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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.CompletionException; |
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import java.util.concurrent.CompletionStage; |
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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 be used as a {@link CompletionStage}, |
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* supporting dependent functions and actions that trigger upon its |
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* 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>In addition to these and related methods for directly |
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* manipulating status and results, CompletableFuture implements |
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* interface {@link CompletionStage} with the following policies: <ul> |
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* |
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* <li>Actions supplied for dependent completions of |
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* <em>non-async</em> methods 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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* a completion method.</li> |
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* |
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* <li>All <em>async</em> methods without an explicit Executor |
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* argument are performed using the {@link ForkJoinPool#commonPool()} |
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* (unless it does not support a parallelism level of at least two, in |
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* which case, a new Thread is used). To simplify monitoring, |
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* debugging, and tracking, all generated asynchronous tasks are |
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* instances of the marker interface {@link |
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* AsynchronousCompletionTask}. </li> |
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* |
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* <li>All CompletionStage methods are implemented independently of |
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* other public methods, so the behavior of one method is not impacted |
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* by overrides of others in subclasses. </li> </ul> |
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* |
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* <p>CompletableFuture also implements {@link Future} with the following |
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* policies: <ul> |
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* |
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* <li>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 |
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* completion. Method {@link #cancel cancel} has the same effect as |
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* {@code completeExceptionally(new CancellationException())}. Method |
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* {@link #isCompletedExceptionally} can be used to determine if a |
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* CompletableFuture completed in any exceptional fashion.</li> |
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* |
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* <li>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. To simplify usage in most |
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* contexts, this class also defines methods {@link #join()} and |
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* {@link #getNow} that instead throw the CompletionException directly |
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* in these cases.</li> </ul> |
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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>, CompletionStage<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.trigger 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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* 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 setInternalResult(T 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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} |
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|
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/** |
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* Removes and signals all waiting threads. |
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*/ |
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final void removeAndSignalWaiters() { |
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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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|
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/** |
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* Triggers all enabled completions reachable from b. Loopifies |
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* the final recursive call for each stage to avoid potential |
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* StackOverflowErrors in cases of long linear chains. |
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* |
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* @param b if non-null, a completed CompletableFuture |
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*/ |
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static final void removeAndTriggerCompletions(CompletableFuture<?> b) { |
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CompletionNode h; Completion c; CompletableFuture<?> f; |
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while (b != null && (h = b.completions) != null) { |
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if (UNSAFE.compareAndSwapObject(b, COMPLETIONS, h, h.next) && |
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(c = h.completion) != null && |
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(f = c.trigger()) != null && |
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f.result != null) { |
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f.removeAndSignalWaiters(); |
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if (f.completions != null) { |
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if (b.completions == null) |
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b = f; // tail-recurse |
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else |
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removeAndTriggerCompletions(f); |
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} |
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} |
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} |
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} |
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|
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/** |
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* Sets result, signals waiters, and triggers dependents. |
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*/ |
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final void internalComplete(T v, Throwable ex) { |
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setInternalResult(v, ex); |
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removeAndSignalWaiters(); |
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removeAndTriggerCompletions(this); |
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} |
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|
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|
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/** |
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* Signals waiters and triggers dependents. Call only if known to |
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* be completed. |
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*/ |
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final void postComplete() { |
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removeAndSignalWaiters(); |
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removeAndTriggerCompletions(this); |
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} |
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|
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/** |
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* If completed, helps signal waiters and trigger dependents. |
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*/ |
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final void helpPostComplete() { |
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if (result != null) { |
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removeAndSignalWaiters(); |
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removeAndTriggerCompletions(this); |
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} |
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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() { |
277 |
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) |
282 |
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 |
289 |
* interrupted. |
290 |
*/ |
291 |
private Object waitingGet(boolean interruptible) { |
292 |
WaitNode q = null; |
293 |
boolean queued = false; |
294 |
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 |
298 |
q.thread = null; |
299 |
if (q.interruptControl < 0) { |
300 |
if (interruptible) { |
301 |
removeWaiter(q); |
302 |
return null; |
303 |
} |
304 |
Thread.currentThread().interrupt(); |
305 |
} |
306 |
} |
307 |
postComplete(); // help release others |
308 |
return r; |
309 |
} |
310 |
else if (spins > 0) { |
311 |
int rnd = ThreadLocalRandom.nextSecondarySeed(); |
312 |
if (rnd == 0) |
313 |
rnd = ThreadLocalRandom.current().nextInt(); |
314 |
if (rnd >= 0) |
315 |
--spins; |
316 |
} |
317 |
else if (q == null) |
318 |
q = new WaitNode(interruptible, 0L, 0L); |
319 |
else if (!queued) |
320 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
321 |
q.next = waiters, q); |
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else if (interruptible && q.interruptControl < 0) { |
323 |
removeWaiter(q); |
324 |
return null; |
325 |
} |
326 |
else if (q.thread != null && result == null) { |
327 |
try { |
328 |
ForkJoinPool.managedBlock(q); |
329 |
} catch (InterruptedException ex) { |
330 |
q.interruptControl = -1; |
331 |
} |
332 |
} |
333 |
} |
334 |
} |
335 |
|
336 |
/** |
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* Awaits completion or aborts on interrupt or timeout. |
338 |
* |
339 |
* @param nanos time to wait |
340 |
* @return raw result |
341 |
*/ |
342 |
private Object timedAwaitDone(long nanos) |
343 |
throws InterruptedException, TimeoutException { |
344 |
WaitNode q = null; |
345 |
boolean queued = false; |
346 |
for (Object r;;) { |
347 |
if ((r = result) != null) { |
348 |
if (q != null) { |
349 |
q.thread = null; |
350 |
if (q.interruptControl < 0) { |
351 |
removeWaiter(q); |
352 |
throw new InterruptedException(); |
353 |
} |
354 |
} |
355 |
postComplete(); |
356 |
return r; |
357 |
} |
358 |
else if (q == null) { |
359 |
if (nanos <= 0L) |
360 |
throw new TimeoutException(); |
361 |
long d = System.nanoTime() + nanos; |
362 |
q = new WaitNode(true, nanos, d == 0L ? 1L : d); // avoid 0 |
363 |
} |
364 |
else if (!queued) |
365 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
366 |
q.next = waiters, q); |
367 |
else if (q.interruptControl < 0) { |
368 |
removeWaiter(q); |
369 |
throw new InterruptedException(); |
370 |
} |
371 |
else if (q.nanos <= 0L) { |
372 |
if (result == null) { |
373 |
removeWaiter(q); |
374 |
throw new TimeoutException(); |
375 |
} |
376 |
} |
377 |
else if (q.thread != null && result == null) { |
378 |
try { |
379 |
ForkJoinPool.managedBlock(q); |
380 |
} catch (InterruptedException ex) { |
381 |
q.interruptControl = -1; |
382 |
} |
383 |
} |
384 |
} |
385 |
} |
386 |
|
387 |
/** |
388 |
* Tries to unlink a timed-out or interrupted wait node to avoid |
389 |
* accumulating garbage. Internal nodes are simply unspliced |
390 |
* without CAS since it is harmless if they are traversed anyway |
391 |
* by releasers. To avoid effects of unsplicing from already |
392 |
* removed nodes, the list is retraversed in case of an apparent |
393 |
* race. This is slow when there are a lot of nodes, but we don't |
394 |
* expect lists to be long enough to outweigh higher-overhead |
395 |
* schemes. |
396 |
*/ |
397 |
private void removeWaiter(WaitNode node) { |
398 |
if (node != null) { |
399 |
node.thread = null; |
400 |
retry: |
401 |
for (;;) { // restart on removeWaiter race |
402 |
for (WaitNode pred = null, q = waiters, s; q != null; q = s) { |
403 |
s = q.next; |
404 |
if (q.thread != null) |
405 |
pred = q; |
406 |
else if (pred != null) { |
407 |
pred.next = s; |
408 |
if (pred.thread == null) // check for race |
409 |
continue retry; |
410 |
} |
411 |
else if (!UNSAFE.compareAndSwapObject(this, WAITERS, q, s)) |
412 |
continue retry; |
413 |
} |
414 |
break; |
415 |
} |
416 |
} |
417 |
} |
418 |
|
419 |
/* ------------- Async tasks -------------- */ |
420 |
|
421 |
/** |
422 |
* A marker interface identifying asynchronous tasks produced by |
423 |
* {@code async} methods. This may be useful for monitoring, |
424 |
* debugging, and tracking asynchronous activities. |
425 |
* |
426 |
* @since 1.8 |
427 |
*/ |
428 |
public static interface AsynchronousCompletionTask { |
429 |
} |
430 |
|
431 |
/** Base class can act as either FJ or plain Runnable */ |
432 |
@SuppressWarnings("serial") |
433 |
abstract static class Async extends ForkJoinTask<Void> |
434 |
implements Runnable, AsynchronousCompletionTask { |
435 |
public final Void getRawResult() { return null; } |
436 |
public final void setRawResult(Void v) { } |
437 |
public final void run() { exec(); } |
438 |
} |
439 |
|
440 |
/** |
441 |
* Starts the given async task using the given executor, unless |
442 |
* the executor is ForkJoinPool.commonPool and it has been |
443 |
* disabled, in which case starts a new thread. |
444 |
*/ |
445 |
static void execAsync(Executor e, Async r) { |
446 |
if (e == ForkJoinPool.commonPool() && |
447 |
ForkJoinPool.getCommonPoolParallelism() <= 1) |
448 |
new Thread(r).start(); |
449 |
else |
450 |
e.execute(r); |
451 |
} |
452 |
|
453 |
static final class AsyncRun extends Async { |
454 |
final Runnable fn; |
455 |
final CompletableFuture<Void> dst; |
456 |
AsyncRun(Runnable fn, CompletableFuture<Void> dst) { |
457 |
this.fn = fn; this.dst = dst; |
458 |
} |
459 |
public final boolean exec() { |
460 |
CompletableFuture<Void> d; Throwable ex; |
461 |
if ((d = this.dst) != null && d.result == null) { |
462 |
try { |
463 |
fn.run(); |
464 |
ex = null; |
465 |
} catch (Throwable rex) { |
466 |
ex = rex; |
467 |
} |
468 |
d.internalComplete(null, ex); |
469 |
} |
470 |
return true; |
471 |
} |
472 |
private static final long serialVersionUID = 5232453952276885070L; |
473 |
} |
474 |
|
475 |
static final class AsyncSupply<U> extends Async { |
476 |
final Supplier<U> fn; |
477 |
final CompletableFuture<U> dst; |
478 |
AsyncSupply(Supplier<U> fn, CompletableFuture<U> dst) { |
479 |
this.fn = fn; this.dst = dst; |
480 |
} |
481 |
public final boolean exec() { |
482 |
CompletableFuture<U> d; U u; Throwable ex; |
483 |
if ((d = this.dst) != null && d.result == null) { |
484 |
try { |
485 |
u = fn.get(); |
486 |
ex = null; |
487 |
} catch (Throwable rex) { |
488 |
ex = rex; |
489 |
u = null; |
490 |
} |
491 |
d.internalComplete(u, ex); |
492 |
} |
493 |
return true; |
494 |
} |
495 |
private static final long serialVersionUID = 5232453952276885070L; |
496 |
} |
497 |
|
498 |
static final class AsyncApply<T,U> extends Async { |
499 |
final T arg; |
500 |
final Function<? super T,? extends U> fn; |
501 |
final CompletableFuture<U> dst; |
502 |
AsyncApply(T arg, Function<? super T,? extends U> fn, |
503 |
CompletableFuture<U> dst) { |
504 |
this.arg = arg; this.fn = fn; this.dst = dst; |
505 |
} |
506 |
public final boolean exec() { |
507 |
CompletableFuture<U> d; U u; Throwable ex; |
508 |
if ((d = this.dst) != null && d.result == null) { |
509 |
try { |
510 |
u = fn.apply(arg); |
511 |
ex = null; |
512 |
} catch (Throwable rex) { |
513 |
ex = rex; |
514 |
u = null; |
515 |
} |
516 |
d.internalComplete(u, ex); |
517 |
} |
518 |
return true; |
519 |
} |
520 |
private static final long serialVersionUID = 5232453952276885070L; |
521 |
} |
522 |
|
523 |
static final class AsyncCombine<T,U,V> extends Async { |
524 |
final T arg1; |
525 |
final U arg2; |
526 |
final BiFunction<? super T,? super U,? extends V> fn; |
527 |
final CompletableFuture<V> dst; |
528 |
AsyncCombine(T arg1, U arg2, |
529 |
BiFunction<? super T,? super U,? extends V> fn, |
530 |
CompletableFuture<V> dst) { |
531 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
532 |
} |
533 |
public final boolean exec() { |
534 |
CompletableFuture<V> d; V v; Throwable ex; |
535 |
if ((d = this.dst) != null && d.result == null) { |
536 |
try { |
537 |
v = fn.apply(arg1, arg2); |
538 |
ex = null; |
539 |
} catch (Throwable rex) { |
540 |
ex = rex; |
541 |
v = null; |
542 |
} |
543 |
d.internalComplete(v, ex); |
544 |
} |
545 |
return true; |
546 |
} |
547 |
private static final long serialVersionUID = 5232453952276885070L; |
548 |
} |
549 |
|
550 |
static final class AsyncAccept<T> extends Async { |
551 |
final T arg; |
552 |
final Consumer<? super T> fn; |
553 |
final CompletableFuture<?> dst; |
554 |
AsyncAccept(T arg, Consumer<? super T> fn, |
555 |
CompletableFuture<?> dst) { |
556 |
this.arg = arg; this.fn = fn; this.dst = dst; |
557 |
} |
558 |
public final boolean exec() { |
559 |
CompletableFuture<?> d; Throwable ex; |
560 |
if ((d = this.dst) != null && d.result == null) { |
561 |
try { |
562 |
fn.accept(arg); |
563 |
ex = null; |
564 |
} catch (Throwable rex) { |
565 |
ex = rex; |
566 |
} |
567 |
d.internalComplete(null, ex); |
568 |
} |
569 |
return true; |
570 |
} |
571 |
private static final long serialVersionUID = 5232453952276885070L; |
572 |
} |
573 |
|
574 |
static final class AsyncAcceptBoth<T,U> extends Async { |
575 |
final T arg1; |
576 |
final U arg2; |
577 |
final BiConsumer<? super T,? super U> fn; |
578 |
final CompletableFuture<?> dst; |
579 |
AsyncAcceptBoth(T arg1, U arg2, |
580 |
BiConsumer<? super T,? super U> fn, |
581 |
CompletableFuture<?> dst) { |
582 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
583 |
} |
584 |
public final boolean exec() { |
585 |
CompletableFuture<?> d; Throwable ex; |
586 |
if ((d = this.dst) != null && d.result == null) { |
587 |
try { |
588 |
fn.accept(arg1, arg2); |
589 |
ex = null; |
590 |
} catch (Throwable rex) { |
591 |
ex = rex; |
592 |
} |
593 |
d.internalComplete(null, ex); |
594 |
} |
595 |
return true; |
596 |
} |
597 |
private static final long serialVersionUID = 5232453952276885070L; |
598 |
} |
599 |
|
600 |
static final class AsyncCompose<T,U> extends Async { |
601 |
final T arg; |
602 |
final Function<? super T, ? extends CompletionStage<U>> fn; |
603 |
final CompletableFuture<U> dst; |
604 |
AsyncCompose(T arg, |
605 |
Function<? super T, ? extends CompletionStage<U>> fn, |
606 |
CompletableFuture<U> dst) { |
607 |
this.arg = arg; this.fn = fn; this.dst = dst; |
608 |
} |
609 |
public final boolean exec() { |
610 |
CompletableFuture<U> d, fr; U u; Throwable ex; |
611 |
if ((d = this.dst) != null && d.result == null) { |
612 |
try { |
613 |
CompletionStage<U> cs = fn.apply(arg); |
614 |
fr = (cs == null) ? null : cs.toCompletableFuture(); |
615 |
ex = (fr == null) ? new NullPointerException() : null; |
616 |
} catch (Throwable rex) { |
617 |
ex = rex; |
618 |
fr = null; |
619 |
} |
620 |
if (ex != null) |
621 |
u = null; |
622 |
else { |
623 |
Object r = fr.result; |
624 |
if (r == null) |
625 |
r = fr.waitingGet(false); |
626 |
if (r instanceof AltResult) { |
627 |
ex = ((AltResult)r).ex; |
628 |
u = null; |
629 |
} |
630 |
else { |
631 |
@SuppressWarnings("unchecked") U ur = (U) r; |
632 |
u = ur; |
633 |
} |
634 |
} |
635 |
d.internalComplete(u, ex); |
636 |
} |
637 |
return true; |
638 |
} |
639 |
private static final long serialVersionUID = 5232453952276885070L; |
640 |
} |
641 |
|
642 |
static final class AsyncWhenComplete<T> extends Async { |
643 |
final T arg1; |
644 |
final Throwable arg2; |
645 |
final BiConsumer<? super T,? super Throwable> fn; |
646 |
final CompletableFuture<T> dst; |
647 |
AsyncWhenComplete(T arg1, Throwable arg2, |
648 |
BiConsumer<? super T,? super Throwable> fn, |
649 |
CompletableFuture<T> dst) { |
650 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
651 |
} |
652 |
public final boolean exec() { |
653 |
CompletableFuture<T> d; |
654 |
if ((d = this.dst) != null && d.result == null) { |
655 |
Throwable ex = arg2; |
656 |
try { |
657 |
fn.accept(arg1, ex); |
658 |
} catch (Throwable rex) { |
659 |
if (ex == null) |
660 |
ex = rex; |
661 |
} |
662 |
d.internalComplete(arg1, ex); |
663 |
} |
664 |
return true; |
665 |
} |
666 |
private static final long serialVersionUID = 5232453952276885070L; |
667 |
} |
668 |
|
669 |
/* ------------- Completions -------------- */ |
670 |
|
671 |
/** |
672 |
* Simple linked list nodes to record completions, used in |
673 |
* basically the same way as WaitNodes. (We separate nodes from |
674 |
* the Completions themselves mainly because for the And and Or |
675 |
* methods, the same Completion object resides in two lists.) |
676 |
*/ |
677 |
static final class CompletionNode { |
678 |
final Completion completion; |
679 |
volatile CompletionNode next; |
680 |
CompletionNode(Completion completion) { this.completion = completion; } |
681 |
} |
682 |
|
683 |
// Opportunistically subclass AtomicInteger to use compareAndSet to claim. |
684 |
@SuppressWarnings("serial") |
685 |
abstract static class Completion extends AtomicInteger { |
686 |
/** |
687 |
* Complete a dependent Completablefuture if enabled |
688 |
* @return the dependent Completablefuture |
689 |
*/ |
690 |
public abstract CompletableFuture<?> trigger(); |
691 |
} |
692 |
|
693 |
static final class ThenApply<T,U> extends Completion { |
694 |
final CompletableFuture<? extends T> src; |
695 |
final Function<? super T,? extends U> fn; |
696 |
final CompletableFuture<U> dst; |
697 |
final Executor executor; |
698 |
ThenApply(CompletableFuture<? extends T> src, |
699 |
Function<? super T,? extends U> fn, |
700 |
CompletableFuture<U> dst, |
701 |
Executor executor) { |
702 |
this.src = src; this.fn = fn; this.dst = dst; |
703 |
this.executor = executor; |
704 |
} |
705 |
public final CompletableFuture<?> trigger() { |
706 |
final CompletableFuture<? extends T> a; |
707 |
final Function<? super T,? extends U> fn; |
708 |
final CompletableFuture<U> dst; |
709 |
Object r; T t; Throwable ex; |
710 |
if ((dst = this.dst) != null && |
711 |
(fn = this.fn) != null && |
712 |
(a = this.src) != null && |
713 |
(r = a.result) != null && |
714 |
compareAndSet(0, 1)) { |
715 |
if (r instanceof AltResult) { |
716 |
ex = ((AltResult)r).ex; |
717 |
t = null; |
718 |
} |
719 |
else { |
720 |
ex = null; |
721 |
@SuppressWarnings("unchecked") T tr = (T) r; |
722 |
t = tr; |
723 |
} |
724 |
Executor e = executor; |
725 |
U u = null; |
726 |
if (ex == null) { |
727 |
try { |
728 |
if (e != null) |
729 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
730 |
else |
731 |
u = fn.apply(t); |
732 |
} catch (Throwable rex) { |
733 |
ex = rex; |
734 |
} |
735 |
} |
736 |
if (e == null || ex != null) |
737 |
dst.setInternalResult(u, ex); |
738 |
} |
739 |
return dst; |
740 |
} |
741 |
private static final long serialVersionUID = 5232453952276885070L; |
742 |
} |
743 |
|
744 |
static final class ThenAccept<T> extends Completion { |
745 |
final CompletableFuture<? extends T> src; |
746 |
final Consumer<? super T> fn; |
747 |
final CompletableFuture<?> dst; |
748 |
final Executor executor; |
749 |
ThenAccept(CompletableFuture<? extends T> src, |
750 |
Consumer<? super T> fn, |
751 |
CompletableFuture<?> dst, |
752 |
Executor executor) { |
753 |
this.src = src; this.fn = fn; this.dst = dst; |
754 |
this.executor = executor; |
755 |
} |
756 |
public final CompletableFuture<?> trigger() { |
757 |
final CompletableFuture<? extends T> a; |
758 |
final Consumer<? super T> fn; |
759 |
final CompletableFuture<?> dst; |
760 |
Object r; T t; Throwable ex; |
761 |
if ((dst = this.dst) != null && |
762 |
(fn = this.fn) != null && |
763 |
(a = this.src) != null && |
764 |
(r = a.result) != null && |
765 |
compareAndSet(0, 1)) { |
766 |
if (r instanceof AltResult) { |
767 |
ex = ((AltResult)r).ex; |
768 |
t = null; |
769 |
} |
770 |
else { |
771 |
ex = null; |
772 |
@SuppressWarnings("unchecked") T tr = (T) r; |
773 |
t = tr; |
774 |
} |
775 |
Executor e = executor; |
776 |
if (ex == null) { |
777 |
try { |
778 |
if (e != null) |
779 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
780 |
else |
781 |
fn.accept(t); |
782 |
} catch (Throwable rex) { |
783 |
ex = rex; |
784 |
} |
785 |
} |
786 |
if (e == null || ex != null) |
787 |
dst.setInternalResult(null, ex); |
788 |
} |
789 |
return dst; |
790 |
} |
791 |
private static final long serialVersionUID = 5232453952276885070L; |
792 |
} |
793 |
|
794 |
static final class ThenRun extends Completion { |
795 |
final CompletableFuture<?> src; |
796 |
final Runnable fn; |
797 |
final CompletableFuture<Void> dst; |
798 |
final Executor executor; |
799 |
ThenRun(CompletableFuture<?> src, |
800 |
Runnable fn, |
801 |
CompletableFuture<Void> dst, |
802 |
Executor executor) { |
803 |
this.src = src; this.fn = fn; this.dst = dst; |
804 |
this.executor = executor; |
805 |
} |
806 |
public final CompletableFuture<?> trigger() { |
807 |
final CompletableFuture<?> a; |
808 |
final Runnable fn; |
809 |
final CompletableFuture<Void> dst; |
810 |
Object r; Throwable ex; |
811 |
if ((dst = this.dst) != null && |
812 |
(fn = this.fn) != null && |
813 |
(a = this.src) != null && |
814 |
(r = a.result) != null && |
815 |
compareAndSet(0, 1)) { |
816 |
if (r instanceof AltResult) |
817 |
ex = ((AltResult)r).ex; |
818 |
else |
819 |
ex = null; |
820 |
Executor e = executor; |
821 |
if (ex == null) { |
822 |
try { |
823 |
if (e != null) |
824 |
execAsync(e, new AsyncRun(fn, dst)); |
825 |
else |
826 |
fn.run(); |
827 |
} catch (Throwable rex) { |
828 |
ex = rex; |
829 |
} |
830 |
} |
831 |
if (e == null || ex != null) |
832 |
dst.setInternalResult(null, ex); |
833 |
} |
834 |
return dst; |
835 |
} |
836 |
private static final long serialVersionUID = 5232453952276885070L; |
837 |
} |
838 |
|
839 |
static final class ThenCombine<T,U,V> extends Completion { |
840 |
final CompletableFuture<? extends T> src; |
841 |
final CompletableFuture<? extends U> snd; |
842 |
final BiFunction<? super T,? super U,? extends V> fn; |
843 |
final CompletableFuture<V> dst; |
844 |
final Executor executor; |
845 |
ThenCombine(CompletableFuture<? extends T> src, |
846 |
CompletableFuture<? extends U> snd, |
847 |
BiFunction<? super T,? super U,? extends V> fn, |
848 |
CompletableFuture<V> dst, |
849 |
Executor executor) { |
850 |
this.src = src; this.snd = snd; |
851 |
this.fn = fn; this.dst = dst; |
852 |
this.executor = executor; |
853 |
} |
854 |
public final CompletableFuture<?> trigger() { |
855 |
final CompletableFuture<? extends T> a; |
856 |
final CompletableFuture<? extends U> b; |
857 |
final BiFunction<? super T,? super U,? extends V> fn; |
858 |
final CompletableFuture<V> dst; |
859 |
Object r, s; T t; U u; Throwable ex; |
860 |
if ((dst = this.dst) != null && |
861 |
(fn = this.fn) != null && |
862 |
(a = this.src) != null && |
863 |
(r = a.result) != null && |
864 |
(b = this.snd) != null && |
865 |
(s = b.result) != null && |
866 |
compareAndSet(0, 1)) { |
867 |
if (r instanceof AltResult) { |
868 |
ex = ((AltResult)r).ex; |
869 |
t = null; |
870 |
} |
871 |
else { |
872 |
ex = null; |
873 |
@SuppressWarnings("unchecked") T tr = (T) r; |
874 |
t = tr; |
875 |
} |
876 |
if (ex != null) |
877 |
u = null; |
878 |
else if (s instanceof AltResult) { |
879 |
ex = ((AltResult)s).ex; |
880 |
u = null; |
881 |
} |
882 |
else { |
883 |
@SuppressWarnings("unchecked") U us = (U) s; |
884 |
u = us; |
885 |
} |
886 |
Executor e = executor; |
887 |
V v = null; |
888 |
if (ex == null) { |
889 |
try { |
890 |
if (e != null) |
891 |
execAsync(e, new AsyncCombine<T,U,V>(t, u, fn, dst)); |
892 |
else |
893 |
v = fn.apply(t, u); |
894 |
} catch (Throwable rex) { |
895 |
ex = rex; |
896 |
} |
897 |
} |
898 |
if (e == null || ex != null) |
899 |
dst.setInternalResult(v, ex); |
900 |
} |
901 |
return dst; |
902 |
} |
903 |
private static final long serialVersionUID = 5232453952276885070L; |
904 |
} |
905 |
|
906 |
static final class ThenAcceptBoth<T,U> extends Completion { |
907 |
final CompletableFuture<? extends T> src; |
908 |
final CompletableFuture<? extends U> snd; |
909 |
final BiConsumer<? super T,? super U> fn; |
910 |
final CompletableFuture<Void> dst; |
911 |
final Executor executor; |
912 |
ThenAcceptBoth(CompletableFuture<? extends T> src, |
913 |
CompletableFuture<? extends U> snd, |
914 |
BiConsumer<? super T,? super U> fn, |
915 |
CompletableFuture<Void> dst, |
916 |
Executor executor) { |
917 |
this.src = src; this.snd = snd; |
918 |
this.fn = fn; this.dst = dst; |
919 |
this.executor = executor; |
920 |
} |
921 |
public final CompletableFuture<?> trigger() { |
922 |
final CompletableFuture<? extends T> a; |
923 |
final CompletableFuture<? extends U> b; |
924 |
final BiConsumer<? super T,? super U> fn; |
925 |
final CompletableFuture<Void> dst; |
926 |
Object r, s; T t; U u; Throwable ex; |
927 |
if ((dst = this.dst) != null && |
928 |
(fn = this.fn) != null && |
929 |
(a = this.src) != null && |
930 |
(r = a.result) != null && |
931 |
(b = this.snd) != null && |
932 |
(s = b.result) != null && |
933 |
compareAndSet(0, 1)) { |
934 |
if (r instanceof AltResult) { |
935 |
ex = ((AltResult)r).ex; |
936 |
t = null; |
937 |
} |
938 |
else { |
939 |
ex = null; |
940 |
@SuppressWarnings("unchecked") T tr = (T) r; |
941 |
t = tr; |
942 |
} |
943 |
if (ex != null) |
944 |
u = null; |
945 |
else if (s instanceof AltResult) { |
946 |
ex = ((AltResult)s).ex; |
947 |
u = null; |
948 |
} |
949 |
else { |
950 |
@SuppressWarnings("unchecked") U us = (U) s; |
951 |
u = us; |
952 |
} |
953 |
Executor e = executor; |
954 |
if (ex == null) { |
955 |
try { |
956 |
if (e != null) |
957 |
execAsync(e, new AsyncAcceptBoth<T,U>(t, u, fn, dst)); |
958 |
else |
959 |
fn.accept(t, u); |
960 |
} catch (Throwable rex) { |
961 |
ex = rex; |
962 |
} |
963 |
} |
964 |
if (e == null || ex != null) |
965 |
dst.setInternalResult(null, ex); |
966 |
} |
967 |
return dst; |
968 |
} |
969 |
private static final long serialVersionUID = 5232453952276885070L; |
970 |
} |
971 |
|
972 |
static final class RunAfterBoth extends Completion { |
973 |
final CompletableFuture<?> src; |
974 |
final CompletableFuture<?> snd; |
975 |
final Runnable fn; |
976 |
final CompletableFuture<Void> dst; |
977 |
final Executor executor; |
978 |
RunAfterBoth(CompletableFuture<?> src, |
979 |
CompletableFuture<?> snd, |
980 |
Runnable fn, |
981 |
CompletableFuture<Void> dst, |
982 |
Executor executor) { |
983 |
this.src = src; this.snd = snd; |
984 |
this.fn = fn; this.dst = dst; |
985 |
this.executor = executor; |
986 |
} |
987 |
public final CompletableFuture<?> trigger() { |
988 |
final CompletableFuture<?> a; |
989 |
final CompletableFuture<?> b; |
990 |
final Runnable fn; |
991 |
final CompletableFuture<Void> dst; |
992 |
Object r, s; Throwable ex; |
993 |
if ((dst = this.dst) != null && |
994 |
(fn = this.fn) != null && |
995 |
(a = this.src) != null && |
996 |
(r = a.result) != null && |
997 |
(b = this.snd) != null && |
998 |
(s = b.result) != null && |
999 |
compareAndSet(0, 1)) { |
1000 |
if (r instanceof AltResult) |
1001 |
ex = ((AltResult)r).ex; |
1002 |
else |
1003 |
ex = null; |
1004 |
if (ex == null && (s instanceof AltResult)) |
1005 |
ex = ((AltResult)s).ex; |
1006 |
Executor e = executor; |
1007 |
if (ex == null) { |
1008 |
try { |
1009 |
if (e != null) |
1010 |
execAsync(e, new AsyncRun(fn, dst)); |
1011 |
else |
1012 |
fn.run(); |
1013 |
} catch (Throwable rex) { |
1014 |
ex = rex; |
1015 |
} |
1016 |
} |
1017 |
if (e == null || ex != null) |
1018 |
dst.setInternalResult(null, ex); |
1019 |
} |
1020 |
return dst; |
1021 |
} |
1022 |
private static final long serialVersionUID = 5232453952276885070L; |
1023 |
} |
1024 |
|
1025 |
static final class AndCompletion extends Completion { |
1026 |
final CompletableFuture<?> src; |
1027 |
final CompletableFuture<?> snd; |
1028 |
final CompletableFuture<Void> dst; |
1029 |
AndCompletion(CompletableFuture<?> src, |
1030 |
CompletableFuture<?> snd, |
1031 |
CompletableFuture<Void> dst) { |
1032 |
this.src = src; this.snd = snd; this.dst = dst; |
1033 |
} |
1034 |
public final CompletableFuture<?> trigger() { |
1035 |
final CompletableFuture<?> a; |
1036 |
final CompletableFuture<?> b; |
1037 |
final CompletableFuture<Void> dst; |
1038 |
Object r, s; Throwable ex; |
1039 |
if ((dst = this.dst) != null && |
1040 |
(a = this.src) != null && |
1041 |
(r = a.result) != null && |
1042 |
(b = this.snd) != null && |
1043 |
(s = b.result) != null && |
1044 |
compareAndSet(0, 1)) { |
1045 |
if (r instanceof AltResult) |
1046 |
ex = ((AltResult)r).ex; |
1047 |
else |
1048 |
ex = null; |
1049 |
if (ex == null && (s instanceof AltResult)) |
1050 |
ex = ((AltResult)s).ex; |
1051 |
dst.setInternalResult(null, ex); |
1052 |
} |
1053 |
return dst; |
1054 |
} |
1055 |
private static final long serialVersionUID = 5232453952276885070L; |
1056 |
} |
1057 |
|
1058 |
static final class ApplyToEither<T,U> extends Completion { |
1059 |
final CompletableFuture<? extends T> src; |
1060 |
final CompletableFuture<? extends T> snd; |
1061 |
final Function<? super T,? extends U> fn; |
1062 |
final CompletableFuture<U> dst; |
1063 |
final Executor executor; |
1064 |
ApplyToEither(CompletableFuture<? extends T> src, |
1065 |
CompletableFuture<? extends T> snd, |
1066 |
Function<? super T,? extends U> fn, |
1067 |
CompletableFuture<U> dst, |
1068 |
Executor executor) { |
1069 |
this.src = src; this.snd = snd; |
1070 |
this.fn = fn; this.dst = dst; |
1071 |
this.executor = executor; |
1072 |
} |
1073 |
public final CompletableFuture<?> trigger() { |
1074 |
final CompletableFuture<? extends T> a; |
1075 |
final CompletableFuture<? extends T> b; |
1076 |
final Function<? super T,? extends U> fn; |
1077 |
final CompletableFuture<U> dst; |
1078 |
Object r; T t; Throwable ex; |
1079 |
if ((dst = this.dst) != null && |
1080 |
(fn = this.fn) != null && |
1081 |
(((a = this.src) != null && (r = a.result) != null) || |
1082 |
((b = this.snd) != null && (r = b.result) != null)) && |
1083 |
compareAndSet(0, 1)) { |
1084 |
if (r instanceof AltResult) { |
1085 |
ex = ((AltResult)r).ex; |
1086 |
t = null; |
1087 |
} |
1088 |
else { |
1089 |
ex = null; |
1090 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1091 |
t = tr; |
1092 |
} |
1093 |
Executor e = executor; |
1094 |
U u = null; |
1095 |
if (ex == null) { |
1096 |
try { |
1097 |
if (e != null) |
1098 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
1099 |
else |
1100 |
u = fn.apply(t); |
1101 |
} catch (Throwable rex) { |
1102 |
ex = rex; |
1103 |
} |
1104 |
} |
1105 |
if (e == null || ex != null) |
1106 |
dst.setInternalResult(u, ex); |
1107 |
} |
1108 |
return dst; |
1109 |
} |
1110 |
private static final long serialVersionUID = 5232453952276885070L; |
1111 |
} |
1112 |
|
1113 |
static final class AcceptEither<T> extends Completion { |
1114 |
final CompletableFuture<? extends T> src; |
1115 |
final CompletableFuture<? extends T> snd; |
1116 |
final Consumer<? super T> fn; |
1117 |
final CompletableFuture<Void> dst; |
1118 |
final Executor executor; |
1119 |
AcceptEither(CompletableFuture<? extends T> src, |
1120 |
CompletableFuture<? extends T> snd, |
1121 |
Consumer<? super T> fn, |
1122 |
CompletableFuture<Void> dst, |
1123 |
Executor executor) { |
1124 |
this.src = src; this.snd = snd; |
1125 |
this.fn = fn; this.dst = dst; |
1126 |
this.executor = executor; |
1127 |
} |
1128 |
public final CompletableFuture<?> trigger() { |
1129 |
final CompletableFuture<? extends T> a; |
1130 |
final CompletableFuture<? extends T> b; |
1131 |
final Consumer<? super T> fn; |
1132 |
final CompletableFuture<Void> dst; |
1133 |
Object r; T t; Throwable ex; |
1134 |
if ((dst = this.dst) != null && |
1135 |
(fn = this.fn) != null && |
1136 |
(((a = this.src) != null && (r = a.result) != null) || |
1137 |
((b = this.snd) != null && (r = b.result) != null)) && |
1138 |
compareAndSet(0, 1)) { |
1139 |
if (r instanceof AltResult) { |
1140 |
ex = ((AltResult)r).ex; |
1141 |
t = null; |
1142 |
} |
1143 |
else { |
1144 |
ex = null; |
1145 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1146 |
t = tr; |
1147 |
} |
1148 |
Executor e = executor; |
1149 |
if (ex == null) { |
1150 |
try { |
1151 |
if (e != null) |
1152 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
1153 |
else |
1154 |
fn.accept(t); |
1155 |
} catch (Throwable rex) { |
1156 |
ex = rex; |
1157 |
} |
1158 |
} |
1159 |
if (e == null || ex != null) |
1160 |
dst.setInternalResult(null, ex); |
1161 |
} |
1162 |
return dst; |
1163 |
} |
1164 |
private static final long serialVersionUID = 5232453952276885070L; |
1165 |
} |
1166 |
|
1167 |
static final class RunAfterEither extends Completion { |
1168 |
final CompletableFuture<?> src; |
1169 |
final CompletableFuture<?> snd; |
1170 |
final Runnable fn; |
1171 |
final CompletableFuture<Void> dst; |
1172 |
final Executor executor; |
1173 |
RunAfterEither(CompletableFuture<?> src, |
1174 |
CompletableFuture<?> snd, |
1175 |
Runnable fn, |
1176 |
CompletableFuture<Void> dst, |
1177 |
Executor executor) { |
1178 |
this.src = src; this.snd = snd; |
1179 |
this.fn = fn; this.dst = dst; |
1180 |
this.executor = executor; |
1181 |
} |
1182 |
public final CompletableFuture<?> trigger() { |
1183 |
final CompletableFuture<?> a; |
1184 |
final CompletableFuture<?> b; |
1185 |
final Runnable fn; |
1186 |
final CompletableFuture<Void> dst; |
1187 |
Object r; Throwable ex; |
1188 |
if ((dst = this.dst) != null && |
1189 |
(fn = this.fn) != null && |
1190 |
(((a = this.src) != null && (r = a.result) != null) || |
1191 |
((b = this.snd) != null && (r = b.result) != null)) && |
1192 |
compareAndSet(0, 1)) { |
1193 |
if (r instanceof AltResult) |
1194 |
ex = ((AltResult)r).ex; |
1195 |
else |
1196 |
ex = null; |
1197 |
Executor e = executor; |
1198 |
if (ex == null) { |
1199 |
try { |
1200 |
if (e != null) |
1201 |
execAsync(e, new AsyncRun(fn, dst)); |
1202 |
else |
1203 |
fn.run(); |
1204 |
} catch (Throwable rex) { |
1205 |
ex = rex; |
1206 |
} |
1207 |
} |
1208 |
if (e == null || ex != null) |
1209 |
dst.setInternalResult(null, ex); |
1210 |
} |
1211 |
return dst; |
1212 |
} |
1213 |
private static final long serialVersionUID = 5232453952276885070L; |
1214 |
} |
1215 |
|
1216 |
static final class OrCompletion extends Completion { |
1217 |
final CompletableFuture<?> src; |
1218 |
final CompletableFuture<?> snd; |
1219 |
final CompletableFuture<Object> dst; |
1220 |
OrCompletion(CompletableFuture<?> src, |
1221 |
CompletableFuture<?> snd, |
1222 |
CompletableFuture<Object> dst) { |
1223 |
this.src = src; this.snd = snd; this.dst = dst; |
1224 |
} |
1225 |
public final CompletableFuture<?> trigger() { |
1226 |
final CompletableFuture<?> a; |
1227 |
final CompletableFuture<?> b; |
1228 |
final CompletableFuture<Object> dst; |
1229 |
Object r, t; Throwable ex; |
1230 |
if ((dst = this.dst) != null && |
1231 |
(((a = this.src) != null && (r = a.result) != null) || |
1232 |
((b = this.snd) != null && (r = b.result) != null)) && |
1233 |
compareAndSet(0, 1)) { |
1234 |
if (r instanceof AltResult) { |
1235 |
ex = ((AltResult)r).ex; |
1236 |
t = null; |
1237 |
} |
1238 |
else { |
1239 |
ex = null; |
1240 |
t = r; |
1241 |
} |
1242 |
dst.setInternalResult(t, ex); |
1243 |
} |
1244 |
return dst; |
1245 |
} |
1246 |
private static final long serialVersionUID = 5232453952276885070L; |
1247 |
} |
1248 |
|
1249 |
static final class ExceptionCompletion<T> extends Completion { |
1250 |
final CompletableFuture<? extends T> src; |
1251 |
final Function<? super Throwable, ? extends T> fn; |
1252 |
final CompletableFuture<T> dst; |
1253 |
ExceptionCompletion(CompletableFuture<? extends T> src, |
1254 |
Function<? super Throwable, ? extends T> fn, |
1255 |
CompletableFuture<T> dst) { |
1256 |
this.src = src; this.fn = fn; this.dst = dst; |
1257 |
} |
1258 |
public final CompletableFuture<?> trigger() { |
1259 |
final CompletableFuture<? extends T> a; |
1260 |
final Function<? super Throwable, ? extends T> fn; |
1261 |
final CompletableFuture<T> dst; |
1262 |
Object r; T t = null; Throwable ex, dx = null; |
1263 |
if ((dst = this.dst) != null && |
1264 |
(fn = this.fn) != null && |
1265 |
(a = this.src) != null && |
1266 |
(r = a.result) != null && |
1267 |
compareAndSet(0, 1)) { |
1268 |
if ((r instanceof AltResult) && |
1269 |
(ex = ((AltResult)r).ex) != null) { |
1270 |
try { |
1271 |
t = fn.apply(ex); |
1272 |
} catch (Throwable rex) { |
1273 |
dx = rex; |
1274 |
} |
1275 |
} |
1276 |
else { |
1277 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1278 |
t = tr; |
1279 |
} |
1280 |
dst.setInternalResult(t, dx); |
1281 |
} |
1282 |
return dst; |
1283 |
} |
1284 |
private static final long serialVersionUID = 5232453952276885070L; |
1285 |
} |
1286 |
|
1287 |
static final class WhenCompleteCompletion<T> extends Completion { |
1288 |
final CompletableFuture<? extends T> src; |
1289 |
final BiConsumer<? super T, ? super Throwable> fn; |
1290 |
final CompletableFuture<T> dst; |
1291 |
final Executor executor; |
1292 |
WhenCompleteCompletion(CompletableFuture<? extends T> src, |
1293 |
BiConsumer<? super T, ? super Throwable> fn, |
1294 |
CompletableFuture<T> dst, |
1295 |
Executor executor) { |
1296 |
this.src = src; this.fn = fn; this.dst = dst; |
1297 |
this.executor = executor; |
1298 |
} |
1299 |
public final CompletableFuture<?> trigger() { |
1300 |
final CompletableFuture<? extends T> a; |
1301 |
final BiConsumer<? super T, ? super Throwable> fn; |
1302 |
final CompletableFuture<T> dst; |
1303 |
Object r; T t; Throwable ex; |
1304 |
if ((dst = this.dst) != null && |
1305 |
(fn = this.fn) != null && |
1306 |
(a = this.src) != null && |
1307 |
(r = a.result) != null && |
1308 |
compareAndSet(0, 1)) { |
1309 |
if (r instanceof AltResult) { |
1310 |
ex = ((AltResult)r).ex; |
1311 |
t = null; |
1312 |
} |
1313 |
else { |
1314 |
ex = null; |
1315 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1316 |
t = tr; |
1317 |
} |
1318 |
Executor e = executor; |
1319 |
Throwable dx = null; |
1320 |
try { |
1321 |
if (e != null) |
1322 |
execAsync(e, new AsyncWhenComplete<T>(t, ex, fn, dst)); |
1323 |
else |
1324 |
fn.accept(t, ex); |
1325 |
} catch (Throwable rex) { |
1326 |
dx = rex; |
1327 |
} |
1328 |
if (e == null || dx != null) |
1329 |
dst.setInternalResult(t, ex != null ? ex : dx); |
1330 |
} |
1331 |
return dst; |
1332 |
} |
1333 |
private static final long serialVersionUID = 5232453952276885070L; |
1334 |
} |
1335 |
|
1336 |
static final class ThenCopy<T> extends Completion { |
1337 |
final CompletableFuture<?> src; |
1338 |
final CompletableFuture<T> dst; |
1339 |
ThenCopy(CompletableFuture<?> src, |
1340 |
CompletableFuture<T> dst) { |
1341 |
this.src = src; this.dst = dst; |
1342 |
} |
1343 |
public final CompletableFuture<?> trigger() { |
1344 |
final CompletableFuture<?> a; |
1345 |
final CompletableFuture<T> dst; |
1346 |
Object r; T t; Throwable ex; |
1347 |
if ((dst = this.dst) != null && |
1348 |
(a = this.src) != null && |
1349 |
(r = a.result) != null && |
1350 |
compareAndSet(0, 1)) { |
1351 |
if (r instanceof AltResult) { |
1352 |
ex = ((AltResult)r).ex; |
1353 |
t = null; |
1354 |
} |
1355 |
else { |
1356 |
ex = null; |
1357 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1358 |
t = tr; |
1359 |
} |
1360 |
dst.setInternalResult(t, ex); |
1361 |
} |
1362 |
return dst; |
1363 |
} |
1364 |
private static final long serialVersionUID = 5232453952276885070L; |
1365 |
} |
1366 |
|
1367 |
// version of ThenCopy for CompletableFuture<Void> dst |
1368 |
static final class ThenPropagate extends Completion { |
1369 |
final CompletableFuture<?> src; |
1370 |
final CompletableFuture<Void> dst; |
1371 |
ThenPropagate(CompletableFuture<?> src, |
1372 |
CompletableFuture<Void> dst) { |
1373 |
this.src = src; this.dst = dst; |
1374 |
} |
1375 |
public final CompletableFuture<?> trigger() { |
1376 |
final CompletableFuture<?> a; |
1377 |
final CompletableFuture<Void> dst; |
1378 |
Object r; Throwable ex; |
1379 |
if ((dst = this.dst) != null && |
1380 |
(a = this.src) != null && |
1381 |
(r = a.result) != null && |
1382 |
compareAndSet(0, 1)) { |
1383 |
if (r instanceof AltResult) |
1384 |
ex = ((AltResult)r).ex; |
1385 |
else |
1386 |
ex = null; |
1387 |
dst.setInternalResult(null, ex); |
1388 |
} |
1389 |
return dst; |
1390 |
} |
1391 |
private static final long serialVersionUID = 5232453952276885070L; |
1392 |
} |
1393 |
|
1394 |
static final class HandleCompletion<T,U> extends Completion { |
1395 |
final CompletableFuture<? extends T> src; |
1396 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1397 |
final CompletableFuture<U> dst; |
1398 |
final Executor executor; |
1399 |
HandleCompletion(CompletableFuture<? extends T> src, |
1400 |
BiFunction<? super T, Throwable, ? extends U> fn, |
1401 |
CompletableFuture<U> dst, |
1402 |
Executor executor) { |
1403 |
this.src = src; this.fn = fn; this.dst = dst; |
1404 |
this.executor = executor; |
1405 |
} |
1406 |
public final CompletableFuture<?> trigger() { |
1407 |
final CompletableFuture<? extends T> a; |
1408 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1409 |
final CompletableFuture<U> dst; |
1410 |
Object r; T t; Throwable ex; |
1411 |
if ((dst = this.dst) != null && |
1412 |
(fn = this.fn) != null && |
1413 |
(a = this.src) != null && |
1414 |
(r = a.result) != null && |
1415 |
compareAndSet(0, 1)) { |
1416 |
if (r instanceof AltResult) { |
1417 |
ex = ((AltResult)r).ex; |
1418 |
t = null; |
1419 |
} |
1420 |
else { |
1421 |
ex = null; |
1422 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1423 |
t = tr; |
1424 |
} |
1425 |
Executor e = executor; |
1426 |
U u = null; |
1427 |
Throwable dx = null; |
1428 |
try { |
1429 |
if (e != null) |
1430 |
execAsync(e, new AsyncCombine<T,Throwable,U>(t, ex, fn, dst)); |
1431 |
else |
1432 |
u = fn.apply(t, ex); |
1433 |
} catch (Throwable rex) { |
1434 |
dx = rex; |
1435 |
} |
1436 |
if (e == null || dx != null) |
1437 |
dst.setInternalResult(u, dx); |
1438 |
} |
1439 |
return dst; |
1440 |
} |
1441 |
private static final long serialVersionUID = 5232453952276885070L; |
1442 |
} |
1443 |
|
1444 |
static final class ThenCompose<T,U> extends Completion { |
1445 |
final CompletableFuture<? extends T> src; |
1446 |
final Function<? super T, ? extends CompletionStage<U>> fn; |
1447 |
final CompletableFuture<U> dst; |
1448 |
final Executor executor; |
1449 |
ThenCompose(CompletableFuture<? extends T> src, |
1450 |
Function<? super T, ? extends CompletionStage<U>> fn, |
1451 |
CompletableFuture<U> dst, |
1452 |
Executor executor) { |
1453 |
this.src = src; this.fn = fn; this.dst = dst; |
1454 |
this.executor = executor; |
1455 |
} |
1456 |
public final CompletableFuture<?> trigger() { |
1457 |
final CompletableFuture<? extends T> a; |
1458 |
final Function<? super T, ? extends CompletionStage<U>> fn; |
1459 |
final CompletableFuture<U> dst; |
1460 |
Object r; T t; Throwable ex; Executor e; |
1461 |
if ((dst = this.dst) != null && |
1462 |
(fn = this.fn) != null && |
1463 |
(a = this.src) != null && |
1464 |
(r = a.result) != null && |
1465 |
compareAndSet(0, 1)) { |
1466 |
if (r instanceof AltResult) { |
1467 |
ex = ((AltResult)r).ex; |
1468 |
t = null; |
1469 |
} |
1470 |
else { |
1471 |
ex = null; |
1472 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1473 |
t = tr; |
1474 |
} |
1475 |
CompletableFuture<U> c = null; |
1476 |
U u = null; |
1477 |
boolean complete = false; |
1478 |
if (ex == null) { |
1479 |
if ((e = executor) != null) |
1480 |
execAsync(e, new AsyncCompose<T,U>(t, fn, dst)); |
1481 |
else { |
1482 |
try { |
1483 |
CompletionStage<U> cs = fn.apply(t); |
1484 |
c = (cs == null) ? null : cs.toCompletableFuture(); |
1485 |
if (c == null) |
1486 |
ex = new NullPointerException(); |
1487 |
} catch (Throwable rex) { |
1488 |
ex = rex; |
1489 |
} |
1490 |
} |
1491 |
} |
1492 |
if (c != null) { |
1493 |
ThenCopy<U> d = null; |
1494 |
Object s; |
1495 |
if ((s = c.result) == null) { |
1496 |
CompletionNode p = new CompletionNode |
1497 |
(d = new ThenCopy<U>(c, dst)); |
1498 |
while ((s = c.result) == null) { |
1499 |
if (UNSAFE.compareAndSwapObject |
1500 |
(c, COMPLETIONS, p.next = c.completions, p)) |
1501 |
break; |
1502 |
} |
1503 |
} |
1504 |
if (s != null && (d == null || d.compareAndSet(0, 1))) { |
1505 |
complete = true; |
1506 |
if (s instanceof AltResult) { |
1507 |
ex = ((AltResult)s).ex; // no rewrap |
1508 |
u = null; |
1509 |
} |
1510 |
else { |
1511 |
@SuppressWarnings("unchecked") U us = (U) s; |
1512 |
u = us; |
1513 |
} |
1514 |
} |
1515 |
} |
1516 |
if (complete || ex != null) |
1517 |
dst.setInternalResult(u, ex); |
1518 |
if (c != null) |
1519 |
c.helpPostComplete(); |
1520 |
} |
1521 |
return dst; |
1522 |
} |
1523 |
private static final long serialVersionUID = 5232453952276885070L; |
1524 |
} |
1525 |
|
1526 |
// Implementations of stage methods with (plain, async, Executor) forms |
1527 |
|
1528 |
private <U> CompletableFuture<U> doThenApply |
1529 |
(Function<? super T,? extends U> fn, |
1530 |
Executor e) { |
1531 |
if (fn == null) throw new NullPointerException(); |
1532 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
1533 |
ThenApply<T,U> d = null; |
1534 |
Object r; |
1535 |
if ((r = result) == null) { |
1536 |
CompletionNode p = new CompletionNode |
1537 |
(d = new ThenApply<T,U>(this, fn, dst, e)); |
1538 |
while ((r = result) == null) { |
1539 |
if (UNSAFE.compareAndSwapObject |
1540 |
(this, COMPLETIONS, p.next = completions, p)) |
1541 |
break; |
1542 |
} |
1543 |
} |
1544 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1545 |
T t; Throwable ex; |
1546 |
if (r instanceof AltResult) { |
1547 |
ex = ((AltResult)r).ex; |
1548 |
t = null; |
1549 |
} |
1550 |
else { |
1551 |
ex = null; |
1552 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1553 |
t = tr; |
1554 |
} |
1555 |
U u = null; |
1556 |
if (ex == null) { |
1557 |
try { |
1558 |
if (e != null) |
1559 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
1560 |
else |
1561 |
u = fn.apply(t); |
1562 |
} catch (Throwable rex) { |
1563 |
ex = rex; |
1564 |
} |
1565 |
} |
1566 |
if (e == null || ex != null) |
1567 |
dst.internalComplete(u, ex); |
1568 |
} |
1569 |
helpPostComplete(); |
1570 |
return dst; |
1571 |
} |
1572 |
|
1573 |
private CompletableFuture<Void> doThenAccept(Consumer<? super T> fn, |
1574 |
Executor e) { |
1575 |
if (fn == null) throw new NullPointerException(); |
1576 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1577 |
ThenAccept<T> d = null; |
1578 |
Object r; |
1579 |
if ((r = result) == null) { |
1580 |
CompletionNode p = new CompletionNode |
1581 |
(d = new ThenAccept<T>(this, fn, dst, e)); |
1582 |
while ((r = result) == null) { |
1583 |
if (UNSAFE.compareAndSwapObject |
1584 |
(this, COMPLETIONS, p.next = completions, p)) |
1585 |
break; |
1586 |
} |
1587 |
} |
1588 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1589 |
T t; Throwable ex; |
1590 |
if (r instanceof AltResult) { |
1591 |
ex = ((AltResult)r).ex; |
1592 |
t = null; |
1593 |
} |
1594 |
else { |
1595 |
ex = null; |
1596 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1597 |
t = tr; |
1598 |
} |
1599 |
if (ex == null) { |
1600 |
try { |
1601 |
if (e != null) |
1602 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
1603 |
else |
1604 |
fn.accept(t); |
1605 |
} catch (Throwable rex) { |
1606 |
ex = rex; |
1607 |
} |
1608 |
} |
1609 |
if (e == null || ex != null) |
1610 |
dst.internalComplete(null, ex); |
1611 |
} |
1612 |
helpPostComplete(); |
1613 |
return dst; |
1614 |
} |
1615 |
|
1616 |
private CompletableFuture<Void> doThenRun(Runnable action, |
1617 |
Executor e) { |
1618 |
if (action == null) throw new NullPointerException(); |
1619 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1620 |
ThenRun d = null; |
1621 |
Object r; |
1622 |
if ((r = result) == null) { |
1623 |
CompletionNode p = new CompletionNode |
1624 |
(d = new ThenRun(this, action, dst, e)); |
1625 |
while ((r = result) == null) { |
1626 |
if (UNSAFE.compareAndSwapObject |
1627 |
(this, COMPLETIONS, p.next = completions, p)) |
1628 |
break; |
1629 |
} |
1630 |
} |
1631 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1632 |
Throwable ex; |
1633 |
if (r instanceof AltResult) |
1634 |
ex = ((AltResult)r).ex; |
1635 |
else |
1636 |
ex = null; |
1637 |
if (ex == null) { |
1638 |
try { |
1639 |
if (e != null) |
1640 |
execAsync(e, new AsyncRun(action, dst)); |
1641 |
else |
1642 |
action.run(); |
1643 |
} catch (Throwable rex) { |
1644 |
ex = rex; |
1645 |
} |
1646 |
} |
1647 |
if (e == null || ex != null) |
1648 |
dst.internalComplete(null, ex); |
1649 |
} |
1650 |
helpPostComplete(); |
1651 |
return dst; |
1652 |
} |
1653 |
|
1654 |
private <U,V> CompletableFuture<V> doThenCombine |
1655 |
(CompletableFuture<? extends U> other, |
1656 |
BiFunction<? super T,? super U,? extends V> fn, |
1657 |
Executor e) { |
1658 |
if (other == null || fn == null) throw new NullPointerException(); |
1659 |
CompletableFuture<V> dst = new CompletableFuture<V>(); |
1660 |
ThenCombine<T,U,V> d = null; |
1661 |
Object r, s = null; |
1662 |
if ((r = result) == null || (s = other.result) == null) { |
1663 |
d = new ThenCombine<T,U,V>(this, other, fn, dst, e); |
1664 |
CompletionNode q = null, p = new CompletionNode(d); |
1665 |
while ((r == null && (r = result) == null) || |
1666 |
(s == null && (s = other.result) == null)) { |
1667 |
if (q != null) { |
1668 |
if (s != null || |
1669 |
UNSAFE.compareAndSwapObject |
1670 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1671 |
break; |
1672 |
} |
1673 |
else if (r != null || |
1674 |
UNSAFE.compareAndSwapObject |
1675 |
(this, COMPLETIONS, p.next = completions, p)) { |
1676 |
if (s != null) |
1677 |
break; |
1678 |
q = new CompletionNode(d); |
1679 |
} |
1680 |
} |
1681 |
} |
1682 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
1683 |
T t; U u; Throwable ex; |
1684 |
if (r instanceof AltResult) { |
1685 |
ex = ((AltResult)r).ex; |
1686 |
t = null; |
1687 |
} |
1688 |
else { |
1689 |
ex = null; |
1690 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1691 |
t = tr; |
1692 |
} |
1693 |
if (ex != null) |
1694 |
u = null; |
1695 |
else if (s instanceof AltResult) { |
1696 |
ex = ((AltResult)s).ex; |
1697 |
u = null; |
1698 |
} |
1699 |
else { |
1700 |
@SuppressWarnings("unchecked") U us = (U) s; |
1701 |
u = us; |
1702 |
} |
1703 |
V v = null; |
1704 |
if (ex == null) { |
1705 |
try { |
1706 |
if (e != null) |
1707 |
execAsync(e, new AsyncCombine<T,U,V>(t, u, fn, dst)); |
1708 |
else |
1709 |
v = fn.apply(t, u); |
1710 |
} catch (Throwable rex) { |
1711 |
ex = rex; |
1712 |
} |
1713 |
} |
1714 |
if (e == null || ex != null) |
1715 |
dst.internalComplete(v, ex); |
1716 |
} |
1717 |
helpPostComplete(); |
1718 |
other.helpPostComplete(); |
1719 |
return dst; |
1720 |
} |
1721 |
|
1722 |
private <U> CompletableFuture<Void> doThenAcceptBoth |
1723 |
(CompletableFuture<? extends U> other, |
1724 |
BiConsumer<? super T,? super U> fn, |
1725 |
Executor e) { |
1726 |
if (other == null || fn == null) throw new NullPointerException(); |
1727 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1728 |
ThenAcceptBoth<T,U> d = null; |
1729 |
Object r, s = null; |
1730 |
if ((r = result) == null || (s = other.result) == null) { |
1731 |
d = new ThenAcceptBoth<T,U>(this, other, fn, dst, e); |
1732 |
CompletionNode q = null, p = new CompletionNode(d); |
1733 |
while ((r == null && (r = result) == null) || |
1734 |
(s == null && (s = other.result) == null)) { |
1735 |
if (q != null) { |
1736 |
if (s != null || |
1737 |
UNSAFE.compareAndSwapObject |
1738 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1739 |
break; |
1740 |
} |
1741 |
else if (r != null || |
1742 |
UNSAFE.compareAndSwapObject |
1743 |
(this, COMPLETIONS, p.next = completions, p)) { |
1744 |
if (s != null) |
1745 |
break; |
1746 |
q = new CompletionNode(d); |
1747 |
} |
1748 |
} |
1749 |
} |
1750 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
1751 |
T t; U u; Throwable ex; |
1752 |
if (r instanceof AltResult) { |
1753 |
ex = ((AltResult)r).ex; |
1754 |
t = null; |
1755 |
} |
1756 |
else { |
1757 |
ex = null; |
1758 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1759 |
t = tr; |
1760 |
} |
1761 |
if (ex != null) |
1762 |
u = null; |
1763 |
else if (s instanceof AltResult) { |
1764 |
ex = ((AltResult)s).ex; |
1765 |
u = null; |
1766 |
} |
1767 |
else { |
1768 |
@SuppressWarnings("unchecked") U us = (U) s; |
1769 |
u = us; |
1770 |
} |
1771 |
if (ex == null) { |
1772 |
try { |
1773 |
if (e != null) |
1774 |
execAsync(e, new AsyncAcceptBoth<T,U>(t, u, fn, dst)); |
1775 |
else |
1776 |
fn.accept(t, u); |
1777 |
} catch (Throwable rex) { |
1778 |
ex = rex; |
1779 |
} |
1780 |
} |
1781 |
if (e == null || ex != null) |
1782 |
dst.internalComplete(null, ex); |
1783 |
} |
1784 |
helpPostComplete(); |
1785 |
other.helpPostComplete(); |
1786 |
return dst; |
1787 |
} |
1788 |
|
1789 |
private CompletableFuture<Void> doRunAfterBoth(CompletableFuture<?> other, |
1790 |
Runnable action, |
1791 |
Executor e) { |
1792 |
if (other == null || action == null) throw new NullPointerException(); |
1793 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1794 |
RunAfterBoth d = null; |
1795 |
Object r, s = null; |
1796 |
if ((r = result) == null || (s = other.result) == null) { |
1797 |
d = new RunAfterBoth(this, other, action, dst, e); |
1798 |
CompletionNode q = null, p = new CompletionNode(d); |
1799 |
while ((r == null && (r = result) == null) || |
1800 |
(s == null && (s = other.result) == null)) { |
1801 |
if (q != null) { |
1802 |
if (s != null || |
1803 |
UNSAFE.compareAndSwapObject |
1804 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1805 |
break; |
1806 |
} |
1807 |
else if (r != null || |
1808 |
UNSAFE.compareAndSwapObject |
1809 |
(this, COMPLETIONS, p.next = completions, p)) { |
1810 |
if (s != null) |
1811 |
break; |
1812 |
q = new CompletionNode(d); |
1813 |
} |
1814 |
} |
1815 |
} |
1816 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
1817 |
Throwable ex; |
1818 |
if (r instanceof AltResult) |
1819 |
ex = ((AltResult)r).ex; |
1820 |
else |
1821 |
ex = null; |
1822 |
if (ex == null && (s instanceof AltResult)) |
1823 |
ex = ((AltResult)s).ex; |
1824 |
if (ex == null) { |
1825 |
try { |
1826 |
if (e != null) |
1827 |
execAsync(e, new AsyncRun(action, dst)); |
1828 |
else |
1829 |
action.run(); |
1830 |
} catch (Throwable rex) { |
1831 |
ex = rex; |
1832 |
} |
1833 |
} |
1834 |
if (e == null || ex != null) |
1835 |
dst.internalComplete(null, ex); |
1836 |
} |
1837 |
helpPostComplete(); |
1838 |
other.helpPostComplete(); |
1839 |
return dst; |
1840 |
} |
1841 |
|
1842 |
private <U> CompletableFuture<U> doApplyToEither |
1843 |
(CompletableFuture<? extends T> other, |
1844 |
Function<? super T, U> fn, |
1845 |
Executor e) { |
1846 |
if (other == null || fn == null) throw new NullPointerException(); |
1847 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
1848 |
ApplyToEither<T,U> d = null; |
1849 |
Object r; |
1850 |
if ((r = result) == null && (r = other.result) == null) { |
1851 |
d = new ApplyToEither<T,U>(this, other, fn, dst, e); |
1852 |
CompletionNode q = null, p = new CompletionNode(d); |
1853 |
while ((r = result) == null && (r = other.result) == null) { |
1854 |
if (q != null) { |
1855 |
if (UNSAFE.compareAndSwapObject |
1856 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1857 |
break; |
1858 |
} |
1859 |
else if (UNSAFE.compareAndSwapObject |
1860 |
(this, COMPLETIONS, p.next = completions, p)) |
1861 |
q = new CompletionNode(d); |
1862 |
} |
1863 |
} |
1864 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1865 |
T t; Throwable ex; |
1866 |
if (r instanceof AltResult) { |
1867 |
ex = ((AltResult)r).ex; |
1868 |
t = null; |
1869 |
} |
1870 |
else { |
1871 |
ex = null; |
1872 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1873 |
t = tr; |
1874 |
} |
1875 |
U u = null; |
1876 |
if (ex == null) { |
1877 |
try { |
1878 |
if (e != null) |
1879 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
1880 |
else |
1881 |
u = fn.apply(t); |
1882 |
} catch (Throwable rex) { |
1883 |
ex = rex; |
1884 |
} |
1885 |
} |
1886 |
if (e == null || ex != null) |
1887 |
dst.internalComplete(u, ex); |
1888 |
} |
1889 |
helpPostComplete(); |
1890 |
other.helpPostComplete(); |
1891 |
return dst; |
1892 |
} |
1893 |
|
1894 |
private CompletableFuture<Void> doAcceptEither |
1895 |
(CompletableFuture<? extends T> other, |
1896 |
Consumer<? super T> fn, |
1897 |
Executor e) { |
1898 |
if (other == null || fn == null) throw new NullPointerException(); |
1899 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1900 |
AcceptEither<T> d = null; |
1901 |
Object r; |
1902 |
if ((r = result) == null && (r = other.result) == null) { |
1903 |
d = new AcceptEither<T>(this, other, fn, dst, e); |
1904 |
CompletionNode q = null, p = new CompletionNode(d); |
1905 |
while ((r = result) == null && (r = other.result) == null) { |
1906 |
if (q != null) { |
1907 |
if (UNSAFE.compareAndSwapObject |
1908 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1909 |
break; |
1910 |
} |
1911 |
else if (UNSAFE.compareAndSwapObject |
1912 |
(this, COMPLETIONS, p.next = completions, p)) |
1913 |
q = new CompletionNode(d); |
1914 |
} |
1915 |
} |
1916 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1917 |
T t; Throwable ex; |
1918 |
if (r instanceof AltResult) { |
1919 |
ex = ((AltResult)r).ex; |
1920 |
t = null; |
1921 |
} |
1922 |
else { |
1923 |
ex = null; |
1924 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1925 |
t = tr; |
1926 |
} |
1927 |
if (ex == null) { |
1928 |
try { |
1929 |
if (e != null) |
1930 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
1931 |
else |
1932 |
fn.accept(t); |
1933 |
} catch (Throwable rex) { |
1934 |
ex = rex; |
1935 |
} |
1936 |
} |
1937 |
if (e == null || ex != null) |
1938 |
dst.internalComplete(null, ex); |
1939 |
} |
1940 |
helpPostComplete(); |
1941 |
other.helpPostComplete(); |
1942 |
return dst; |
1943 |
} |
1944 |
|
1945 |
private CompletableFuture<Void> doRunAfterEither |
1946 |
(CompletableFuture<?> other, |
1947 |
Runnable action, |
1948 |
Executor e) { |
1949 |
if (other == null || action == null) throw new NullPointerException(); |
1950 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1951 |
RunAfterEither d = null; |
1952 |
Object r; |
1953 |
if ((r = result) == null && (r = other.result) == null) { |
1954 |
d = new RunAfterEither(this, other, action, dst, e); |
1955 |
CompletionNode q = null, p = new CompletionNode(d); |
1956 |
while ((r = result) == null && (r = other.result) == null) { |
1957 |
if (q != null) { |
1958 |
if (UNSAFE.compareAndSwapObject |
1959 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1960 |
break; |
1961 |
} |
1962 |
else if (UNSAFE.compareAndSwapObject |
1963 |
(this, COMPLETIONS, p.next = completions, p)) |
1964 |
q = new CompletionNode(d); |
1965 |
} |
1966 |
} |
1967 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1968 |
Throwable ex; |
1969 |
if (r instanceof AltResult) |
1970 |
ex = ((AltResult)r).ex; |
1971 |
else |
1972 |
ex = null; |
1973 |
if (ex == null) { |
1974 |
try { |
1975 |
if (e != null) |
1976 |
execAsync(e, new AsyncRun(action, dst)); |
1977 |
else |
1978 |
action.run(); |
1979 |
} catch (Throwable rex) { |
1980 |
ex = rex; |
1981 |
} |
1982 |
} |
1983 |
if (e == null || ex != null) |
1984 |
dst.internalComplete(null, ex); |
1985 |
} |
1986 |
helpPostComplete(); |
1987 |
other.helpPostComplete(); |
1988 |
return dst; |
1989 |
} |
1990 |
|
1991 |
private <U> CompletableFuture<U> doThenCompose |
1992 |
(Function<? super T, ? extends CompletionStage<U>> fn, |
1993 |
Executor e) { |
1994 |
if (fn == null) throw new NullPointerException(); |
1995 |
CompletableFuture<U> dst = null; |
1996 |
ThenCompose<T,U> d = null; |
1997 |
Object r; |
1998 |
if ((r = result) == null) { |
1999 |
dst = new CompletableFuture<U>(); |
2000 |
CompletionNode p = new CompletionNode |
2001 |
(d = new ThenCompose<T,U>(this, fn, dst, e)); |
2002 |
while ((r = result) == null) { |
2003 |
if (UNSAFE.compareAndSwapObject |
2004 |
(this, COMPLETIONS, p.next = completions, p)) |
2005 |
break; |
2006 |
} |
2007 |
} |
2008 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2009 |
T t; Throwable ex; |
2010 |
if (r instanceof AltResult) { |
2011 |
ex = ((AltResult)r).ex; |
2012 |
t = null; |
2013 |
} |
2014 |
else { |
2015 |
ex = null; |
2016 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2017 |
t = tr; |
2018 |
} |
2019 |
if (ex == null) { |
2020 |
if (e != null) { |
2021 |
if (dst == null) |
2022 |
dst = new CompletableFuture<U>(); |
2023 |
execAsync(e, new AsyncCompose<T,U>(t, fn, dst)); |
2024 |
} |
2025 |
else { |
2026 |
try { |
2027 |
CompletionStage<U> cs = fn.apply(t); |
2028 |
if (cs == null || |
2029 |
(dst = cs.toCompletableFuture()) == null) |
2030 |
ex = new NullPointerException(); |
2031 |
} catch (Throwable rex) { |
2032 |
ex = rex; |
2033 |
} |
2034 |
} |
2035 |
} |
2036 |
if (dst == null) |
2037 |
dst = new CompletableFuture<U>(); |
2038 |
if (ex != null) |
2039 |
dst.internalComplete(null, ex); |
2040 |
} |
2041 |
helpPostComplete(); |
2042 |
dst.helpPostComplete(); |
2043 |
return dst; |
2044 |
} |
2045 |
|
2046 |
private CompletableFuture<T> doWhenComplete |
2047 |
(BiConsumer<? super T, ? super Throwable> fn, |
2048 |
Executor e) { |
2049 |
if (fn == null) throw new NullPointerException(); |
2050 |
CompletableFuture<T> dst = new CompletableFuture<T>(); |
2051 |
WhenCompleteCompletion<T> d = null; |
2052 |
Object r; |
2053 |
if ((r = result) == null) { |
2054 |
CompletionNode p = |
2055 |
new CompletionNode(d = new WhenCompleteCompletion<T> |
2056 |
(this, fn, dst, e)); |
2057 |
while ((r = result) == null) { |
2058 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2059 |
p.next = completions, p)) |
2060 |
break; |
2061 |
} |
2062 |
} |
2063 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2064 |
T t; Throwable ex; |
2065 |
if (r instanceof AltResult) { |
2066 |
ex = ((AltResult)r).ex; |
2067 |
t = null; |
2068 |
} |
2069 |
else { |
2070 |
ex = null; |
2071 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2072 |
t = tr; |
2073 |
} |
2074 |
Throwable dx = null; |
2075 |
try { |
2076 |
if (e != null) |
2077 |
execAsync(e, new AsyncWhenComplete<T>(t, ex, fn, dst)); |
2078 |
else |
2079 |
fn.accept(t, ex); |
2080 |
} catch (Throwable rex) { |
2081 |
dx = rex; |
2082 |
} |
2083 |
if (e == null || dx != null) |
2084 |
dst.internalComplete(t, ex != null ? ex : dx); |
2085 |
} |
2086 |
helpPostComplete(); |
2087 |
return dst; |
2088 |
} |
2089 |
|
2090 |
private <U> CompletableFuture<U> doHandle |
2091 |
(BiFunction<? super T, Throwable, ? extends U> fn, |
2092 |
Executor e) { |
2093 |
if (fn == null) throw new NullPointerException(); |
2094 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
2095 |
HandleCompletion<T,U> d = null; |
2096 |
Object r; |
2097 |
if ((r = result) == null) { |
2098 |
CompletionNode p = |
2099 |
new CompletionNode(d = new HandleCompletion<T,U> |
2100 |
(this, fn, dst, e)); |
2101 |
while ((r = result) == null) { |
2102 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2103 |
p.next = completions, p)) |
2104 |
break; |
2105 |
} |
2106 |
} |
2107 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2108 |
T t; Throwable ex; |
2109 |
if (r instanceof AltResult) { |
2110 |
ex = ((AltResult)r).ex; |
2111 |
t = null; |
2112 |
} |
2113 |
else { |
2114 |
ex = null; |
2115 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2116 |
t = tr; |
2117 |
} |
2118 |
U u = null; |
2119 |
Throwable dx = null; |
2120 |
try { |
2121 |
if (e != null) |
2122 |
execAsync(e, new AsyncCombine<T,Throwable,U>(t, ex, fn, dst)); |
2123 |
else { |
2124 |
u = fn.apply(t, ex); |
2125 |
dx = null; |
2126 |
} |
2127 |
} catch (Throwable rex) { |
2128 |
dx = rex; |
2129 |
u = null; |
2130 |
} |
2131 |
if (e == null || dx != null) |
2132 |
dst.internalComplete(u, dx); |
2133 |
} |
2134 |
helpPostComplete(); |
2135 |
return dst; |
2136 |
} |
2137 |
|
2138 |
|
2139 |
// public methods |
2140 |
|
2141 |
/** |
2142 |
* Creates a new incomplete CompletableFuture. |
2143 |
*/ |
2144 |
public CompletableFuture() { |
2145 |
} |
2146 |
|
2147 |
/** |
2148 |
* Returns a new CompletableFuture that is asynchronously completed |
2149 |
* by a task running in the {@link ForkJoinPool#commonPool()} with |
2150 |
* the value obtained by calling the given Supplier. |
2151 |
* |
2152 |
* @param supplier a function returning the value to be used |
2153 |
* to complete the returned CompletableFuture |
2154 |
* @param <U> the function's return type |
2155 |
* @return the new CompletableFuture |
2156 |
*/ |
2157 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier) { |
2158 |
if (supplier == null) throw new NullPointerException(); |
2159 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
2160 |
execAsync(ForkJoinPool.commonPool(), new AsyncSupply<U>(supplier, f)); |
2161 |
return f; |
2162 |
} |
2163 |
|
2164 |
/** |
2165 |
* Returns a new CompletableFuture that is asynchronously completed |
2166 |
* by a task running in the given executor with the value obtained |
2167 |
* by calling the given Supplier. |
2168 |
* |
2169 |
* @param supplier a function returning the value to be used |
2170 |
* to complete the returned CompletableFuture |
2171 |
* @param executor the executor to use for asynchronous execution |
2172 |
* @param <U> the function's return type |
2173 |
* @return the new CompletableFuture |
2174 |
*/ |
2175 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier, |
2176 |
Executor executor) { |
2177 |
if (executor == null || supplier == null) |
2178 |
throw new NullPointerException(); |
2179 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
2180 |
execAsync(executor, new AsyncSupply<U>(supplier, f)); |
2181 |
return f; |
2182 |
} |
2183 |
|
2184 |
/** |
2185 |
* Returns a new CompletableFuture that is asynchronously completed |
2186 |
* by a task running in the {@link ForkJoinPool#commonPool()} after |
2187 |
* it runs the given action. |
2188 |
* |
2189 |
* @param runnable the action to run before completing the |
2190 |
* returned CompletableFuture |
2191 |
* @return the new CompletableFuture |
2192 |
*/ |
2193 |
public static CompletableFuture<Void> runAsync(Runnable runnable) { |
2194 |
if (runnable == null) throw new NullPointerException(); |
2195 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
2196 |
execAsync(ForkJoinPool.commonPool(), new AsyncRun(runnable, f)); |
2197 |
return f; |
2198 |
} |
2199 |
|
2200 |
/** |
2201 |
* Returns a new CompletableFuture that is asynchronously completed |
2202 |
* by a task running in the given executor after it runs the given |
2203 |
* action. |
2204 |
* |
2205 |
* @param runnable the action to run before completing the |
2206 |
* returned CompletableFuture |
2207 |
* @param executor the executor to use for asynchronous execution |
2208 |
* @return the new CompletableFuture |
2209 |
*/ |
2210 |
public static CompletableFuture<Void> runAsync(Runnable runnable, |
2211 |
Executor executor) { |
2212 |
if (executor == null || runnable == null) |
2213 |
throw new NullPointerException(); |
2214 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
2215 |
execAsync(executor, new AsyncRun(runnable, f)); |
2216 |
return f; |
2217 |
} |
2218 |
|
2219 |
/** |
2220 |
* Returns a new CompletableFuture that is already completed with |
2221 |
* the given value. |
2222 |
* |
2223 |
* @param value the value |
2224 |
* @param <U> the type of the value |
2225 |
* @return the completed CompletableFuture |
2226 |
*/ |
2227 |
public static <U> CompletableFuture<U> completedFuture(U value) { |
2228 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
2229 |
f.result = (value == null) ? NIL : value; |
2230 |
return f; |
2231 |
} |
2232 |
|
2233 |
/** |
2234 |
* Returns {@code true} if completed in any fashion: normally, |
2235 |
* exceptionally, or via cancellation. |
2236 |
* |
2237 |
* @return {@code true} if completed |
2238 |
*/ |
2239 |
public boolean isDone() { |
2240 |
return result != null; |
2241 |
} |
2242 |
|
2243 |
/** |
2244 |
* Waits if necessary for this future to complete, and then |
2245 |
* returns its result. |
2246 |
* |
2247 |
* @return the result value |
2248 |
* @throws CancellationException if this future was cancelled |
2249 |
* @throws ExecutionException if this future completed exceptionally |
2250 |
* @throws InterruptedException if the current thread was interrupted |
2251 |
* while waiting |
2252 |
*/ |
2253 |
public T get() throws InterruptedException, ExecutionException { |
2254 |
Object r; Throwable ex, cause; |
2255 |
if ((r = result) == null && (r = waitingGet(true)) == null) |
2256 |
throw new InterruptedException(); |
2257 |
if (!(r instanceof AltResult)) { |
2258 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2259 |
return tr; |
2260 |
} |
2261 |
if ((ex = ((AltResult)r).ex) == null) |
2262 |
return null; |
2263 |
if (ex instanceof CancellationException) |
2264 |
throw (CancellationException)ex; |
2265 |
if ((ex instanceof CompletionException) && |
2266 |
(cause = ex.getCause()) != null) |
2267 |
ex = cause; |
2268 |
throw new ExecutionException(ex); |
2269 |
} |
2270 |
|
2271 |
/** |
2272 |
* Waits if necessary for at most the given time for this future |
2273 |
* to complete, and then returns its result, if available. |
2274 |
* |
2275 |
* @param timeout the maximum time to wait |
2276 |
* @param unit the time unit of the timeout argument |
2277 |
* @return the result value |
2278 |
* @throws CancellationException if this future was cancelled |
2279 |
* @throws ExecutionException if this future completed exceptionally |
2280 |
* @throws InterruptedException if the current thread was interrupted |
2281 |
* while waiting |
2282 |
* @throws TimeoutException if the wait timed out |
2283 |
*/ |
2284 |
public T get(long timeout, TimeUnit unit) |
2285 |
throws InterruptedException, ExecutionException, TimeoutException { |
2286 |
Object r; Throwable ex, cause; |
2287 |
long nanos = unit.toNanos(timeout); |
2288 |
if (Thread.interrupted()) |
2289 |
throw new InterruptedException(); |
2290 |
if ((r = result) == null) |
2291 |
r = timedAwaitDone(nanos); |
2292 |
if (!(r instanceof AltResult)) { |
2293 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2294 |
return tr; |
2295 |
} |
2296 |
if ((ex = ((AltResult)r).ex) == null) |
2297 |
return null; |
2298 |
if (ex instanceof CancellationException) |
2299 |
throw (CancellationException)ex; |
2300 |
if ((ex instanceof CompletionException) && |
2301 |
(cause = ex.getCause()) != null) |
2302 |
ex = cause; |
2303 |
throw new ExecutionException(ex); |
2304 |
} |
2305 |
|
2306 |
/** |
2307 |
* Returns the result value when complete, or throws an |
2308 |
* (unchecked) exception if completed exceptionally. To better |
2309 |
* conform with the use of common functional forms, if a |
2310 |
* computation involved in the completion of this |
2311 |
* CompletableFuture threw an exception, this method throws an |
2312 |
* (unchecked) {@link CompletionException} with the underlying |
2313 |
* exception as its cause. |
2314 |
* |
2315 |
* @return the result value |
2316 |
* @throws CancellationException if the computation was cancelled |
2317 |
* @throws CompletionException if this future completed |
2318 |
* exceptionally or a completion computation threw an exception |
2319 |
*/ |
2320 |
public T join() { |
2321 |
Object r; Throwable ex; |
2322 |
if ((r = result) == null) |
2323 |
r = waitingGet(false); |
2324 |
if (!(r instanceof AltResult)) { |
2325 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2326 |
return tr; |
2327 |
} |
2328 |
if ((ex = ((AltResult)r).ex) == null) |
2329 |
return null; |
2330 |
if (ex instanceof CancellationException) |
2331 |
throw (CancellationException)ex; |
2332 |
if (ex instanceof CompletionException) |
2333 |
throw (CompletionException)ex; |
2334 |
throw new CompletionException(ex); |
2335 |
} |
2336 |
|
2337 |
/** |
2338 |
* Returns the result value (or throws any encountered exception) |
2339 |
* if completed, else returns the given valueIfAbsent. |
2340 |
* |
2341 |
* @param valueIfAbsent the value to return if not completed |
2342 |
* @return the result value, if completed, else the given valueIfAbsent |
2343 |
* @throws CancellationException if the computation was cancelled |
2344 |
* @throws CompletionException if this future completed |
2345 |
* exceptionally or a completion computation threw an exception |
2346 |
*/ |
2347 |
public T getNow(T valueIfAbsent) { |
2348 |
Object r; Throwable ex; |
2349 |
if ((r = result) == null) |
2350 |
return valueIfAbsent; |
2351 |
if (!(r instanceof AltResult)) { |
2352 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2353 |
return tr; |
2354 |
} |
2355 |
if ((ex = ((AltResult)r).ex) == null) |
2356 |
return null; |
2357 |
if (ex instanceof CancellationException) |
2358 |
throw (CancellationException)ex; |
2359 |
if (ex instanceof CompletionException) |
2360 |
throw (CompletionException)ex; |
2361 |
throw new CompletionException(ex); |
2362 |
} |
2363 |
|
2364 |
/** |
2365 |
* If not already completed, sets the value returned by {@link |
2366 |
* #get()} and related methods to the given value. |
2367 |
* |
2368 |
* @param value the result value |
2369 |
* @return {@code true} if this invocation caused this CompletableFuture |
2370 |
* to transition to a completed state, else {@code false} |
2371 |
*/ |
2372 |
public boolean complete(T value) { |
2373 |
boolean triggered = result == null && |
2374 |
UNSAFE.compareAndSwapObject(this, RESULT, null, |
2375 |
value == null ? NIL : value); |
2376 |
postComplete(); |
2377 |
return triggered; |
2378 |
} |
2379 |
|
2380 |
/** |
2381 |
* If not already completed, causes invocations of {@link #get()} |
2382 |
* and related methods to throw the given exception. |
2383 |
* |
2384 |
* @param ex the exception |
2385 |
* @return {@code true} if this invocation caused this CompletableFuture |
2386 |
* to transition to a completed state, else {@code false} |
2387 |
*/ |
2388 |
public boolean completeExceptionally(Throwable ex) { |
2389 |
if (ex == null) throw new NullPointerException(); |
2390 |
boolean triggered = result == null && |
2391 |
UNSAFE.compareAndSwapObject(this, RESULT, null, new AltResult(ex)); |
2392 |
postComplete(); |
2393 |
return triggered; |
2394 |
} |
2395 |
|
2396 |
// CompletionStage methods |
2397 |
|
2398 |
public <U> CompletableFuture<U> thenApply |
2399 |
(Function<? super T,? extends U> fn) { |
2400 |
return doThenApply(fn, null); |
2401 |
} |
2402 |
|
2403 |
public <U> CompletableFuture<U> thenApplyAsync |
2404 |
(Function<? super T,? extends U> fn) { |
2405 |
return doThenApply(fn, ForkJoinPool.commonPool()); |
2406 |
} |
2407 |
|
2408 |
public <U> CompletableFuture<U> thenApplyAsync |
2409 |
(Function<? super T,? extends U> fn, |
2410 |
Executor executor) { |
2411 |
if (executor == null) throw new NullPointerException(); |
2412 |
return doThenApply(fn, executor); |
2413 |
} |
2414 |
|
2415 |
public CompletableFuture<Void> thenAccept |
2416 |
(Consumer<? super T> action) { |
2417 |
return doThenAccept(action, null); |
2418 |
} |
2419 |
|
2420 |
public CompletableFuture<Void> thenAcceptAsync |
2421 |
(Consumer<? super T> action) { |
2422 |
return doThenAccept(action, ForkJoinPool.commonPool()); |
2423 |
} |
2424 |
|
2425 |
public CompletableFuture<Void> thenAcceptAsync |
2426 |
(Consumer<? super T> action, |
2427 |
Executor executor) { |
2428 |
if (executor == null) throw new NullPointerException(); |
2429 |
return doThenAccept(action, executor); |
2430 |
} |
2431 |
|
2432 |
public CompletableFuture<Void> thenRun |
2433 |
(Runnable action) { |
2434 |
return doThenRun(action, null); |
2435 |
} |
2436 |
|
2437 |
public CompletableFuture<Void> thenRunAsync |
2438 |
(Runnable action) { |
2439 |
return doThenRun(action, ForkJoinPool.commonPool()); |
2440 |
} |
2441 |
|
2442 |
public CompletableFuture<Void> thenRunAsync |
2443 |
(Runnable action, |
2444 |
Executor executor) { |
2445 |
if (executor == null) throw new NullPointerException(); |
2446 |
return doThenRun(action, executor); |
2447 |
} |
2448 |
|
2449 |
public <U,V> CompletableFuture<V> thenCombine |
2450 |
(CompletionStage<? extends U> other, |
2451 |
BiFunction<? super T,? super U,? extends V> fn) { |
2452 |
return doThenCombine(other.toCompletableFuture(), fn, null); |
2453 |
} |
2454 |
|
2455 |
public <U,V> CompletableFuture<V> thenCombineAsync |
2456 |
(CompletionStage<? extends U> other, |
2457 |
BiFunction<? super T,? super U,? extends V> fn) { |
2458 |
return doThenCombine(other.toCompletableFuture(), fn, |
2459 |
ForkJoinPool.commonPool()); |
2460 |
} |
2461 |
|
2462 |
public <U,V> CompletableFuture<V> thenCombineAsync |
2463 |
(CompletionStage<? extends U> other, |
2464 |
BiFunction<? super T,? super U,? extends V> fn, |
2465 |
Executor executor) { |
2466 |
if (executor == null) throw new NullPointerException(); |
2467 |
return doThenCombine(other.toCompletableFuture(), fn, executor); |
2468 |
} |
2469 |
|
2470 |
public <U> CompletableFuture<Void> thenAcceptBoth |
2471 |
(CompletionStage<? extends U> other, |
2472 |
BiConsumer<? super T, ? super U> action) { |
2473 |
return doThenAcceptBoth(other.toCompletableFuture(), action, null); |
2474 |
} |
2475 |
|
2476 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2477 |
(CompletionStage<? extends U> other, |
2478 |
BiConsumer<? super T, ? super U> action) { |
2479 |
return doThenAcceptBoth(other.toCompletableFuture(), action, |
2480 |
ForkJoinPool.commonPool()); |
2481 |
} |
2482 |
|
2483 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2484 |
(CompletionStage<? extends U> other, |
2485 |
BiConsumer<? super T, ? super U> action, |
2486 |
Executor executor) { |
2487 |
if (executor == null) throw new NullPointerException(); |
2488 |
return doThenAcceptBoth(other.toCompletableFuture(), action, executor); |
2489 |
} |
2490 |
|
2491 |
public CompletableFuture<Void> runAfterBoth |
2492 |
(CompletionStage<?> other, |
2493 |
Runnable action) { |
2494 |
return doRunAfterBoth(other.toCompletableFuture(), action, null); |
2495 |
} |
2496 |
|
2497 |
public CompletableFuture<Void> runAfterBothAsync |
2498 |
(CompletionStage<?> other, |
2499 |
Runnable action) { |
2500 |
return doRunAfterBoth(other.toCompletableFuture(), action, |
2501 |
ForkJoinPool.commonPool()); |
2502 |
} |
2503 |
|
2504 |
public CompletableFuture<Void> runAfterBothAsync |
2505 |
(CompletionStage<?> other, |
2506 |
Runnable action, |
2507 |
Executor executor) { |
2508 |
if (executor == null) throw new NullPointerException(); |
2509 |
return doRunAfterBoth(other.toCompletableFuture(), action, executor); |
2510 |
} |
2511 |
|
2512 |
|
2513 |
public <U> CompletableFuture<U> applyToEither |
2514 |
(CompletionStage<? extends T> other, |
2515 |
Function<? super T, U> fn) { |
2516 |
return doApplyToEither(other.toCompletableFuture(), fn, null); |
2517 |
} |
2518 |
|
2519 |
public <U> CompletableFuture<U> applyToEitherAsync |
2520 |
(CompletionStage<? extends T> other, |
2521 |
Function<? super T, U> fn) { |
2522 |
return doApplyToEither(other.toCompletableFuture(), fn, |
2523 |
ForkJoinPool.commonPool()); |
2524 |
} |
2525 |
|
2526 |
public <U> CompletableFuture<U> applyToEitherAsync |
2527 |
(CompletionStage<? extends T> other, |
2528 |
Function<? super T, U> fn, |
2529 |
Executor executor) { |
2530 |
if (executor == null) throw new NullPointerException(); |
2531 |
return doApplyToEither(other.toCompletableFuture(), fn, executor); |
2532 |
} |
2533 |
|
2534 |
public CompletableFuture<Void> acceptEither |
2535 |
(CompletionStage<? extends T> other, |
2536 |
Consumer<? super T> action) { |
2537 |
return doAcceptEither(other.toCompletableFuture(), action, null); |
2538 |
} |
2539 |
|
2540 |
public CompletableFuture<Void> acceptEitherAsync |
2541 |
(CompletionStage<? extends T> other, |
2542 |
Consumer<? super T> action) { |
2543 |
return doAcceptEither(other.toCompletableFuture(), action, |
2544 |
ForkJoinPool.commonPool()); |
2545 |
} |
2546 |
|
2547 |
public CompletableFuture<Void> acceptEitherAsync |
2548 |
(CompletionStage<? extends T> other, |
2549 |
Consumer<? super T> action, |
2550 |
Executor executor) { |
2551 |
if (executor == null) throw new NullPointerException(); |
2552 |
return doAcceptEither(other.toCompletableFuture(), action, executor); |
2553 |
} |
2554 |
|
2555 |
public CompletableFuture<Void> runAfterEither(CompletionStage<?> other, |
2556 |
Runnable action) { |
2557 |
return doRunAfterEither(other.toCompletableFuture(), action, null); |
2558 |
} |
2559 |
|
2560 |
public CompletableFuture<Void> runAfterEitherAsync |
2561 |
(CompletionStage<?> other, |
2562 |
Runnable action) { |
2563 |
return doRunAfterEither(other.toCompletableFuture(), action, |
2564 |
ForkJoinPool.commonPool()); |
2565 |
} |
2566 |
|
2567 |
public CompletableFuture<Void> runAfterEitherAsync |
2568 |
(CompletionStage<?> other, |
2569 |
Runnable action, |
2570 |
Executor executor) { |
2571 |
if (executor == null) throw new NullPointerException(); |
2572 |
return doRunAfterEither(other.toCompletableFuture(), action, executor); |
2573 |
} |
2574 |
|
2575 |
public <U> CompletableFuture<U> thenCompose |
2576 |
(Function<? super T, ? extends CompletionStage<U>> fn) { |
2577 |
return doThenCompose(fn, null); |
2578 |
} |
2579 |
|
2580 |
public <U> CompletableFuture<U> thenComposeAsync |
2581 |
(Function<? super T, ? extends CompletionStage<U>> fn) { |
2582 |
return doThenCompose(fn, ForkJoinPool.commonPool()); |
2583 |
} |
2584 |
|
2585 |
public <U> CompletableFuture<U> thenComposeAsync |
2586 |
(Function<? super T, ? extends CompletionStage<U>> fn, |
2587 |
Executor executor) { |
2588 |
if (executor == null) throw new NullPointerException(); |
2589 |
return doThenCompose(fn, executor); |
2590 |
} |
2591 |
|
2592 |
public CompletableFuture<T> whenComplete |
2593 |
(BiConsumer<? super T, ? super Throwable> action) { |
2594 |
return doWhenComplete(action, null); |
2595 |
} |
2596 |
|
2597 |
public CompletableFuture<T> whenCompleteAsync |
2598 |
(BiConsumer<? super T, ? super Throwable> action) { |
2599 |
return doWhenComplete(action, ForkJoinPool.commonPool()); |
2600 |
} |
2601 |
|
2602 |
public CompletableFuture<T> whenCompleteAsync |
2603 |
(BiConsumer<? super T, ? super Throwable> action, |
2604 |
Executor executor) { |
2605 |
if (executor == null) throw new NullPointerException(); |
2606 |
return doWhenComplete(action, executor); |
2607 |
} |
2608 |
|
2609 |
public <U> CompletableFuture<U> handle |
2610 |
(BiFunction<? super T, Throwable, ? extends U> fn) { |
2611 |
return doHandle(fn, null); |
2612 |
} |
2613 |
|
2614 |
public <U> CompletableFuture<U> handleAsync |
2615 |
(BiFunction<? super T, Throwable, ? extends U> fn) { |
2616 |
return doHandle(fn, ForkJoinPool.commonPool()); |
2617 |
} |
2618 |
|
2619 |
public <U> CompletableFuture<U> handleAsync |
2620 |
(BiFunction<? super T, Throwable, ? extends U> fn, |
2621 |
Executor executor) { |
2622 |
if (executor == null) throw new NullPointerException(); |
2623 |
return doHandle(fn, executor); |
2624 |
} |
2625 |
|
2626 |
/** |
2627 |
* Returns this CompletableFuture |
2628 |
* |
2629 |
* @return this CompletableFuture |
2630 |
*/ |
2631 |
public CompletableFuture<T> toCompletableFuture() { |
2632 |
return this; |
2633 |
} |
2634 |
|
2635 |
// not in interface CompletionStage |
2636 |
|
2637 |
/** |
2638 |
* Returns a new CompletableFuture that is completed when this |
2639 |
* CompletableFuture completes, with the result of the given |
2640 |
* function of the exception triggering this CompletableFuture's |
2641 |
* completion when it completes exceptionally; otherwise, if this |
2642 |
* CompletableFuture completes normally, then the returned |
2643 |
* CompletableFuture also completes normally with the same value. |
2644 |
* Note: More flexible versions of this functionality are |
2645 |
* available using methods {@code whenComplete} and {@code handle}. |
2646 |
* |
2647 |
* @param fn the function to use to compute the value of the |
2648 |
* returned CompletableFuture if this CompletableFuture completed |
2649 |
* exceptionally |
2650 |
* @return the new CompletableFuture |
2651 |
*/ |
2652 |
public CompletableFuture<T> exceptionally |
2653 |
(Function<Throwable, ? extends T> fn) { |
2654 |
if (fn == null) throw new NullPointerException(); |
2655 |
CompletableFuture<T> dst = new CompletableFuture<T>(); |
2656 |
ExceptionCompletion<T> d = null; |
2657 |
Object r; |
2658 |
if ((r = result) == null) { |
2659 |
CompletionNode p = |
2660 |
new CompletionNode(d = new ExceptionCompletion<T> |
2661 |
(this, fn, dst)); |
2662 |
while ((r = result) == null) { |
2663 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2664 |
p.next = completions, p)) |
2665 |
break; |
2666 |
} |
2667 |
} |
2668 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2669 |
T t = null; Throwable ex, dx = null; |
2670 |
if (r instanceof AltResult) { |
2671 |
if ((ex = ((AltResult)r).ex) != null) { |
2672 |
try { |
2673 |
t = fn.apply(ex); |
2674 |
} catch (Throwable rex) { |
2675 |
dx = rex; |
2676 |
} |
2677 |
} |
2678 |
} |
2679 |
else { |
2680 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2681 |
t = tr; |
2682 |
} |
2683 |
dst.internalComplete(t, dx); |
2684 |
} |
2685 |
helpPostComplete(); |
2686 |
return dst; |
2687 |
} |
2688 |
|
2689 |
/* ------------- Arbitrary-arity constructions -------------- */ |
2690 |
|
2691 |
/* |
2692 |
* The basic plan of attack is to recursively form binary |
2693 |
* completion trees of elements. This can be overkill for small |
2694 |
* sets, but scales nicely. The And/All vs Or/Any forms use the |
2695 |
* same idea, but details differ. |
2696 |
*/ |
2697 |
|
2698 |
/** |
2699 |
* Returns a new CompletableFuture that is completed when all of |
2700 |
* the given CompletableFutures complete. If any of the given |
2701 |
* CompletableFutures complete exceptionally, then the returned |
2702 |
* CompletableFuture also does so, with a CompletionException |
2703 |
* holding this exception as its cause. Otherwise, the results, |
2704 |
* if any, of the given CompletableFutures are not reflected in |
2705 |
* the returned CompletableFuture, but may be obtained by |
2706 |
* inspecting them individually. If no CompletableFutures are |
2707 |
* provided, returns a CompletableFuture completed with the value |
2708 |
* {@code null}. |
2709 |
* |
2710 |
* <p>Among the applications of this method is to await completion |
2711 |
* of a set of independent CompletableFutures before continuing a |
2712 |
* program, as in: {@code CompletableFuture.allOf(c1, c2, |
2713 |
* c3).join();}. |
2714 |
* |
2715 |
* @param cfs the CompletableFutures |
2716 |
* @return a new CompletableFuture that is completed when all of the |
2717 |
* given CompletableFutures complete |
2718 |
* @throws NullPointerException if the array or any of its elements are |
2719 |
* {@code null} |
2720 |
*/ |
2721 |
public static CompletableFuture<Void> allOf(CompletableFuture<?>... cfs) { |
2722 |
int len = cfs.length; // Directly handle empty and singleton cases |
2723 |
if (len > 1) |
2724 |
return allTree(cfs, 0, len - 1); |
2725 |
else { |
2726 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2727 |
CompletableFuture<?> f; |
2728 |
if (len == 0) |
2729 |
dst.result = NIL; |
2730 |
else if ((f = cfs[0]) == null) |
2731 |
throw new NullPointerException(); |
2732 |
else { |
2733 |
ThenPropagate d = null; |
2734 |
CompletionNode p = null; |
2735 |
Object r; |
2736 |
while ((r = f.result) == null) { |
2737 |
if (d == null) |
2738 |
d = new ThenPropagate(f, dst); |
2739 |
else if (p == null) |
2740 |
p = new CompletionNode(d); |
2741 |
else if (UNSAFE.compareAndSwapObject |
2742 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2743 |
break; |
2744 |
} |
2745 |
if (r != null && (d == null || d.compareAndSet(0, 1))) |
2746 |
dst.internalComplete(null, (r instanceof AltResult) ? |
2747 |
((AltResult)r).ex : null); |
2748 |
f.helpPostComplete(); |
2749 |
} |
2750 |
return dst; |
2751 |
} |
2752 |
} |
2753 |
|
2754 |
/** |
2755 |
* Recursively constructs an And'ed tree of CompletableFutures. |
2756 |
* Called only when array known to have at least two elements. |
2757 |
*/ |
2758 |
private static CompletableFuture<Void> allTree(CompletableFuture<?>[] cfs, |
2759 |
int lo, int hi) { |
2760 |
CompletableFuture<?> fst, snd; |
2761 |
int mid = (lo + hi) >>> 1; |
2762 |
if ((fst = (lo == mid ? cfs[lo] : allTree(cfs, lo, mid))) == null || |
2763 |
(snd = (hi == mid+1 ? cfs[hi] : allTree(cfs, mid+1, hi))) == null) |
2764 |
throw new NullPointerException(); |
2765 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2766 |
AndCompletion d = null; |
2767 |
CompletionNode p = null, q = null; |
2768 |
Object r = null, s = null; |
2769 |
while ((r = fst.result) == null || (s = snd.result) == null) { |
2770 |
if (d == null) |
2771 |
d = new AndCompletion(fst, snd, dst); |
2772 |
else if (p == null) |
2773 |
p = new CompletionNode(d); |
2774 |
else if (q == null) { |
2775 |
if (UNSAFE.compareAndSwapObject |
2776 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
2777 |
q = new CompletionNode(d); |
2778 |
} |
2779 |
else if (UNSAFE.compareAndSwapObject |
2780 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
2781 |
break; |
2782 |
} |
2783 |
if ((r != null || (r = fst.result) != null) && |
2784 |
(s != null || (s = snd.result) != null) && |
2785 |
(d == null || d.compareAndSet(0, 1))) { |
2786 |
Throwable ex; |
2787 |
if (r instanceof AltResult) |
2788 |
ex = ((AltResult)r).ex; |
2789 |
else |
2790 |
ex = null; |
2791 |
if (ex == null && (s instanceof AltResult)) |
2792 |
ex = ((AltResult)s).ex; |
2793 |
dst.internalComplete(null, ex); |
2794 |
} |
2795 |
fst.helpPostComplete(); |
2796 |
snd.helpPostComplete(); |
2797 |
return dst; |
2798 |
} |
2799 |
|
2800 |
/** |
2801 |
* Returns a new CompletableFuture that is completed when any of |
2802 |
* the given CompletableFutures complete, with the same result. |
2803 |
* Otherwise, if it completed exceptionally, the returned |
2804 |
* CompletableFuture also does so, with a CompletionException |
2805 |
* holding this exception as its cause. If no CompletableFutures |
2806 |
* are provided, returns an incomplete CompletableFuture. |
2807 |
* |
2808 |
* @param cfs the CompletableFutures |
2809 |
* @return a new CompletableFuture that is completed with the |
2810 |
* result or exception of any of the given CompletableFutures when |
2811 |
* one completes |
2812 |
* @throws NullPointerException if the array or any of its elements are |
2813 |
* {@code null} |
2814 |
*/ |
2815 |
public static CompletableFuture<Object> anyOf(CompletableFuture<?>... cfs) { |
2816 |
int len = cfs.length; // Same idea as allOf |
2817 |
if (len > 1) |
2818 |
return anyTree(cfs, 0, len - 1); |
2819 |
else { |
2820 |
CompletableFuture<Object> dst = new CompletableFuture<Object>(); |
2821 |
CompletableFuture<?> f; |
2822 |
if (len == 0) |
2823 |
; // skip |
2824 |
else if ((f = cfs[0]) == null) |
2825 |
throw new NullPointerException(); |
2826 |
else { |
2827 |
ThenCopy<Object> d = null; |
2828 |
CompletionNode p = null; |
2829 |
Object r; |
2830 |
while ((r = f.result) == null) { |
2831 |
if (d == null) |
2832 |
d = new ThenCopy<Object>(f, dst); |
2833 |
else if (p == null) |
2834 |
p = new CompletionNode(d); |
2835 |
else if (UNSAFE.compareAndSwapObject |
2836 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2837 |
break; |
2838 |
} |
2839 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2840 |
Throwable ex; Object t; |
2841 |
if (r instanceof AltResult) { |
2842 |
ex = ((AltResult)r).ex; |
2843 |
t = null; |
2844 |
} |
2845 |
else { |
2846 |
ex = null; |
2847 |
t = r; |
2848 |
} |
2849 |
dst.internalComplete(t, ex); |
2850 |
} |
2851 |
f.helpPostComplete(); |
2852 |
} |
2853 |
return dst; |
2854 |
} |
2855 |
} |
2856 |
|
2857 |
/** |
2858 |
* Recursively constructs an Or'ed tree of CompletableFutures. |
2859 |
*/ |
2860 |
private static CompletableFuture<Object> anyTree(CompletableFuture<?>[] cfs, |
2861 |
int lo, int hi) { |
2862 |
CompletableFuture<?> fst, snd; |
2863 |
int mid = (lo + hi) >>> 1; |
2864 |
if ((fst = (lo == mid ? cfs[lo] : anyTree(cfs, lo, mid))) == null || |
2865 |
(snd = (hi == mid+1 ? cfs[hi] : anyTree(cfs, mid+1, hi))) == null) |
2866 |
throw new NullPointerException(); |
2867 |
CompletableFuture<Object> dst = new CompletableFuture<Object>(); |
2868 |
OrCompletion d = null; |
2869 |
CompletionNode p = null, q = null; |
2870 |
Object r; |
2871 |
while ((r = fst.result) == null && (r = snd.result) == null) { |
2872 |
if (d == null) |
2873 |
d = new OrCompletion(fst, snd, dst); |
2874 |
else if (p == null) |
2875 |
p = new CompletionNode(d); |
2876 |
else if (q == null) { |
2877 |
if (UNSAFE.compareAndSwapObject |
2878 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
2879 |
q = new CompletionNode(d); |
2880 |
} |
2881 |
else if (UNSAFE.compareAndSwapObject |
2882 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
2883 |
break; |
2884 |
} |
2885 |
if ((r != null || (r = fst.result) != null || |
2886 |
(r = snd.result) != null) && |
2887 |
(d == null || d.compareAndSet(0, 1))) { |
2888 |
Throwable ex; Object t; |
2889 |
if (r instanceof AltResult) { |
2890 |
ex = ((AltResult)r).ex; |
2891 |
t = null; |
2892 |
} |
2893 |
else { |
2894 |
ex = null; |
2895 |
t = r; |
2896 |
} |
2897 |
dst.internalComplete(t, ex); |
2898 |
} |
2899 |
fst.helpPostComplete(); |
2900 |
snd.helpPostComplete(); |
2901 |
return dst; |
2902 |
} |
2903 |
|
2904 |
/* ------------- Control and status methods -------------- */ |
2905 |
|
2906 |
/** |
2907 |
* If not already completed, completes this CompletableFuture with |
2908 |
* a {@link CancellationException}. Dependent CompletableFutures |
2909 |
* that have not already completed will also complete |
2910 |
* exceptionally, with a {@link CompletionException} caused by |
2911 |
* this {@code CancellationException}. |
2912 |
* |
2913 |
* @param mayInterruptIfRunning this value has no effect in this |
2914 |
* implementation because interrupts are not used to control |
2915 |
* processing. |
2916 |
* |
2917 |
* @return {@code true} if this task is now cancelled |
2918 |
*/ |
2919 |
public boolean cancel(boolean mayInterruptIfRunning) { |
2920 |
boolean cancelled = (result == null) && |
2921 |
UNSAFE.compareAndSwapObject |
2922 |
(this, RESULT, null, new AltResult(new CancellationException())); |
2923 |
postComplete(); |
2924 |
return cancelled || isCancelled(); |
2925 |
} |
2926 |
|
2927 |
/** |
2928 |
* Returns {@code true} if this CompletableFuture was cancelled |
2929 |
* before it completed normally. |
2930 |
* |
2931 |
* @return {@code true} if this CompletableFuture was cancelled |
2932 |
* before it completed normally |
2933 |
*/ |
2934 |
public boolean isCancelled() { |
2935 |
Object r; |
2936 |
return ((r = result) instanceof AltResult) && |
2937 |
(((AltResult)r).ex instanceof CancellationException); |
2938 |
} |
2939 |
|
2940 |
/** |
2941 |
* Returns {@code true} if this CompletableFuture completed |
2942 |
* exceptionally, in any way. Possible causes include |
2943 |
* cancellation, explicit invocation of {@code |
2944 |
* completeExceptionally}, and abrupt termination of a |
2945 |
* CompletionStage action. |
2946 |
* |
2947 |
* @return {@code true} if this CompletableFuture completed |
2948 |
* exceptionally |
2949 |
*/ |
2950 |
public boolean isCompletedExceptionally() { |
2951 |
Object r; |
2952 |
return ((r = result) instanceof AltResult) && r != NIL; |
2953 |
} |
2954 |
|
2955 |
/** |
2956 |
* Forcibly sets or resets the value subsequently returned by |
2957 |
* method {@link #get()} and related methods, whether or not |
2958 |
* already completed. This method is designed for use only in |
2959 |
* error recovery actions, and even in such situations may result |
2960 |
* in ongoing dependent completions using established versus |
2961 |
* overwritten outcomes. |
2962 |
* |
2963 |
* @param value the completion value |
2964 |
*/ |
2965 |
public void obtrudeValue(T value) { |
2966 |
result = (value == null) ? NIL : value; |
2967 |
postComplete(); |
2968 |
} |
2969 |
|
2970 |
/** |
2971 |
* Forcibly causes subsequent invocations of method {@link #get()} |
2972 |
* and related methods to throw the given exception, whether or |
2973 |
* not already completed. This method is designed for use only in |
2974 |
* recovery actions, and even in such situations may result in |
2975 |
* ongoing dependent completions using established versus |
2976 |
* overwritten outcomes. |
2977 |
* |
2978 |
* @param ex the exception |
2979 |
*/ |
2980 |
public void obtrudeException(Throwable ex) { |
2981 |
if (ex == null) throw new NullPointerException(); |
2982 |
result = new AltResult(ex); |
2983 |
postComplete(); |
2984 |
} |
2985 |
|
2986 |
/** |
2987 |
* Returns the estimated number of CompletableFutures whose |
2988 |
* completions are awaiting completion of this CompletableFuture. |
2989 |
* This method is designed for use in monitoring system state, not |
2990 |
* for synchronization control. |
2991 |
* |
2992 |
* @return the number of dependent CompletableFutures |
2993 |
*/ |
2994 |
public int getNumberOfDependents() { |
2995 |
int count = 0; |
2996 |
for (CompletionNode p = completions; p != null; p = p.next) |
2997 |
++count; |
2998 |
return count; |
2999 |
} |
3000 |
|
3001 |
/** |
3002 |
* Returns a string identifying this CompletableFuture, as well as |
3003 |
* its completion state. The state, in brackets, contains the |
3004 |
* String {@code "Completed Normally"} or the String {@code |
3005 |
* "Completed Exceptionally"}, or the String {@code "Not |
3006 |
* completed"} followed by the number of CompletableFutures |
3007 |
* dependent upon its completion, if any. |
3008 |
* |
3009 |
* @return a string identifying this CompletableFuture, as well as its state |
3010 |
*/ |
3011 |
public String toString() { |
3012 |
Object r = result; |
3013 |
int count; |
3014 |
return super.toString() + |
3015 |
((r == null) ? |
3016 |
(((count = getNumberOfDependents()) == 0) ? |
3017 |
"[Not completed]" : |
3018 |
"[Not completed, " + count + " dependents]") : |
3019 |
(((r instanceof AltResult) && ((AltResult)r).ex != null) ? |
3020 |
"[Completed exceptionally]" : |
3021 |
"[Completed normally]")); |
3022 |
} |
3023 |
|
3024 |
// Unsafe mechanics |
3025 |
private static final sun.misc.Unsafe UNSAFE; |
3026 |
private static final long RESULT; |
3027 |
private static final long WAITERS; |
3028 |
private static final long COMPLETIONS; |
3029 |
static { |
3030 |
try { |
3031 |
UNSAFE = sun.misc.Unsafe.getUnsafe(); |
3032 |
Class<?> k = CompletableFuture.class; |
3033 |
RESULT = UNSAFE.objectFieldOffset |
3034 |
(k.getDeclaredField("result")); |
3035 |
WAITERS = UNSAFE.objectFieldOffset |
3036 |
(k.getDeclaredField("waiters")); |
3037 |
COMPLETIONS = UNSAFE.objectFieldOffset |
3038 |
(k.getDeclaredField("completions")); |
3039 |
} catch (Exception e) { |
3040 |
throw new Error(e); |
3041 |
} |
3042 |
} |
3043 |
} |