyncRun(runnable, f)); |
1408 |
return f; |
1409 |
} |
1410 |
|
1411 |
/** |
1412 |
* Returns {@code true} if completed in any fashion: normally, |
1413 |
* exceptionally, or via cancellation. |
1414 |
* |
1415 |
* @return {@code true} if completed |
1416 |
*/ |
1417 |
public boolean isDone() { |
1418 |
return result != null; |
1419 |
} |
1420 |
|
1421 |
/** |
1422 |
* Waits if necessary for this future to complete, and then |
1423 |
* returns its result. |
1424 |
* |
1425 |
* @return the result value |
1426 |
* @throws CancellationException if this future was cancelled |
1427 |
* @throws ExecutionException if this future completed exceptionally |
1428 |
* @throws InterruptedException if the current thread was interrupted |
1429 |
* while waiting |
1430 |
*/ |
1431 |
public T get() throws InterruptedException, ExecutionException { |
1432 |
Object r; Throwable ex, cause; |
1433 |
if ((r = result) == null && (r = waitingGet(true)) == null) |
1434 |
throw new InterruptedException(); |
1435 |
if (!(r instanceof AltResult)) { |
1436 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1437 |
return tr; |
1438 |
} |
1439 |
if ((ex = ((AltResult)r).ex) == null) |
1440 |
return null; |
1441 |
if (ex instanceof CancellationException) |
1442 |
throw (CancellationException)ex; |
1443 |
if ((ex instanceof CompletionException) && |
1444 |
(cause = ex.getCause()) != null) |
1445 |
ex = cause; |
1446 |
throw new ExecutionException(ex); |
1447 |
} |
1448 |
|
1449 |
/** |
1450 |
* Waits if necessary for at most the given time for this future |
1451 |
* to complete, and then returns its result, if available. |
1452 |
* |
1453 |
* @param timeout the maximum time to wait |
1454 |
* @param unit the time unit of the timeout argument |
1455 |
* @return the result value |
1456 |
* @throws CancellationException if this future was cancelled |
1457 |
* @throws ExecutionException if this future completed exceptionally |
1458 |
* @throws InterruptedException if the current thread was interrupted |
1459 |
* while waiting |
1460 |
* @throws TimeoutException if the wait timed out |
1461 |
*/ |
1462 |
public T get(long timeout, TimeUnit unit) |
1463 |
throws InterruptedException, ExecutionException, TimeoutException { |
1464 |
Object r; Throwable ex, cause; |
1465 |
long nanos = unit.toNanos(timeout); |
1466 |
if (Thread.interrupted()) |
1467 |
throw new InterruptedException(); |
1468 |
if ((r = result) == null) |
1469 |
r = timedAwaitDone(nanos); |
1470 |
if (!(r instanceof AltResult)) { |
1471 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1472 |
return tr; |
1473 |
} |
1474 |
if ((ex = ((AltResult)r).ex) == null) |
1475 |
return null; |
1476 |
if (ex instanceof CancellationException) |
1477 |
throw (CancellationException)ex; |
1478 |
if ((ex instanceof CompletionException) && |
1479 |
(cause = ex.getCause()) != null) |
1480 |
ex = cause; |
1481 |
throw new ExecutionException(ex); |
1482 |
} |
1483 |
|
1484 |
/** |
1485 |
* Returns the result value when complete, or throws an |
1486 |
* (unchecked) exception if completed exceptionally. To better |
1487 |
* conform with the use of common functional forms, if a |
1488 |
* computation involved in the completion of this |
1489 |
* CompletableFuture threw an exception, this method throws an |
1490 |
* (unchecked) {@link CompletionException} with the underlying |
1491 |
* exception as its cause. |
1492 |
* |
1493 |
* @return the result value |
1494 |
* @throws CancellationException if the computation was cancelled |
1495 |
* @throws CompletionException if this future completed |
1496 |
* exceptionally or a completion computation threw an exception |
1497 |
*/ |
1498 |
public T join() { |
1499 |
Object r; Throwable ex; |
1500 |
if ((r = result) == null) |
1501 |
r = waitingGet(false); |
1502 |
if (!(r instanceof AltResult)) { |
1503 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1504 |
return tr; |
1505 |
} |
1506 |
if ((ex = ((AltResult)r).ex) == null) |
1507 |
return null; |
1508 |
if (ex instanceof CancellationException) |
1509 |
throw (CancellationException)ex; |
1510 |
if (ex instanceof CompletionException) |
1511 |
throw (CompletionException)ex; |
1512 |
throw new CompletionException(ex); |
1513 |
} |
1514 |
|
1515 |
/** |
1516 |
* Returns the result value (or throws any encountered exception) |
1517 |
* if completed, else returns the given valueIfAbsent. |
1518 |
* |
1519 |
* @param valueIfAbsent the value to return if not completed |
1520 |
* @return the result value, if completed, else the given valueIfAbsent |
1521 |
* @throws CancellationException if the computation was cancelled |
1522 |
* @throws CompletionException if this future completed |
1523 |
* exceptionally or a completion computation threw an exception |
1524 |
*/ |
1525 |
public T getNow(T valueIfAbsent) { |
1526 |
Object r; Throwable ex; |
1527 |
if ((r = result) == null) |
1528 |
return valueIfAbsent; |
1529 |
if (!(r instanceof AltResult)) { |
1530 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1531 |
return tr; |
1532 |
} |
1533 |
if ((ex = ((AltResult)r).ex) == null) |
1534 |
return null; |
1535 |
if (ex instanceof CancellationException) |
1536 |
throw (CancellationException)ex; |
1537 |
if (ex instanceof CompletionException) |
1538 |
throw (CompletionException)ex; |
1539 |
throw new CompletionException(ex); |
1540 |
} |
1541 |
|
1542 |
/** |
1543 |
* If not already completed, sets the value returned by {@link |
1544 |
* #get()} and related methods to the given value. |
1545 |
* |
1546 |
* @param value the result value |
1547 |
* @return {@code true} if this invocation caused this CompletableFuture |
1548 |
* to transition to a completed state, else {@code false} |
1549 |
*/ |
1550 |
public boolean complete(T value) { |
1551 |
boolean triggered = result == null && |
1552 |
UNSAFE.compareAndSwapObject(this, RESULT, null, |
1553 |
value == null ? NIL : value); |
1554 |
postComplete(); |
1555 |
return triggered; |
1556 |
} |
1557 |
|
1558 |
/** |
1559 |
* If not already completed, causes invocations of {@link #get()} |
1560 |
* and related methods to throw the given exception. |
1561 |
* |
1562 |
* @param ex the exception |
1563 |
* @return {@code true} if this invocation caused this CompletableFuture |
1564 |
* to transition to a completed state, else {@code false} |
1565 |
*/ |
1566 |
public boolean completeExceptionally(Throwable ex) { |
1567 |
if (ex == null) throw new NullPointerException(); |
1568 |
boolean triggered = result == null && |
1569 |
UNSAFE.compareAndSwapObject(this, RESULT, null, new AltResult(ex)); |
1570 |
postComplete(); |
1571 |
return triggered; |
1572 |
} |
1573 |
|
1574 |
/** |
1575 |
* Creates and returns a CompletableFuture that is completed with |
1576 |
* the result of the given function of this CompletableFuture. |
1577 |
* If this CompletableFuture completes exceptionally, |
1578 |
* then the returned CompletableFuture also does so, |
1579 |
* with a CompletionException holding this exception as |
1580 |
* its cause. |
1581 |
* |
1582 |
* @param fn the function to use to compute the value of |
1583 |
* the returned CompletableFuture |
1584 |
* @return the new CompletableFuture |
1585 |
*/ |
1586 |
public <U> CompletableFuture<U> thenApply(Function<? super T,? extends U> fn) { |
1587 |
return doThenApply(fn, null); |
1588 |
} |
1589 |
|
1590 |
/** |
1591 |
* Creates and returns a CompletableFuture that is asynchronously |
1592 |
* completed using the {@link ForkJoinPool#commonPool()} with the |
1593 |
* result of the given function of this CompletableFuture. If |
1594 |
* this CompletableFuture completes exceptionally, then the |
1595 |
* returned CompletableFuture also does so, with a |
1596 |
* CompletionException holding this exception as its cause. |
1597 |
* |
1598 |
* @param fn the function to use to compute the value of |
1599 |
* the returned CompletableFuture |
1600 |
* @return the new CompletableFuture |
1601 |
*/ |
1602 |
public <U> CompletableFuture<U> thenApplyAsync |
1603 |
(Function<? super T,? extends U> fn) { |
1604 |
return doThenApply(fn, ForkJoinPool.commonPool()); |
1605 |
} |
1606 |
|
1607 |
/** |
1608 |
* Creates and returns a CompletableFuture that is asynchronously |
1609 |
* completed using the given executor with the result of the given |
1610 |
* function of this CompletableFuture. If this CompletableFuture |
1611 |
* completes exceptionally, then the returned CompletableFuture |
1612 |
* also does so, with a CompletionException holding this exception as |
1613 |
* its cause. |
1614 |
* |
1615 |
* @param fn the function to use to compute the value of |
1616 |
* the returned CompletableFuture |
1617 |
* @param executor the executor to use for asynchronous execution |
1618 |
* @return the new CompletableFuture |
1619 |
*/ |
1620 |
public <U> CompletableFuture<U> thenApplyAsync |
1621 |
(Function<? super T,? extends U> fn, |
1622 |
Executor executor) { |
1623 |
if (executor == null) throw new NullPointerException(); |
1624 |
return doThenApply(fn, executor); |
1625 |
} |
1626 |
|
1627 |
private <U> CompletableFuture<U> doThenApply |
1628 |
(Function<? super T,? extends U> fn, |
1629 |
Executor e) { |
1630 |
if (fn == null) throw new NullPointerException(); |
1631 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
1632 |
ApplyCompletion<T,U> d = null; |
1633 |
Object r; |
1634 |
if ((r = result) == null) { |
1635 |
CompletionNode p = new CompletionNode |
1636 |
(d = new ApplyCompletion<T,U>(this, fn, dst, e)); |
1637 |
while ((r = result) == null) { |
1638 |
if (UNSAFE.compareAndSwapObject |
1639 |
(this, COMPLETIONS, p.next = completions, p)) |
1640 |
break; |
1641 |
} |
1642 |
} |
1643 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1644 |
T t; Throwable ex; |
1645 |
if (r instanceof AltResult) { |
1646 |
ex = ((AltResult)r).ex; |
1647 |
t = null; |
1648 |
} |
1649 |
else { |
1650 |
ex = null; |
1651 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1652 |
t = tr; |
1653 |
} |
1654 |
U u = null; |
1655 |
if (ex == null) { |
1656 |
try { |
1657 |
if (e != null) |
1658 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
1659 |
else |
1660 |
u = fn.apply(t); |
1661 |
} catch (Throwable rex) { |
1662 |
ex = rex; |
1663 |
} |
1664 |
} |
1665 |
if (e == null || ex != null) |
1666 |
dst.internalComplete(u, ex); |
1667 |
} |
1668 |
helpPostComplete(); |
1669 |
return dst; |
1670 |
} |
1671 |
|
1672 |
/** |
1673 |
* Creates and returns a CompletableFuture that is completed after |
1674 |
* performing the given action with this CompletableFuture's |
1675 |
* result when it completes. If this CompletableFuture |
1676 |
* completes exceptionally, then the returned CompletableFuture |
1677 |
* also does so, with a CompletionException holding this exception as |
1678 |
* its cause. |
1679 |
* |
1680 |
* @param block the action to perform before completing the |
1681 |
* returned CompletableFuture |
1682 |
* @return the new CompletableFuture |
1683 |
*/ |
1684 |
public CompletableFuture<Void> thenAccept(Consumer<? super T> block) { |
1685 |
return doThenAccept(block, null); |
1686 |
} |
1687 |
|
1688 |
/** |
1689 |
* Creates and returns a CompletableFuture that is asynchronously |
1690 |
* completed using the {@link ForkJoinPool#commonPool()} with this |
1691 |
* CompletableFuture's result when it completes. If this |
1692 |
* CompletableFuture completes exceptionally, then the returned |
1693 |
* CompletableFuture also does so, with a CompletionException holding |
1694 |
* this exception as its cause. |
1695 |
* |
1696 |
* @param block the action to perform before completing the |
1697 |
* returned CompletableFuture |
1698 |
* @return the new CompletableFuture |
1699 |
*/ |
1700 |
public CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> block) { |
1701 |
return doThenAccept(block, ForkJoinPool.commonPool()); |
1702 |
} |
1703 |
|
1704 |
/** |
1705 |
* Creates and returns a CompletableFuture that is asynchronously |
1706 |
* completed using the given executor with this |
1707 |
* CompletableFuture's result when it completes. If this |
1708 |
* CompletableFuture completes exceptionally, then the returned |
1709 |
* CompletableFuture also does so, with a CompletionException holding |
1710 |
* this exception as its cause. |
1711 |
* |
1712 |
* @param block the action to perform before completing the |
1713 |
* returned CompletableFuture |
1714 |
* @param executor the executor to use for asynchronous execution |
1715 |
* @return the new CompletableFuture |
1716 |
*/ |
1717 |
public CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> block, |
1718 |
Executor executor) { |
1719 |
if (executor == null) throw new NullPointerException(); |
1720 |
return doThenAccept(block, executor); |
1721 |
} |
1722 |
|
1723 |
private CompletableFuture<Void> doThenAccept(Consumer<? super T> fn, |
1724 |
Executor e) { |
1725 |
if (fn == null) throw new NullPointerException(); |
1726 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1727 |
AcceptCompletion<T> d = null; |
1728 |
Object r; |
1729 |
if ((r = result) == null) { |
1730 |
CompletionNode p = new CompletionNode |
1731 |
(d = new AcceptCompletion<T>(this, fn, dst, e)); |
1732 |
while ((r = result) == null) { |
1733 |
if (UNSAFE.compareAndSwapObject |
1734 |
(this, COMPLETIONS, p.next = completions, p)) |
1735 |
break; |
1736 |
} |
1737 |
} |
1738 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1739 |
T t; Throwable ex; |
1740 |
if (r instanceof AltResult) { |
1741 |
ex = ((AltResult)r).ex; |
1742 |
t = null; |
1743 |
} |
1744 |
else { |
1745 |
ex = null; |
1746 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1747 |
t = tr; |
1748 |
} |
1749 |
if (ex == null) { |
1750 |
try { |
1751 |
if (e != null) |
1752 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
1753 |
else |
1754 |
fn.accept(t); |
1755 |
} catch (Throwable rex) { |
1756 |
ex = rex; |
1757 |
} |
1758 |
} |
1759 |
if (e == null || ex != null) |
1760 |
dst.internalComplete(null, ex); |
1761 |
} |
1762 |
helpPostComplete(); |
1763 |
return dst; |
1764 |
} |
1765 |
|
1766 |
/** |
1767 |
* Creates and returns a CompletableFuture that is completed after |
1768 |
* performing the given action when this CompletableFuture |
1769 |
* completes. If this CompletableFuture completes exceptionally, |
1770 |
* then the returned CompletableFuture also does so, with a |
1771 |
* CompletionException holding this exception as its cause. |
1772 |
* |
1773 |
* @param action the action to perform before completing the |
1774 |
* returned CompletableFuture |
1775 |
* @return the new CompletableFuture |
1776 |
*/ |
1777 |
public CompletableFuture<Void> thenRun(Runnable action) { |
1778 |
return doThenRun(action, null); |
1779 |
} |
1780 |
|
1781 |
/** |
1782 |
* Creates and returns a CompletableFuture that is asynchronously |
1783 |
* completed using the {@link ForkJoinPool#commonPool()} after |
1784 |
* performing the given action when this CompletableFuture |
1785 |
* completes. If this CompletableFuture completes exceptionally, |
1786 |
* then the returned CompletableFuture also does so, with a |
1787 |
* CompletionException holding this exception as its cause. |
1788 |
* |
1789 |
* @param action the action to perform before completing the |
1790 |
* returned CompletableFuture |
1791 |
* @return the new CompletableFuture |
1792 |
*/ |
1793 |
public CompletableFuture<Void> thenRunAsync(Runnable action) { |
1794 |
return doThenRun(action, ForkJoinPool.commonPool()); |
1795 |
} |
1796 |
|
1797 |
/** |
1798 |
* Creates and returns a CompletableFuture that is asynchronously |
1799 |
* completed using the given executor after performing the given |
1800 |
* action when this CompletableFuture completes. If this |
1801 |
* CompletableFuture completes exceptionally, then the returned |
1802 |
* CompletableFuture also does so, with a CompletionException holding |
1803 |
* this exception as its cause. |
1804 |
* |
1805 |
* @param action the action to perform before completing the |
1806 |
* returned CompletableFuture |
1807 |
* @param executor the executor to use for asynchronous execution |
1808 |
* @return the new CompletableFuture |
1809 |
*/ |
1810 |
public CompletableFuture<Void> thenRunAsync(Runnable action, |
1811 |
Executor executor) { |
1812 |
if (executor == null) throw new NullPointerException(); |
1813 |
return doThenRun(action, executor); |
1814 |
} |
1815 |
|
1816 |
private CompletableFuture<Void> doThenRun(Runnable action, |
1817 |
Executor e) { |
1818 |
if (action == null) throw new NullPointerException(); |
1819 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1820 |
RunCompletion<T> d = null; |
1821 |
Object r; |
1822 |
if ((r = result) == null) { |
1823 |
CompletionNode p = new CompletionNode |
1824 |
(d = new RunCompletion<T>(this, action, dst, e)); |
1825 |
while ((r = result) == null) { |
1826 |
if (UNSAFE.compareAndSwapObject |
1827 |
(this, COMPLETIONS, p.next = completions, p)) |
1828 |
break; |
1829 |
} |
1830 |
} |
1831 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1832 |
Throwable ex; |
1833 |
if (r instanceof AltResult) |
1834 |
ex = ((AltResult)r).ex; |
1835 |
else |
1836 |
ex = null; |
1837 |
if (ex == null) { |
1838 |
try { |
1839 |
if (e != null) |
1840 |
e.execute(new AsyncRun(action, dst)); |
1841 |
else |
1842 |
action.run(); |
1843 |
} catch (Throwable rex) { |
1844 |
ex = rex; |
1845 |
} |
1846 |
} |
1847 |
if (e == null || ex != null) |
1848 |
dst.internalComplete(null, ex); |
1849 |
} |
1850 |
helpPostComplete(); |
1851 |
return dst; |
1852 |
} |
1853 |
|
1854 |
/** |
1855 |
* Creates and returns a CompletableFuture that is completed with |
1856 |
* the result of the given function of this and the other given |
1857 |
* CompletableFuture's results when both complete. If this or |
1858 |
* the other CompletableFuture complete exceptionally, then the |
1859 |
* returned CompletableFuture also does so, with a |
1860 |
* CompletionException holding the exception as its cause. |
1861 |
* |
1862 |
* @param other the other CompletableFuture |
1863 |
* @param fn the function to use to compute the value of |
1864 |
* the returned CompletableFuture |
1865 |
* @return the new CompletableFuture |
1866 |
*/ |
1867 |
public <U,V> CompletableFuture<V> thenCombine |
1868 |
(CompletableFuture<? extends U> other, |
1869 |
BiFunction<? super T,? super U,? extends V> fn) { |
1870 |
return doThenBiApply(other, fn, null); |
1871 |
} |
1872 |
|
1873 |
/** |
1874 |
* Creates and returns a CompletableFuture that is asynchronously |
1875 |
* completed using the {@link ForkJoinPool#commonPool()} with |
1876 |
* the result of the given function of this and the other given |
1877 |
* CompletableFuture's results when both complete. If this or |
1878 |
* the other CompletableFuture complete exceptionally, then the |
1879 |
* returned CompletableFuture also does so, with a |
1880 |
* CompletionException holding the exception as its cause. |
1881 |
* |
1882 |
* @param other the other CompletableFuture |
1883 |
* @param fn the function to use to compute the value of |
1884 |
* the returned CompletableFuture |
1885 |
* @return the new CompletableFuture |
1886 |
*/ |
1887 |
public <U,V> CompletableFuture<V> thenCombineAsync |
1888 |
(CompletableFuture<? extends U> other, |
1889 |
BiFunction<? super T,? super U,? extends V> fn) { |
1890 |
return doThenBiApply(other, fn, ForkJoinPool.commonPool()); |
1891 |
} |
1892 |
|
1893 |
/** |
1894 |
* Creates and returns a CompletableFuture that is |
1895 |
* asynchronously completed using the given executor with the |
1896 |
* result of the given function of this and the other given |
1897 |
* CompletableFuture's results when both complete. If this or |
1898 |
* the other CompletableFuture complete exceptionally, then the |
1899 |
* returned CompletableFuture also does so, with a |
1900 |
* CompletionException holding the exception as its cause. |
1901 |
* |
1902 |
* @param other the other CompletableFuture |
1903 |
* @param fn the function to use to compute the value of |
1904 |
* the returned CompletableFuture |
1905 |
* @param executor the executor to use for asynchronous execution |
1906 |
* @return the new CompletableFuture |
1907 |
*/ |
1908 |
public <U,V> CompletableFuture<V> thenCombineAsync |
1909 |
(CompletableFuture<? extends U> other, |
1910 |
BiFunction<? super T,? super U,? extends V> fn, |
1911 |
Executor executor) { |
1912 |
if (executor == null) throw new NullPointerException(); |
1913 |
return doThenBiApply(other, fn, executor); |
1914 |
} |
1915 |
|
1916 |
private <U,V> CompletableFuture<V> doThenBiApply |
1917 |
(CompletableFuture<? extends U> other, |
1918 |
BiFunction<? super T,? super U,? extends V> fn, |
1919 |
Executor e) { |
1920 |
if (other == null || fn == null) throw new NullPointerException(); |
1921 |
CompletableFuture<V> dst = new CompletableFuture<V>(); |
1922 |
BiApplyCompletion<T,U,V> d = null; |
1923 |
Object r, s = null; |
1924 |
if ((r = result) == null || (s = other.result) == null) { |
1925 |
d = new BiApplyCompletion<T,U,V>(this, other, fn, dst, e); |
1926 |
CompletionNode q = null, p = new CompletionNode(d); |
1927 |
while ((r == null && (r = result) == null) || |
1928 |
(s == null && (s = other.result) == null)) { |
1929 |
if (q != null) { |
1930 |
if (s != null || |
1931 |
UNSAFE.compareAndSwapObject |
1932 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1933 |
break; |
1934 |
} |
1935 |
else if (r != null || |
1936 |
UNSAFE.compareAndSwapObject |
1937 |
(this, COMPLETIONS, p.next = completions, p)) { |
1938 |
if (s != null) |
1939 |
break; |
1940 |
q = new CompletionNode(d); |
1941 |
} |
1942 |
} |
1943 |
} |
1944 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
1945 |
T t; U u; Throwable ex; |
1946 |
if (r instanceof AltResult) { |
1947 |
ex = ((AltResult)r).ex; |
1948 |
t = null; |
1949 |
} |
1950 |
else { |
1951 |
ex = null; |
1952 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1953 |
t = tr; |
1954 |
} |
1955 |
if (ex != null) |
1956 |
u = null; |
1957 |
else if (s instanceof AltResult) { |
1958 |
ex = ((AltResult)s).ex; |
1959 |
u = null; |
1960 |
} |
1961 |
else { |
1962 |
@SuppressWarnings("unchecked") U us = (U) s; |
1963 |
u = us; |
1964 |
} |
1965 |
V v = null; |
1966 |
if (ex == null) { |
1967 |
try { |
1968 |
if (e != null) |
1969 |
e.execute(new AsyncBiApply<T,U,V>(t, u, fn, dst)); |
1970 |
else |
1971 |
v = fn.apply(t, u); |
1972 |
} catch (Throwable rex) { |
1973 |
ex = rex; |
1974 |
} |
1975 |
} |
1976 |
if (e == null || ex != null) |
1977 |
dst.internalComplete(v, ex); |
1978 |
} |
1979 |
helpPostComplete(); |
1980 |
other.helpPostComplete(); |
1981 |
return dst; |
1982 |
} |
1983 |
|
1984 |
/** |
1985 |
* Creates and returns a CompletableFuture that is completed with |
1986 |
* the results of this and the other given CompletableFuture if |
1987 |
* both complete. If this and/or the other CompletableFuture |
1988 |
* complete exceptionally, then the returned CompletableFuture |
1989 |
* also does so, with a CompletionException holding one of these |
1990 |
* exceptions as its cause. |
1991 |
* |
1992 |
* @param other the other CompletableFuture |
1993 |
* @param block the action to perform before completing the |
1994 |
* returned CompletableFuture |
1995 |
* @return the new CompletableFuture |
1996 |
*/ |
1997 |
public <U> CompletableFuture<Void> thenAcceptBoth |
1998 |
(CompletableFuture<? extends U> other, |
1999 |
BiConsumer<? super T, ? super U> block) { |
2000 |
return doThenBiAccept(other, block, null); |
2001 |
} |
2002 |
|
2003 |
/** |
2004 |
* Creates and returns a CompletableFuture that is completed |
2005 |
* asynchronously using the {@link ForkJoinPool#commonPool()} with |
2006 |
* the results of this and the other given CompletableFuture when |
2007 |
* both complete. If this and/or the other CompletableFuture |
2008 |
* complete exceptionally, then the returned CompletableFuture |
2009 |
* also does so, with a CompletionException holding one of these |
2010 |
* exceptions as its cause. |
2011 |
* |
2012 |
* @param other the other CompletableFuture |
2013 |
* @param block the action to perform before completing the |
2014 |
* returned CompletableFuture |
2015 |
* @return the new CompletableFuture |
2016 |
*/ |
2017 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2018 |
(CompletableFuture<? extends U> other, |
2019 |
BiConsumer<? super T, ? super U> block) { |
2020 |
return doThenBiAccept(other, block, ForkJoinPool.commonPool()); |
2021 |
} |
2022 |
|
2023 |
/** |
2024 |
* Creates and returns a CompletableFuture that is completed |
2025 |
* asynchronously using the given executor with the results of |
2026 |
* this and the other given CompletableFuture when both complete. |
2027 |
* If this and/or the other CompletableFuture complete exceptionally, |
2028 |
* then the returned CompletableFuture also does so, with a |
2029 |
* CompletionException holding one of these exceptions as its cause. |
2030 |
* |
2031 |
* @param other the other CompletableFuture |
2032 |
* @param block the action to perform before completing the |
2033 |
* returned CompletableFuture |
2034 |
* @param executor the executor to use for asynchronous execution |
2035 |
* @return the new CompletableFuture |
2036 |
*/ |
2037 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2038 |
(CompletableFuture<? extends U> other, |
2039 |
BiConsumer<? super T, ? super U> block, |
2040 |
Executor executor) { |
2041 |
if (executor == null) throw new NullPointerException(); |
2042 |
return doThenBiAccept(other, block, executor); |
2043 |
} |
2044 |
|
2045 |
private <U> CompletableFuture<Void> doThenBiAccept |
2046 |
(CompletableFuture<? extends U> other, |
2047 |
BiConsumer<? super T,? super U> fn, |
2048 |
Executor e) { |
2049 |
if (other == null || fn == null) throw new NullPointerException(); |
2050 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2051 |
BiAcceptCompletion<T,U> d = null; |
2052 |
Object r, s = null; |
2053 |
if ((r = result) == null || (s = other.result) == null) { |
2054 |
d = new BiAcceptCompletion<T,U>(this, other, fn, dst, e); |
2055 |
CompletionNode q = null, p = new CompletionNode(d); |
2056 |
while ((r == null && (r = result) == null) || |
2057 |
(s == null && (s = other.result) == null)) { |
2058 |
if (q != null) { |
2059 |
if (s != null || |
2060 |
UNSAFE.compareAndSwapObject |
2061 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2062 |
break; |
2063 |
} |
2064 |
else if (r != null || |
2065 |
UNSAFE.compareAndSwapObject |
2066 |
(this, COMPLETIONS, p.next = completions, p)) { |
2067 |
if (s != null) |
2068 |
break; |
2069 |
q = new CompletionNode(d); |
2070 |
} |
2071 |
} |
2072 |
} |
2073 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
2074 |
T t; U u; Throwable ex; |
2075 |
if (r instanceof AltResult) { |
2076 |
ex = ((AltResult)r).ex; |
2077 |
t = null; |
2078 |
} |
2079 |
else { |
2080 |
ex = null; |
2081 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2082 |
t = tr; |
2083 |
} |
2084 |
if (ex != null) |
2085 |
u = null; |
2086 |
else if (s instanceof AltResult) { |
2087 |
ex = ((AltResult)s).ex; |
2088 |
u = null; |
2089 |
} |
2090 |
else { |
2091 |
@SuppressWarnings("unchecked") U us = (U) s; |
2092 |
u = us; |
2093 |
} |
2094 |
if (ex == null) { |
2095 |
try { |
2096 |
if (e != null) |
2097 |
e.execute(new AsyncBiAccept<T,U>(t, u, fn, dst)); |
2098 |
else |
2099 |
fn.accept(t, u); |
2100 |
} catch (Throwable rex) { |
2101 |
ex = rex; |
2102 |
} |
2103 |
} |
2104 |
if (e == null || ex != null) |
2105 |
dst.internalComplete(null, ex); |
2106 |
} |
2107 |
helpPostComplete(); |
2108 |
other.helpPostComplete(); |
2109 |
return dst; |
2110 |
} |
2111 |
|
2112 |
/** |
2113 |
* Creates and returns a CompletableFuture that is completed when |
2114 |
* this and the other given CompletableFuture both complete. |
2115 |
* If this and/or the other CompletableFuture complete exceptionally, |
2116 |
* then the returned CompletableFuture also does so, with a |
2117 |
* CompletionException holding one of these exceptions as its cause. |
2118 |
* |
2119 |
* @param other the other CompletableFuture |
2120 |
* @param action the action to perform before completing the |
2121 |
* returned CompletableFuture |
2122 |
* @return the new CompletableFuture |
2123 |
*/ |
2124 |
public CompletableFuture<Void> runAfterBoth(CompletableFuture<?> other, |
2125 |
Runnable action) { |
2126 |
return doThenBiRun(other, action, null); |
2127 |
} |
2128 |
|
2129 |
/** |
2130 |
* Creates and returns a CompletableFuture that is completed |
2131 |
* asynchronously using the {@link ForkJoinPool#commonPool()} |
2132 |
* when this and the other given CompletableFuture both complete. |
2133 |
* If this and/or the other CompletableFuture complete exceptionally, |
2134 |
* then the returned CompletableFuture also does so, with a |
2135 |
* CompletionException holding one of these exceptions as its cause. |
2136 |
* |
2137 |
* @param other the other CompletableFuture |
2138 |
* @param action the action to perform before completing the |
2139 |
* returned CompletableFuture |
2140 |
* @return the new CompletableFuture |
2141 |
*/ |
2142 |
public CompletableFuture<Void> runAfterBothAsync(CompletableFuture<?> other, |
2143 |
Runnable action) { |
2144 |
return doThenBiRun(other, action, ForkJoinPool.commonPool()); |
2145 |
} |
2146 |
|
2147 |
/** |
2148 |
* Creates and returns a CompletableFuture that is completed |
2149 |
* asynchronously using the given executor when this and the |
2150 |
* other given CompletableFuture both complete. |
2151 |
* If this and/or the other CompletableFuture complete exceptionally, |
2152 |
* then the returned CompletableFuture also does so, with a |
2153 |
* CompletionException holding one of these exceptions as its cause. |
2154 |
* |
2155 |
* @param other the other CompletableFuture |
2156 |
* @param action the action to perform before completing the |
2157 |
* returned CompletableFuture |
2158 |
* @param executor the executor to use for asynchronous execution |
2159 |
* @return the new CompletableFuture |
2160 |
*/ |
2161 |
public CompletableFuture<Void> runAfterBothAsync(CompletableFuture<?> other, |
2162 |
Runnable action, |
2163 |
Executor executor) { |
2164 |
if (executor == null) throw new NullPointerException(); |
2165 |
return doThenBiRun(other, action, executor); |
2166 |
} |
2167 |
|
2168 |
private CompletableFuture<Void> doThenBiRun(CompletableFuture<?> other, |
2169 |
Runnable action, |
2170 |
Executor e) { |
2171 |
if (other == null || action == null) throw new NullPointerException(); |
2172 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2173 |
BiRunCompletion<T> d = null; |
2174 |
Object r, s = null; |
2175 |
if ((r = result) == null || (s = other.result) == null) { |
2176 |
d = new BiRunCompletion<T>(this, other, action, dst, e); |
2177 |
CompletionNode q = null, p = new CompletionNode(d); |
2178 |
while ((r == null && (r = result) == null) || |
2179 |
(s == null && (s = other.result) == null)) { |
2180 |
if (q != null) { |
2181 |
if (s != null || |
2182 |
UNSAFE.compareAndSwapObject |
2183 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2184 |
break; |
2185 |
} |
2186 |
else if (r != null || |
2187 |
UNSAFE.compareAndSwapObject |
2188 |
(this, COMPLETIONS, p.next = completions, p)) { |
2189 |
if (s != null) |
2190 |
break; |
2191 |
q = new CompletionNode(d); |
2192 |
} |
2193 |
} |
2194 |
} |
2195 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
2196 |
Throwable ex; |
2197 |
if (r instanceof AltResult) |
2198 |
ex = ((AltResult)r).ex; |
2199 |
else |
2200 |
ex = null; |
2201 |
if (ex == null && (s instanceof AltResult)) |
2202 |
ex = ((AltResult)s).ex; |
2203 |
if (ex == null) { |
2204 |
try { |
2205 |
if (e != null) |
2206 |
e.execute(new AsyncRun(action, dst)); |
2207 |
else |
2208 |
action.run(); |
2209 |
} catch (Throwable rex) { |
2210 |
ex = rex; |
2211 |
} |
2212 |
} |
2213 |
if (e == null || ex != null) |
2214 |
dst.internalComplete(null, ex); |
2215 |
} |
2216 |
helpPostComplete(); |
2217 |
other.helpPostComplete(); |
2218 |
return dst; |
2219 |
} |
2220 |
|
2221 |
/** |
2222 |
* Creates and returns a CompletableFuture that is completed with |
2223 |
* the result of the given function of either this or the other |
2224 |
* given CompletableFuture's results when either complete. |
2225 |
* If this and/or the other CompletableFuture complete exceptionally, |
2226 |
* then the returned CompletableFuture may also do so, with a |
2227 |
* CompletionException holding one of these exceptions as its cause. |
2228 |
* No guarantees are made about which result or exception is used |
2229 |
* in the returned CompletableFuture. |
2230 |
* |
2231 |
* @param other the other CompletableFuture |
2232 |
* @param fn the function to use to compute the value of |
2233 |
* the returned CompletableFuture |
2234 |
* @return the new CompletableFuture |
2235 |
*/ |
2236 |
public <U> CompletableFuture<U> applyToEither |
2237 |
(CompletableFuture<? extends T> other, |
2238 |
Function<? super T, U> fn) { |
2239 |
return doOrApply(other, fn, null); |
2240 |
} |
2241 |
|
2242 |
/** |
2243 |
* Creates and returns a CompletableFuture that is completed |
2244 |
* asynchronously using the {@link ForkJoinPool#commonPool()} with |
2245 |
* the result of the given function of either this or the other |
2246 |
* given CompletableFuture's results when either complete. |
2247 |
* If this and/or the other CompletableFuture complete exceptionally, |
2248 |
* then the returned CompletableFuture may also do so, with a |
2249 |
* CompletionException holding one of these exceptions as its cause. |
2250 |
* No guarantees are made about which result or exception is used |
2251 |
* in the returned CompletableFuture. |
2252 |
* |
2253 |
* @param other the other CompletableFuture |
2254 |
* @param fn the function to use to compute the value of |
2255 |
* the returned CompletableFuture |
2256 |
* @return the new CompletableFuture |
2257 |
*/ |
2258 |
public <U> CompletableFuture<U> applyToEitherAsync |
2259 |
(CompletableFuture<? extends T> other, |
2260 |
Function<? super T, U> fn) { |
2261 |
return doOrApply(other, fn, ForkJoinPool.commonPool()); |
2262 |
} |
2263 |
|
2264 |
/** |
2265 |
* Creates and returns a CompletableFuture that is completed |
2266 |
* asynchronously using the given executor with the result of the |
2267 |
* given function of either this or the other given |
2268 |
* CompletableFuture's results when either complete. If this |
2269 |
* and/or the other CompletableFuture complete exceptionally, then |
2270 |
* the returned CompletableFuture may also do so, with a |
2271 |
* CompletionException holding one of these exceptions as its cause. |
2272 |
* No guarantees are made about which result or exception is used |
2273 |
* in the returned CompletableFuture. |
2274 |
* |
2275 |
* @param other the other CompletableFuture |
2276 |
* @param fn the function to use to compute the value of |
2277 |
* the returned CompletableFuture |
2278 |
* @param executor the executor to use for asynchronous execution |
2279 |
* @return the new CompletableFuture |
2280 |
*/ |
2281 |
public <U> CompletableFuture<U> applyToEitherAsync |
2282 |
(CompletableFuture<? extends T> other, |
2283 |
Function<? super T, U> fn, |
2284 |
Executor executor) { |
2285 |
if (executor == null) throw new NullPointerException(); |
2286 |
return doOrApply(other, fn, executor); |
2287 |
} |
2288 |
|
2289 |
private <U> CompletableFuture<U> doOrApply |
2290 |
(CompletableFuture<? extends T> other, |
2291 |
Function<? super T, U> fn, |
2292 |
Executor e) { |
2293 |
if (other == null || fn == null) throw new NullPointerException(); |
2294 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
2295 |
OrApplyCompletion<T,U> d = null; |
2296 |
Object r; |
2297 |
if ((r = result) == null && (r = other.result) == null) { |
2298 |
d = new OrApplyCompletion<T,U>(this, other, fn, dst, e); |
2299 |
CompletionNode q = null, p = new CompletionNode(d); |
2300 |
while ((r = result) == null && (r = other.result) == null) { |
2301 |
if (q != null) { |
2302 |
if (UNSAFE.compareAndSwapObject |
2303 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2304 |
break; |
2305 |
} |
2306 |
else if (UNSAFE.compareAndSwapObject |
2307 |
(this, COMPLETIONS, p.next = completions, p)) |
2308 |
q = new CompletionNode(d); |
2309 |
} |
2310 |
} |
2311 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2312 |
T t; Throwable ex; |
2313 |
if (r instanceof AltResult) { |
2314 |
ex = ((AltResult)r).ex; |
2315 |
t = null; |
2316 |
} |
2317 |
else { |
2318 |
ex = null; |
2319 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2320 |
t = tr; |
2321 |
} |
2322 |
U u = null; |
2323 |
if (ex == null) { |
2324 |
try { |
2325 |
if (e != null) |
2326 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
2327 |
else |
2328 |
u = fn.apply(t); |
2329 |
} catch (Throwable rex) { |
2330 |
ex = rex; |
2331 |
} |
2332 |
} |
2333 |
if (e == null || ex != null) |
2334 |
dst.internalComplete(u, ex); |
2335 |
} |
2336 |
helpPostComplete(); |
2337 |
other.helpPostComplete(); |
2338 |
return dst; |
2339 |
} |
2340 |
|
2341 |
/** |
2342 |
* Creates and returns a CompletableFuture that is completed after |
2343 |
* performing the given action with the result of either this or the |
2344 |
* other given CompletableFuture's result, when either complete. |
2345 |
* If this and/or the other CompletableFuture complete exceptionally, |
2346 |
* then the returned CompletableFuture may also do so, with a |
2347 |
* CompletionException holding one of these exceptions as its cause. |
2348 |
* No guarantees are made about which exception is used in the |
2349 |
* returned CompletableFuture. |
2350 |
* |
2351 |
* @param other the other CompletableFuture |
2352 |
* @param block the action to perform before completing the |
2353 |
* returned CompletableFuture |
2354 |
* @return the new CompletableFuture |
2355 |
*/ |
2356 |
public CompletableFuture<Void> acceptEither |
2357 |
(CompletableFuture<? extends T> other, |
2358 |
Consumer<? super T> block) { |
2359 |
return doOrAccept(other, block, null); |
2360 |
} |
2361 |
|
2362 |
/** |
2363 |
* Creates and returns a CompletableFuture that is completed |
2364 |
* asynchronously using the {@link ForkJoinPool#commonPool()}, |
2365 |
* performing the given action with the result of either this or |
2366 |
* the other given CompletableFuture's result, when either complete. |
2367 |
* If this and/or the other CompletableFuture complete exceptionally, |
2368 |
* then the returned CompletableFuture may also do so, with a |
2369 |
* CompletionException holding one of these exceptions as its cause. |
2370 |
* No guarantees are made about which exception is used in the |
2371 |
* returned CompletableFuture. |
2372 |
* |
2373 |
* @param other the other CompletableFuture |
2374 |
* @param block the action to perform before completing the |
2375 |
* returned CompletableFuture |
2376 |
* @return the new CompletableFuture |
2377 |
*/ |
2378 |
public CompletableFuture<Void> acceptEitherAsync |
2379 |
(CompletableFuture<? extends T> other, |
2380 |
Consumer<? super T> block) { |
2381 |
return doOrAccept(other, block, ForkJoinPool.commonPool()); |
2382 |
} |
2383 |
|
2384 |
/** |
2385 |
* Creates and returns a CompletableFuture that is completed |
2386 |
* asynchronously using the given executor, performing the given |
2387 |
* action with the result of either this or the other given |
2388 |
* CompletableFuture's result, when either complete. |
2389 |
* If this and/or the other CompletableFuture complete exceptionally, |
2390 |
* then the returned CompletableFuture may also do so, with a |
2391 |
* CompletionException holding one of these exceptions as its cause. |
2392 |
* No guarantees are made about which exception is used in the |
2393 |
* returned CompletableFuture. |
2394 |
* |
2395 |
* @param other the other CompletableFuture |
2396 |
* @param block the action to perform before completing the |
2397 |
* returned CompletableFuture |
2398 |
* @param executor the executor to use for asynchronous execution |
2399 |
* @return the new CompletableFuture |
2400 |
*/ |
2401 |
public CompletableFuture<Void> acceptEitherAsync |
2402 |
(CompletableFuture<? extends T> other, |
2403 |
Consumer<? super T> block, |
2404 |
Executor executor) { |
2405 |
if (executor == null) throw new NullPointerException(); |
2406 |
return doOrAccept(other, block, executor); |
2407 |
} |
2408 |
|
2409 |
private CompletableFuture<Void> doOrAccept |
2410 |
(CompletableFuture<? extends T> other, |
2411 |
Consumer<? super T> fn, |
2412 |
Executor e) { |
2413 |
if (other == null || fn == null) throw new NullPointerException(); |
2414 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2415 |
OrAcceptCompletion<T> d = null; |
2416 |
Object r; |
2417 |
if ((r = result) == null && (r = other.result) == null) { |
2418 |
d = new OrAcceptCompletion<T>(this, other, fn, dst, e); |
2419 |
CompletionNode q = null, p = new CompletionNode(d); |
2420 |
while ((r = result) == null && (r = other.result) == null) { |
2421 |
if (q != null) { |
2422 |
if (UNSAFE.compareAndSwapObject |
2423 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2424 |
break; |
2425 |
} |
2426 |
else if (UNSAFE.compareAndSwapObject |
2427 |
(this, COMPLETIONS, p.next = completions, p)) |
2428 |
q = new CompletionNode(d); |
2429 |
} |
2430 |
} |
2431 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2432 |
T t; Throwable ex; |
2433 |
if (r instanceof AltResult) { |
2434 |
ex = ((AltResult)r).ex; |
2435 |
t = null; |
2436 |
} |
2437 |
else { |
2438 |
ex = null; |
2439 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2440 |
t = tr; |
2441 |
} |
2442 |
if (ex == null) { |
2443 |
try { |
2444 |
if (e != null) |
2445 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
2446 |
else |
2447 |
fn.accept(t); |
2448 |
} catch (Throwable rex) { |
2449 |
ex = rex; |
2450 |
} |
2451 |
} |
2452 |
if (e == null || ex != null) |
2453 |
dst.internalComplete(null, ex); |
2454 |
} |
2455 |
helpPostComplete(); |
2456 |
other.helpPostComplete(); |
2457 |
return dst; |
2458 |
} |
2459 |
|
2460 |
/** |
2461 |
* Creates and returns a CompletableFuture that is completed |
2462 |
* after this or the other given CompletableFuture complete. |
2463 |
* If this and/or the other CompletableFuture complete exceptionally, |
2464 |
* then the returned CompletableFuture may also do so, with a |
2465 |
* CompletionException holding one of these exceptions as its cause. |
2466 |
* No guarantees are made about which exception is used in the |
2467 |
* returned CompletableFuture. |
2468 |
* |
2469 |
* @param other the other CompletableFuture |
2470 |
* @param action the action to perform before completing the |
2471 |
* returned CompletableFuture |
2472 |
* @return the new CompletableFuture |
2473 |
*/ |
2474 |
public CompletableFuture<Void> runAfterEither(CompletableFuture<?> other, |
2475 |
Runnable action) { |
2476 |
return doOrRun(other, action, null); |
2477 |
} |
2478 |
|
2479 |
/** |
2480 |
* Creates and returns a CompletableFuture that is completed |
2481 |
* asynchronously using the {@link ForkJoinPool#commonPool()} |
2482 |
* after this or the other given CompletableFuture complete. |
2483 |
* If this and/or the other CompletableFuture complete exceptionally, |
2484 |
* then the returned CompletableFuture may also do so, with a |
2485 |
* CompletionException holding one of these exceptions as its cause. |
2486 |
* No guarantees are made about which exception is used in the |
2487 |
* returned CompletableFuture. |
2488 |
* |
2489 |
* @param other the other CompletableFuture |
2490 |
* @param action the action to perform before completing the |
2491 |
* returned CompletableFuture |
2492 |
* @return the new CompletableFuture |
2493 |
*/ |
2494 |
public CompletableFuture<Void> runAfterEitherAsync |
2495 |
(CompletableFuture<?> other, |
2496 |
Runnable action) { |
2497 |
return doOrRun(other, action, ForkJoinPool.commonPool()); |
2498 |
} |
2499 |
|
2500 |
/** |
2501 |
* Creates and returns a CompletableFuture that is completed |
2502 |
* asynchronously using the given executor after this or the other |
2503 |
* given CompletableFuture complete. |
2504 |
* If this and/or the other CompletableFuture complete exceptionally, |
2505 |
* then the returned CompletableFuture may also do so, with a |
2506 |
* CompletionException holding one of these exceptions as its cause. |
2507 |
* No guarantees are made about which exception is used in the |
2508 |
* returned CompletableFuture. |
2509 |
* |
2510 |
* @param other the other CompletableFuture |
2511 |
* @param action the action to perform before completing the |
2512 |
* returned CompletableFuture |
2513 |
* @param executor the executor to use for asynchronous execution |
2514 |
* @return the new CompletableFuture |
2515 |
*/ |
2516 |
public CompletableFuture<Void> runAfterEitherAsync |
2517 |
(CompletableFuture<?> other, |
2518 |
Runnable action, |
2519 |
Executor executor) { |
2520 |
if (executor == null) throw new NullPointerException(); |
2521 |
return doOrRun(other, action, executor); |
2522 |
} |
2523 |
|
2524 |
private CompletableFuture<Void> doOrRun(CompletableFuture<?> other, |
2525 |
Runnable action, |
2526 |
Executor e) { |
2527 |
if (other == null || action == null) throw new NullPointerException(); |
2528 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2529 |
OrRunCompletion<T> d = null; |
2530 |
Object r; |
2531 |
if ((r = result) == null && (r = other.result) == null) { |
2532 |
d = new OrRunCompletion<T>(this, other, action, dst, e); |
2533 |
CompletionNode q = null, p = new CompletionNode(d); |
2534 |
while ((r = result) == null && (r = other.result) == null) { |
2535 |
if (q != null) { |
2536 |
if (UNSAFE.compareAndSwapObject |
2537 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2538 |
break; |
2539 |
} |
2540 |
else if (UNSAFE.compareAndSwapObject |
2541 |
(this, COMPLETIONS, p.next = completions, p)) |
2542 |
q = new CompletionNode(d); |
2543 |
} |
2544 |
} |
2545 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2546 |
Throwable ex; |
2547 |
if (r instanceof AltResult) |
2548 |
ex = ((AltResult)r).ex; |
2549 |
else |
2550 |
ex = null; |
2551 |
if (ex == null) { |
2552 |
try { |
2553 |
if (e != null) |
2554 |
e.execute(new AsyncRun(action, dst)); |
2555 |
else |
2556 |
action.run(); |
2557 |
} catch (Throwable rex) { |
2558 |
ex = rex; |
2559 |
} |
2560 |
} |
2561 |
if (e == null || ex != null) |
2562 |
dst.internalComplete(null, ex); |
2563 |
} |
2564 |
helpPostComplete(); |
2565 |
other.helpPostComplete(); |
2566 |
return dst; |
2567 |
} |
2568 |
|
2569 |
/** |
2570 |
* Returns a CompletableFuture (or an equivalent one) produced by |
2571 |
* the given function of the result of this CompletableFuture when |
2572 |
* completed. If this CompletableFuture completes exceptionally, |
2573 |
* then the returned CompletableFuture also does so, with a |
2574 |
* CompletionException holding this exception as its cause. |
2575 |
* |
2576 |
* @param fn the function returning a new CompletableFuture |
2577 |
* @return the CompletableFuture, that {@code isDone()} upon |
2578 |
* return if completed by the given function, or an exception |
2579 |
* occurs |
2580 |
*/ |
2581 |
public <U> CompletableFuture<U> thenCompose |
2582 |
(Function<? super T, CompletableFuture<U>> fn) { |
2583 |
return doCompose(fn, null); |
2584 |
} |
2585 |
|
2586 |
/** |
2587 |
* Returns a CompletableFuture (or an equivalent one) produced |
2588 |
* asynchronously using the {@link ForkJoinPool#commonPool()} by |
2589 |
* the given function of the result of this CompletableFuture when |
2590 |
* completed. If this CompletableFuture completes exceptionally, |
2591 |
* then the returned CompletableFuture also does so, with a |
2592 |
* CompletionException holding this exception as its cause. |
2593 |
* |
2594 |
* @param fn the function returning a new CompletableFuture |
2595 |
* @return the CompletableFuture, that {@code isDone()} upon |
2596 |
* return if completed by the given function, or an exception |
2597 |
* occurs |
2598 |
*/ |
2599 |
public <U> CompletableFuture<U> thenComposeAsync |
2600 |
(Function<? super T, CompletableFuture<U>> fn) { |
2601 |
return doCompose(fn, ForkJoinPool.commonPool()); |
2602 |
} |
2603 |
|
2604 |
/** |
2605 |
* Returns a CompletableFuture (or an equivalent one) produced |
2606 |
* asynchronously using the given executor by the given function |
2607 |
* of the result of this CompletableFuture when completed. |
2608 |
* If this CompletableFuture completes exceptionally, then the |
2609 |
* returned CompletableFuture also does so, with a |
2610 |
* CompletionException holding this exception as its cause. |
2611 |
* |
2612 |
* @param fn the function returning a new CompletableFuture |
2613 |
* @param executor the executor to use for asynchronous execution |
2614 |
* @return the CompletableFuture, that {@code isDone()} upon |
2615 |
* return if completed by the given function, or an exception |
2616 |
* occurs |
2617 |
*/ |
2618 |
public <U> CompletableFuture<U> thenComposeAsync |
2619 |
(Function<? super T, CompletableFuture<U>> fn, |
2620 |
Executor executor) { |
2621 |
if (executor == null) throw new NullPointerException(); |
2622 |
return doCompose(fn, executor); |
2623 |
} |
2624 |
|
2625 |
private <U> CompletableFuture<U> doCompose |
2626 |
(Function<? super T, CompletableFuture<U>> fn, |
2627 |
Executor e) { |
2628 |
if (fn == null) throw new NullPointerException(); |
2629 |
CompletableFuture<U> dst = null; |
2630 |
ComposeCompletion<T,U> d = null; |
2631 |
Object r; |
2632 |
if ((r = result) == null) { |
2633 |
dst = new CompletableFuture<U>(); |
2634 |
CompletionNode p = new CompletionNode |
2635 |
(d = new ComposeCompletion<T,U>(this, fn, dst, e)); |
2636 |
while ((r = result) == null) { |
2637 |
if (UNSAFE.compareAndSwapObject |
2638 |
(this, COMPLETIONS, p.next = completions, p)) |
2639 |
break; |
2640 |
} |
2641 |
} |
2642 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2643 |
T t; Throwable ex; |
2644 |
if (r instanceof AltResult) { |
2645 |
ex = ((AltResult)r).ex; |
2646 |
t = null; |
2647 |
} |
2648 |
else { |
2649 |
ex = null; |
2650 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2651 |
t = tr; |
2652 |
} |
2653 |
if (ex == null) { |
2654 |
if (e != null) { |
2655 |
if (dst == null) |
2656 |
dst = new CompletableFuture<U>(); |
2657 |
e.execute(new AsyncCompose<T,U>(t, fn, dst)); |
2658 |
} |
2659 |
else { |
2660 |
try { |
2661 |
dst = fn.apply(t); |
2662 |
} catch (Throwable rex) { |
2663 |
ex = rex; |
2664 |
} |
2665 |
if (dst == null) { |
2666 |
dst = new CompletableFuture<U>(); |
2667 |
if (ex == null) |
2668 |
ex = new NullPointerException(); |
2669 |
} |
2670 |
} |
2671 |
} |
2672 |
if (e == null && ex != null) |
2673 |
dst.internalComplete(null, ex); |
2674 |
} |
2675 |
helpPostComplete(); |
2676 |
dst.helpPostComplete(); |
2677 |
return dst; |
2678 |
} |
2679 |
|
2680 |
/** |
2681 |
* Creates and returns a CompletableFuture that is completed with |
2682 |
* the result of the given function of the exception triggering |
2683 |
* this CompletableFuture's completion when it completes |
2684 |
* exceptionally; Otherwise, if this CompletableFuture completes |
2685 |
* normally, then the returned CompletableFuture also completes |
2686 |
* normally with the same value. |
2687 |
* |
2688 |
* @param fn the function to use to compute the value of the |
2689 |
* returned CompletableFuture if this CompletableFuture completed |
2690 |
* exceptionally |
2691 |
* @return the new CompletableFuture |
2692 |
*/ |
2693 |
public CompletableFuture<T> exceptionally |
2694 |
(Function<Throwable, ? extends T> fn) { |
2695 |
if (fn == null) throw new NullPointerException(); |
2696 |
CompletableFuture<T> dst = new CompletableFuture<T>(); |
2697 |
ExceptionCompletion<T> d = null; |
2698 |
Object r; |
2699 |
if ((r = result) == null) { |
2700 |
CompletionNode p = |
2701 |
new CompletionNode(d = new ExceptionCompletion<T>(this, fn, dst)); |
2702 |
while ((r = result) == null) { |
2703 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2704 |
p.next = completions, p)) |
2705 |
break; |
2706 |
} |
2707 |
} |
2708 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2709 |
T t = null; Throwable ex, dx = null; |
2710 |
if (r instanceof AltResult) { |
2711 |
if ((ex = ((AltResult)r).ex) != null) { |
2712 |
try { |
2713 |
t = fn.apply(ex); |
2714 |
} catch (Throwable rex) { |
2715 |
dx = rex; |
2716 |
} |
2717 |
} |
2718 |
} |
2719 |
else { |
2720 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2721 |
t = tr; |
2722 |
} |
2723 |
dst.internalComplete(t, dx); |
2724 |
} |
2725 |
helpPostComplete(); |
2726 |
return dst; |
2727 |
} |
2728 |
|
2729 |
/** |
2730 |
* Creates and returns a CompletableFuture that is completed with |
2731 |
* the result of the given function of the result and exception of |
2732 |
* this CompletableFuture's completion when it completes. The |
2733 |
* given function is invoked with the result (or {@code null} if |
2734 |
* none) and the exception (or {@code null} if none) of this |
2735 |
* CompletableFuture when complete. |
2736 |
* |
2737 |
* @param fn the function to use to compute the value of the |
2738 |
* returned CompletableFuture |
2739 |
* @return the new CompletableFuture |
2740 |
*/ |
2741 |
public <U> CompletableFuture<U> handle |
2742 |
(BiFunction<? super T, Throwable, ? extends U> fn) { |
2743 |
if (fn == null) throw new NullPointerException(); |
2744 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
2745 |
HandleCompletion<T,U> d = null; |
2746 |
Object r; |
2747 |
if ((r = result) == null) { |
2748 |
CompletionNode p = |
2749 |
new CompletionNode(d = new HandleCompletion<T,U>(this, fn, dst)); |
2750 |
while ((r = result) == null) { |
2751 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2752 |
p.next = completions, p)) |
2753 |
break; |
2754 |
} |
2755 |
} |
2756 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2757 |
T t; Throwable ex; |
2758 |
if (r instanceof AltResult) { |
2759 |
ex = ((AltResult)r).ex; |
2760 |
t = null; |
2761 |
} |
2762 |
else { |
2763 |
ex = null; |
2764 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2765 |
t = tr; |
2766 |
} |
2767 |
U u; Throwable dx; |
2768 |
try { |
2769 |
u = fn.apply(t, ex); |
2770 |
dx = null; |
2771 |
} catch (Throwable rex) { |
2772 |
dx = rex; |
2773 |
u = null; |
2774 |
} |
2775 |
dst.internalComplete(u, dx); |
2776 |
} |
2777 |
helpPostComplete(); |
2778 |
return dst; |
2779 |
} |
2780 |
|
2781 |
|
2782 |
/* ------------- Arbitrary-arity constructions -------------- */ |
2783 |
|
2784 |
/* |
2785 |
* The basic plan of attack is to recursively form binary |
2786 |
* completion trees of elements. This can be overkill for small |
2787 |
* sets, but scales nicely. The And/All vs Or/Any forms use the |
2788 |
* same idea, but details differ. |
2789 |
*/ |
2790 |
|
2791 |
/** |
2792 |
* Returns a new CompletableFuture that is completed when all of |
2793 |
* the given CompletableFutures complete. If any of the component |
2794 |
* CompletableFutures complete exceptionally, then so does the |
2795 |
* returned CompletableFuture. Otherwise, the results, if any, of |
2796 |
* the component CompletableFutures are not reflected in the |
2797 |
* returned CompletableFuture, but may be obtained by inspecting |
2798 |
* them individually. If the number of components is zero, returns |
2799 |
* a CompletableFuture completed with the value {@code null}. |
2800 |
* |
2801 |
* <p>Among the applications of this method is to await completion |
2802 |
* of a set of independent CompletableFutures before continuing a |
2803 |
* program, as in: {@code CompletableFuture.allOf(c1, c2, |
2804 |
* c3).join();}. |
2805 |
* |
2806 |
* @param cfs the CompletableFutures |
2807 |
* @return a CompletableFuture that is complete when all of the |
2808 |
* given CompletableFutures complete |
2809 |
* @throws NullPointerException if the array or any of its elements are |
2810 |
* {@code null} |
2811 |
*/ |
2812 |
public static CompletableFuture<Void> allOf(CompletableFuture<?>... cfs) { |
2813 |
int len = cfs.length; // Directly handle empty and singleton cases |
2814 |
if (len > 1) |
2815 |
return allTree(cfs, 0, len - 1); |
2816 |
else { |
2817 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2818 |
CompletableFuture<?> f; |
2819 |
if (len == 0) |
2820 |
dst.result = NIL; |
2821 |
else if ((f = cfs[0]) == null) |
2822 |
throw new NullPointerException(); |
2823 |
else { |
2824 |
ThenCopy d = null; |
2825 |
CompletionNode p = null; |
2826 |
Object r; |
2827 |
while ((r = f.result) == null) { |
2828 |
if (d == null) |
2829 |
d = new ThenCopy(f, dst); |
2830 |
else if (p == null) |
2831 |
p = new CompletionNode(d); |
2832 |
else if (UNSAFE.compareAndSwapObject |
2833 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2834 |
break; |
2835 |
} |
2836 |
if (r != null && (d == null || d.compareAndSet(0, 1))) |
2837 |
dst.internalComplete(null, (r instanceof AltResult) ? |
2838 |
((AltResult)r).ex : null); |
2839 |
f.helpPostComplete(); |
2840 |
} |
2841 |
return dst; |
2842 |
} |
2843 |
} |
2844 |
|
2845 |
/** |
2846 |
* Recursively constructs an And'ed tree of CompletableFutures. |
2847 |
* Called only when array known to have at least two elements. |
2848 |
*/ |
2849 |
private static CompletableFuture<Void> allTree(CompletableFuture<?>[] cfs, |
2850 |
int lo, int hi) { |
2851 |
CompletableFuture<?> fst, snd; |
2852 |
int mid = (lo + hi) >>> 1; |
2853 |
if ((fst = (lo == mid ? cfs[lo] : allTree(cfs, lo, mid))) == null || |
2854 |
(snd = (hi == mid+1 ? cfs[hi] : allTree(cfs, mid+1, hi))) == null) |
2855 |
throw new NullPointerException(); |
2856 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2857 |
AndCompletion d = null; |
2858 |
CompletionNode p = null, q = null; |
2859 |
Object r = null, s = null; |
2860 |
while ((r = fst.result) == null || (s = snd.result) == null) { |
2861 |
if (d == null) |
2862 |
d = new AndCompletion(fst, snd, dst); |
2863 |
else if (p == null) |
2864 |
p = new CompletionNode(d); |
2865 |
else if (q == null) { |
2866 |
if (UNSAFE.compareAndSwapObject |
2867 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
2868 |
q = new CompletionNode(d); |
2869 |
} |
2870 |
else if (UNSAFE.compareAndSwapObject |
2871 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
2872 |
break; |
2873 |
} |
2874 |
if ((r != null || (r = fst.result) != null) && |
2875 |
(s != null || (s = snd.result) != null) && |
2876 |
(d == null || d.compareAndSet(0, 1))) { |
2877 |
Throwable ex; |
2878 |
if (r instanceof AltResult) |
2879 |
ex = ((AltResult)r).ex; |
2880 |
else |
2881 |
ex = null; |
2882 |
if (ex == null && (s instanceof AltResult)) |
2883 |
ex = ((AltResult)s).ex; |
2884 |
dst.internalComplete(null, ex); |
2885 |
} |
2886 |
fst.helpPostComplete(); |
2887 |
snd.helpPostComplete(); |
2888 |
return dst; |
2889 |
} |
2890 |
|
2891 |
/** |
2892 |
* Returns a new CompletableFuture that is completed when any of |
2893 |
* the component CompletableFutures complete; with the same result if |
2894 |
* it completed normally, otherwise exceptionally. If the number |
2895 |
* of components is zero, returns an incomplete CompletableFuture. |
2896 |
* |
2897 |
* @param cfs the CompletableFutures |
2898 |
* @return a CompletableFuture that is complete when any of the |
2899 |
* given CompletableFutures complete |
2900 |
* @throws NullPointerException if the array or any of its elements are |
2901 |
* {@code null} |
2902 |
*/ |
2903 |
public static CompletableFuture<?> anyOf(CompletableFuture<?>... cfs) { |
2904 |
int len = cfs.length; // Same idea as allOf |
2905 |
if (len > 1) |
2906 |
return anyTree(cfs, 0, len - 1); |
2907 |
else { |
2908 |
CompletableFuture<?> dst = new CompletableFuture<Object>(); |
2909 |
CompletableFuture<?> f; |
2910 |
if (len == 0) |
2911 |
; // skip |
2912 |
else if ((f = cfs[0]) == null) |
2913 |
throw new NullPointerException(); |
2914 |
else { |
2915 |
ThenCopy d = null; |
2916 |
CompletionNode p = null; |
2917 |
Object r; |
2918 |
while ((r = f.result) == null) { |
2919 |
if (d == null) |
2920 |
d = new ThenCopy(f, dst); |
2921 |
else if (p == null) |
2922 |
p = new CompletionNode(d); |
2923 |
else if (UNSAFE.compareAndSwapObject |
2924 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2925 |
break; |
2926 |
} |
2927 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2928 |
Throwable ex; Object t; |
2929 |
if (r instanceof AltResult) { |
2930 |
ex = ((AltResult)r).ex; |
2931 |
t = null; |
2932 |
} |
2933 |
else { |
2934 |
ex = null; |
2935 |
t = r; |
2936 |
} |
2937 |
dst.internalComplete(t, ex); |
2938 |
} |
2939 |
f.helpPostComplete(); |
2940 |
} |
2941 |
return dst; |
2942 |
} |
2943 |
} |
2944 |
|
2945 |
/** |
2946 |
* Recursively constructs an Or'ed tree of CompletableFutures. |
2947 |
*/ |
2948 |
private static CompletableFuture<?> anyTree(CompletableFuture<?>[] cfs, |
2949 |
int lo, int hi) { |
2950 |
CompletableFuture<?> fst, snd; |
2951 |
int mid = (lo + hi) >>> 1; |
2952 |
if ((fst = (lo == mid ? cfs[lo] : anyTree(cfs, lo, mid))) == null || |
2953 |
(snd = (hi == mid+1 ? cfs[hi] : anyTree(cfs, mid+1, hi))) == null) |
2954 |
throw new NullPointerException(); |
2955 |
CompletableFuture<?> dst = new CompletableFuture<Object>(); |
2956 |
OrCompletion d = null; |
2957 |
CompletionNode p = null, q = null; |
2958 |
Object r; |
2959 |
while ((r = fst.result) == null && (r = snd.result) == null) { |
2960 |
if (d == null) |
2961 |
d = new OrCompletion(fst, snd, dst); |
2962 |
else if (p == null) |
2963 |
p = new CompletionNode(d); |
2964 |
else if (q == null) { |
2965 |
if (UNSAFE.compareAndSwapObject |
2966 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
2967 |
q = new CompletionNode(d); |
2968 |
} |
2969 |
else if (UNSAFE.compareAndSwapObject |
2970 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
2971 |
break; |
2972 |
} |
2973 |
if ((r != null || (r = fst.result) != null || |
2974 |
(r = snd.result) != null) && |
2975 |
(d == null || d.compareAndSet(0, 1))) { |
2976 |
Throwable ex; Object t; |
2977 |
if (r instanceof AltResult) { |
2978 |
ex = ((AltResult)r).ex; |
2979 |
t = null; |
2980 |
} |
2981 |
else { |
2982 |
ex = null; |
2983 |
t = r; |
2984 |
} |
2985 |
dst.internalComplete(t, ex); |
2986 |
} |
2987 |
fst.helpPostComplete(); |
2988 |
snd.helpPostComplete(); |
2989 |
return dst; |
2990 |
} |
2991 |
|
2992 |
|
2993 |
/* ------------- Control and status methods -------------- */ |
2994 |
|
2995 |
/** |
2996 |
* If not already completed, completes this CompletableFuture with |
2997 |
* a {@link CancellationException}. Dependent CompletableFutures |
2998 |
* that have not already completed will also complete |
2999 |
* exceptionally, with a {@link CompletionException} caused by |
3000 |
* this {@code CancellationException}. |
3001 |
* |
3002 |
* @param mayInterruptIfRunning this value has no effect in this |
3003 |
* implementation because interrupts are not used to control |
3004 |
* processing. |
3005 |
* |
3006 |
* @return {@code true} if this task is now cancelled |
3007 |
*/ |
3008 |
public boolean cancel(boolean mayInterruptIfRunning) { |
3009 |
boolean cancelled = (result == null) && |
3010 |
UNSAFE.compareAndSwapObject |
3011 |
(this, RESULT, null, new AltResult(new CancellationException())); |
3012 |
postComplete(); |
3013 |
return cancelled || isCancelled(); |
3014 |
} |
3015 |
|
3016 |
/** |
3017 |
* Returns {@code true} if this CompletableFuture was cancelled |
3018 |
* before it completed normally. |
3019 |
* |
3020 |
* @return {@code true} if this CompletableFuture was cancelled |
3021 |
* before it completed normally |
3022 |
*/ |
3023 |
public boolean isCancelled() { |
3024 |
Object r; |
3025 |
return ((r = result) instanceof AltResult) && |
3026 |
(((AltResult)r).ex instanceof CancellationException); |
3027 |
} |
3028 |
|
3029 |
/** |
3030 |
* Forcibly sets or resets the value subsequently returned by |
3031 |
* method {@link #get()} and related methods, whether or not |
3032 |
* already completed. This method is designed for use only in |
3033 |
* error recovery actions, and even in such situations may result |
3034 |
* in ongoing dependent completions using established versus |
3035 |
* overwritten outcomes. |
3036 |
* |
3037 |
* @param value the completion value |
3038 |
*/ |
3039 |
public void obtrudeValue(T value) { |
3040 |
result = (value == null) ? NIL : value; |
3041 |
postComplete(); |
3042 |
} |
3043 |
|
3044 |
/** |
3045 |
* Forcibly causes subsequent invocations of method {@link #get()} |
3046 |
* and related methods to throw the given exception, whether or |
3047 |
* not already completed. This method is designed for use only in |
3048 |
* recovery actions, and even in such situations may result in |
3049 |
* ongoing dependent completions using established versus |
3050 |
* overwritten outcomes. |
3051 |
* |
3052 |
* @param ex the exception |
3053 |
*/ |
3054 |
public void obtrudeException(Throwable ex) { |
3055 |
if (ex == null) throw new NullPointerException(); |
3056 |
result = new AltResult(ex); |
3057 |
postComplete(); |
3058 |
} |
3059 |
|
3060 |
/** |
3061 |
* Returns the estimated number of CompletableFutures whose |
3062 |
* completions are awaiting completion of this CompletableFuture. |
3063 |
* This method is designed for use in monitoring system state, not |
3064 |
* for synchronization control. |
3065 |
* |
3066 |
* @return the number of dependent CompletableFutures |
3067 |
*/ |
3068 |
public int getNumberOfDependents() { |
3069 |
int count = 0; |
3070 |
for (CompletionNode p = completions; p != null; p = p.next) |
3071 |
++count; |
3072 |
return count; |
3073 |
} |
3074 |
|
3075 |
/** |
3076 |
* Returns a string identifying this CompletableFuture, as well as |
3077 |
* its completion state. The state, in brackets, contains the |
3078 |
* String {@code "Completed Normally"} or the String {@code |
3079 |
* "Completed Exceptionally"}, or the String {@code "Not |
3080 |
* completed"} followed by the number of CompletableFutures |
3081 |
* dependent upon its completion, if any. |
3082 |
* |
3083 |
* @return a string identifying this CompletableFuture, as well as its state |
3084 |
*/ |
3085 |
public String toString() { |
3086 |
Object r = result; |
3087 |
int count; |
3088 |
return super.toString() + |
3089 |
((r == null) ? |
3090 |
(((count = getNumberOfDependents()) == 0) ? |
3091 |
"[Not completed]" : |
3092 |
"[Not completed, " + count + " dependents]") : |
3093 |
(((r instanceof AltResult) && ((AltResult)r).ex != null) ? |
3094 |
"[Completed exceptionally]" : |
3095 |
"[Completed normally]")); |
3096 |
} |
3097 |
|
3098 |
// Unsafe mechanics |
3099 |
private static final sun.misc.Unsafe UNSAFE; |
3100 |
private static final long RESULT; |
3101 |
private static final long WAITERS; |
3102 |
private static final long COMPLETIONS; |
3103 |
static { |
3104 |
try { |
3105 |
UNSAFE = sun.misc.Unsafe.getUnsafe(); |
3106 |
Class<?> k = CompletableFuture.class; |
3107 |
RESULT = UNSAFE.objectFieldOffset |
3108 |
(k.getDeclaredField("result")); |
3109 |
WAITERS = UNSAFE.objectFieldOffset |
3110 |
(k.getDeclaredField("waiters")); |
3111 |
COMPLETIONS = UNSAFE.objectFieldOffset |
3112 |
(k.getDeclaredField("completions")); |
3113 |
} catch (Exception e) { |
3114 |
throw new Error(e); |
3115 |
} |
3116 |
} |
3117 |
} |