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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 of an observable CF is triggered. (We |
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* could even use the same stack as for waiters, but would give up |
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* the potential parallelism obtained because woken waiters help |
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* release/run others -- see method postComplete). Because |
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* post-processing may race with direct calls, class Completion |
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* opportunistically extends AtomicInteger so callers can claim |
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* the action via compareAndSet(0, 1). The Completion.tryComplete |
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* methods are all written a boringly similar uniform way (that |
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* sometimes includes unnecessary-looking checks, kept to maintain |
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* uniformity). There are enough dimensions upon which they |
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* differ that attempts to factor commonalities while maintaining |
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* efficiency 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 internalComplete(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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* Signals waiters and triggers all enabled dependent completions |
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* reachable from src. |
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* |
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* @param src if non-null a completed CompletableFuture |
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*/ |
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static final void postComplete(CompletableFuture<?> src) { |
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/* |
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* CF "src" is always the base of a possible chain of |
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* completions that may need further processing. To avoid |
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* potential StackOverflowErrors, we extend along only one |
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* path ("dep") at a time, holding others by pushing them on |
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* src's completion list, which advances tail-recursion style |
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* when possible. On each step, "f" is dep if non-null, else |
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* src. |
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*/ |
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for (CompletableFuture<?> f = src, dep = null; f != null;) { |
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WaitNode q; CompletionNode h; Thread w; |
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if ((q = f.waiters) != null) { |
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if (UNSAFE.compareAndSwapObject(f, WAITERS, q, q.next) && |
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(w = q.thread) != null) { |
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q.thread = null; |
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LockSupport.unpark(w); |
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} |
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} |
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else if ((h = f.completions) == null) { |
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if (dep == null) |
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break; |
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dep = null; |
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f = src; |
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} |
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else if (UNSAFE.compareAndSwapObject(f, COMPLETIONS, h, h.next)) { |
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Completion c; CompletableFuture<?> d; |
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if (dep != null && dep.completions != null) { // push to src |
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do {} while (!UNSAFE.compareAndSwapObject( |
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src, COMPLETIONS, |
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h.next = src.completions, h)); |
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} |
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else if ((c = h.completion) == null || |
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(d = c.tryComplete()) == null || |
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d.result == null) { |
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dep = null; |
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f = src; |
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} |
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else if (src.completions == null) { |
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dep = null; |
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f = src = d; |
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} |
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else |
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f = dep = d; |
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} |
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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() { |
247 |
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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} |
260 |
return false; |
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} |
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public boolean block() { |
263 |
if (isReleasable()) |
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return true; |
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else if (deadline == 0L) |
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LockSupport.park(this); |
267 |
else if (nanos > 0L) |
268 |
LockSupport.parkNanos(this, nanos); |
269 |
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 |
275 |
* interrupted. |
276 |
*/ |
277 |
private Object waitingGet(boolean interruptible) { |
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WaitNode q = null; |
279 |
boolean queued = false; |
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int spins = SPINS; |
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for (Object r;;) { |
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if ((r = result) != null) { |
283 |
if (q != null) { // suppress unpark |
284 |
q.thread = null; |
285 |
if (q.interruptControl < 0) { |
286 |
if (interruptible) { |
287 |
removeCancelledWaiters(); |
288 |
return null; |
289 |
} |
290 |
Thread.currentThread().interrupt(); |
291 |
} |
292 |
} |
293 |
postComplete(this); // help release others |
294 |
return r; |
295 |
} |
296 |
else if (spins > 0) { |
297 |
int rnd = ThreadLocalRandom.nextSecondarySeed(); |
298 |
if (rnd == 0) |
299 |
rnd = ThreadLocalRandom.current().nextInt(); |
300 |
if (rnd >= 0) |
301 |
--spins; |
302 |
} |
303 |
else if (q == null) |
304 |
q = new WaitNode(interruptible, 0L, 0L); |
305 |
else if (!queued) |
306 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
307 |
q.next = waiters, q); |
308 |
else if (interruptible && q.interruptControl < 0) { |
309 |
q.thread = null; |
310 |
removeCancelledWaiters(); |
311 |
return null; |
312 |
} |
313 |
else if (q.thread != null && result == null) { |
314 |
try { |
315 |
ForkJoinPool.managedBlock(q); |
316 |
} catch (InterruptedException ex) { |
317 |
q.interruptControl = -1; |
318 |
} |
319 |
} |
320 |
} |
321 |
} |
322 |
|
323 |
/** |
324 |
* Awaits completion or aborts on interrupt or timeout. |
325 |
* |
326 |
* @param nanos time to wait |
327 |
* @return raw result |
328 |
*/ |
329 |
private Object timedAwaitDone(long nanos) |
330 |
throws InterruptedException, TimeoutException { |
331 |
WaitNode q = null; |
332 |
boolean queued = false; |
333 |
for (Object r;;) { |
334 |
if ((r = result) != null) { |
335 |
if (q != null) { |
336 |
q.thread = null; |
337 |
if (q.interruptControl < 0) { |
338 |
removeCancelledWaiters(); |
339 |
throw new InterruptedException(); |
340 |
} |
341 |
} |
342 |
postComplete(this); |
343 |
return r; |
344 |
} |
345 |
else if (q == null) { |
346 |
if (nanos <= 0L) |
347 |
throw new TimeoutException(); |
348 |
long d = System.nanoTime() + nanos; |
349 |
q = new WaitNode(true, nanos, d == 0L ? 1L : d); // avoid 0 |
350 |
} |
351 |
else if (!queued) |
352 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
353 |
q.next = waiters, q); |
354 |
else if (q.interruptControl < 0) { |
355 |
q.thread = null; |
356 |
removeCancelledWaiters(); |
357 |
throw new InterruptedException(); |
358 |
} |
359 |
else if (q.nanos <= 0L) { |
360 |
if (result == null) { |
361 |
q.thread = null; |
362 |
removeCancelledWaiters(); |
363 |
throw new TimeoutException(); |
364 |
} |
365 |
} |
366 |
else if (q.thread != null && result == null) { |
367 |
try { |
368 |
ForkJoinPool.managedBlock(q); |
369 |
} catch (InterruptedException ex) { |
370 |
q.interruptControl = -1; |
371 |
} |
372 |
} |
373 |
} |
374 |
} |
375 |
|
376 |
/** |
377 |
* Tries to unlink timed-out or interrupted wait nodes to avoid |
378 |
* accumulating garbage. Internal nodes are simply unspliced |
379 |
* without CAS since it is harmless if they are traversed anyway |
380 |
* by releasers. To avoid effects of unsplicing from already |
381 |
* removed nodes, the list is retraversed in case of an apparent |
382 |
* race. This is slow when there are a lot of nodes, but we don't |
383 |
* expect lists to be long enough to outweigh higher-overhead |
384 |
* schemes. |
385 |
*/ |
386 |
private void removeCancelledWaiters() { |
387 |
retry: for (;;) { // restart on removeWaiter race |
388 |
for (WaitNode pred = null, q = waiters, s; q != null; q = s) { |
389 |
s = q.next; |
390 |
if (q.thread != null) |
391 |
pred = q; |
392 |
else if (pred != null) { |
393 |
pred.next = s; |
394 |
if (pred.thread == null) // check for race |
395 |
continue retry; |
396 |
} |
397 |
else if (!UNSAFE.compareAndSwapObject(this, WAITERS, q, s)) |
398 |
continue retry; |
399 |
} |
400 |
break; |
401 |
} |
402 |
} |
403 |
|
404 |
/* ------------- Async tasks -------------- */ |
405 |
|
406 |
/** |
407 |
* A marker interface identifying asynchronous tasks produced by |
408 |
* {@code async} methods. This may be useful for monitoring, |
409 |
* debugging, and tracking asynchronous activities. |
410 |
* |
411 |
* @since 1.8 |
412 |
*/ |
413 |
public static interface AsynchronousCompletionTask { |
414 |
} |
415 |
|
416 |
/** Base class can act as either FJ or plain Runnable */ |
417 |
@SuppressWarnings("serial") |
418 |
abstract static class Async extends ForkJoinTask<Void> |
419 |
implements Runnable, AsynchronousCompletionTask { |
420 |
public final Void getRawResult() { return null; } |
421 |
public final void setRawResult(Void v) { } |
422 |
public final void run() { exec(); } |
423 |
} |
424 |
|
425 |
/** |
426 |
* Starts the given async task using the given executor, unless |
427 |
* the executor is ForkJoinPool.commonPool and it has been |
428 |
* disabled, in which case starts a new thread. |
429 |
*/ |
430 |
static void execAsync(Executor e, Async r) { |
431 |
if (e == ForkJoinPool.commonPool() && |
432 |
ForkJoinPool.getCommonPoolParallelism() <= 1) |
433 |
new Thread(r).start(); |
434 |
else |
435 |
e.execute(r); |
436 |
} |
437 |
|
438 |
static final class AsyncRun extends Async { |
439 |
final Runnable fn; |
440 |
final CompletableFuture<Void> dst; |
441 |
AsyncRun(Runnable fn, CompletableFuture<Void> dst) { |
442 |
this.fn = fn; this.dst = dst; |
443 |
} |
444 |
public final boolean exec() { |
445 |
CompletableFuture<Void> d; Throwable ex; |
446 |
if ((d = this.dst) != null && d.result == null) { |
447 |
try { |
448 |
fn.run(); |
449 |
ex = null; |
450 |
} catch (Throwable rex) { |
451 |
ex = rex; |
452 |
} |
453 |
d.internalComplete(null, ex); |
454 |
} |
455 |
postComplete(d); |
456 |
return true; |
457 |
} |
458 |
private static final long serialVersionUID = 5232453952276885070L; |
459 |
} |
460 |
|
461 |
static final class AsyncSupply<U> extends Async { |
462 |
final Supplier<U> fn; |
463 |
final CompletableFuture<U> dst; |
464 |
AsyncSupply(Supplier<U> fn, CompletableFuture<U> dst) { |
465 |
this.fn = fn; this.dst = dst; |
466 |
} |
467 |
public final boolean exec() { |
468 |
CompletableFuture<U> d; U u; Throwable ex; |
469 |
if ((d = this.dst) != null && d.result == null) { |
470 |
try { |
471 |
u = fn.get(); |
472 |
ex = null; |
473 |
} catch (Throwable rex) { |
474 |
ex = rex; |
475 |
u = null; |
476 |
} |
477 |
d.internalComplete(u, ex); |
478 |
} |
479 |
postComplete(d); |
480 |
return true; |
481 |
} |
482 |
private static final long serialVersionUID = 5232453952276885070L; |
483 |
} |
484 |
|
485 |
static final class AsyncApply<T,U> extends Async { |
486 |
final T arg; |
487 |
final Function<? super T,? extends U> fn; |
488 |
final CompletableFuture<U> dst; |
489 |
AsyncApply(T arg, Function<? super T,? extends U> fn, |
490 |
CompletableFuture<U> dst) { |
491 |
this.arg = arg; this.fn = fn; this.dst = dst; |
492 |
} |
493 |
public final boolean exec() { |
494 |
CompletableFuture<U> d; U u; Throwable ex; |
495 |
if ((d = this.dst) != null && d.result == null) { |
496 |
try { |
497 |
u = fn.apply(arg); |
498 |
ex = null; |
499 |
} catch (Throwable rex) { |
500 |
ex = rex; |
501 |
u = null; |
502 |
} |
503 |
d.internalComplete(u, ex); |
504 |
} |
505 |
postComplete(d); |
506 |
return true; |
507 |
} |
508 |
private static final long serialVersionUID = 5232453952276885070L; |
509 |
} |
510 |
|
511 |
static final class AsyncCombine<T,U,V> extends Async { |
512 |
final T arg1; |
513 |
final U arg2; |
514 |
final BiFunction<? super T,? super U,? extends V> fn; |
515 |
final CompletableFuture<V> dst; |
516 |
AsyncCombine(T arg1, U arg2, |
517 |
BiFunction<? super T,? super U,? extends V> fn, |
518 |
CompletableFuture<V> dst) { |
519 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
520 |
} |
521 |
public final boolean exec() { |
522 |
CompletableFuture<V> d; V v; Throwable ex; |
523 |
if ((d = this.dst) != null && d.result == null) { |
524 |
try { |
525 |
v = fn.apply(arg1, arg2); |
526 |
ex = null; |
527 |
} catch (Throwable rex) { |
528 |
ex = rex; |
529 |
v = null; |
530 |
} |
531 |
d.internalComplete(v, ex); |
532 |
} |
533 |
postComplete(d); |
534 |
return true; |
535 |
} |
536 |
private static final long serialVersionUID = 5232453952276885070L; |
537 |
} |
538 |
|
539 |
static final class AsyncAccept<T> extends Async { |
540 |
final T arg; |
541 |
final Consumer<? super T> fn; |
542 |
final CompletableFuture<?> dst; |
543 |
AsyncAccept(T arg, Consumer<? super T> fn, |
544 |
CompletableFuture<?> dst) { |
545 |
this.arg = arg; this.fn = fn; this.dst = dst; |
546 |
} |
547 |
public final boolean exec() { |
548 |
CompletableFuture<?> d; Throwable ex; |
549 |
if ((d = this.dst) != null && d.result == null) { |
550 |
try { |
551 |
fn.accept(arg); |
552 |
ex = null; |
553 |
} catch (Throwable rex) { |
554 |
ex = rex; |
555 |
} |
556 |
d.internalComplete(null, ex); |
557 |
} |
558 |
postComplete(d); |
559 |
return true; |
560 |
} |
561 |
private static final long serialVersionUID = 5232453952276885070L; |
562 |
} |
563 |
|
564 |
static final class AsyncAcceptBoth<T,U> extends Async { |
565 |
final T arg1; |
566 |
final U arg2; |
567 |
final BiConsumer<? super T,? super U> fn; |
568 |
final CompletableFuture<?> dst; |
569 |
AsyncAcceptBoth(T arg1, U arg2, |
570 |
BiConsumer<? super T,? super U> fn, |
571 |
CompletableFuture<?> dst) { |
572 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
573 |
} |
574 |
public final boolean exec() { |
575 |
CompletableFuture<?> d; Throwable ex; |
576 |
if ((d = this.dst) != null && d.result == null) { |
577 |
try { |
578 |
fn.accept(arg1, arg2); |
579 |
ex = null; |
580 |
} catch (Throwable rex) { |
581 |
ex = rex; |
582 |
} |
583 |
d.internalComplete(null, ex); |
584 |
} |
585 |
postComplete(d); |
586 |
return true; |
587 |
} |
588 |
private static final long serialVersionUID = 5232453952276885070L; |
589 |
} |
590 |
|
591 |
static final class AsyncCompose<T,U> extends Async { |
592 |
final T arg; |
593 |
final Function<? super T, ? extends CompletionStage<U>> fn; |
594 |
final CompletableFuture<U> dst; |
595 |
AsyncCompose(T arg, |
596 |
Function<? super T, ? extends CompletionStage<U>> fn, |
597 |
CompletableFuture<U> dst) { |
598 |
this.arg = arg; this.fn = fn; this.dst = dst; |
599 |
} |
600 |
public final boolean exec() { |
601 |
CompletableFuture<U> d, fr; U u; Throwable ex; |
602 |
if ((d = this.dst) != null && d.result == null) { |
603 |
try { |
604 |
CompletionStage<U> cs = fn.apply(arg); |
605 |
fr = (cs == null) ? null : cs.toCompletableFuture(); |
606 |
ex = (fr == null) ? new NullPointerException() : null; |
607 |
} catch (Throwable rex) { |
608 |
ex = rex; |
609 |
fr = null; |
610 |
} |
611 |
if (ex != null) |
612 |
u = null; |
613 |
else { |
614 |
Object r = fr.result; |
615 |
if (r == null) |
616 |
r = fr.waitingGet(false); |
617 |
if (r instanceof AltResult) { |
618 |
ex = ((AltResult)r).ex; |
619 |
u = null; |
620 |
} |
621 |
else { |
622 |
@SuppressWarnings("unchecked") U ur = (U) r; |
623 |
u = ur; |
624 |
} |
625 |
} |
626 |
d.internalComplete(u, ex); |
627 |
} |
628 |
postComplete(d); |
629 |
return true; |
630 |
} |
631 |
private static final long serialVersionUID = 5232453952276885070L; |
632 |
} |
633 |
|
634 |
static final class AsyncWhenComplete<T> extends Async { |
635 |
final T arg1; |
636 |
final Throwable arg2; |
637 |
final BiConsumer<? super T,? super Throwable> fn; |
638 |
final CompletableFuture<T> dst; |
639 |
AsyncWhenComplete(T arg1, Throwable arg2, |
640 |
BiConsumer<? super T,? super Throwable> fn, |
641 |
CompletableFuture<T> dst) { |
642 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
643 |
} |
644 |
public final boolean exec() { |
645 |
CompletableFuture<T> d; |
646 |
if ((d = this.dst) != null && d.result == null) { |
647 |
Throwable ex = arg2; |
648 |
try { |
649 |
fn.accept(arg1, ex); |
650 |
} catch (Throwable rex) { |
651 |
if (ex == null) |
652 |
ex = rex; |
653 |
} |
654 |
d.internalComplete(arg1, ex); |
655 |
} |
656 |
postComplete(d); |
657 |
return true; |
658 |
} |
659 |
private static final long serialVersionUID = 5232453952276885070L; |
660 |
} |
661 |
|
662 |
/* ------------- Completions -------------- */ |
663 |
|
664 |
/** |
665 |
* Simple linked list nodes to record completions, used in |
666 |
* basically the same way as WaitNodes. (We separate nodes from |
667 |
* the Completions themselves mainly because for the And and Or |
668 |
* methods, the same Completion object resides in two lists.) |
669 |
*/ |
670 |
static final class CompletionNode { |
671 |
final Completion completion; |
672 |
volatile CompletionNode next; |
673 |
CompletionNode(Completion completion) { this.completion = completion; } |
674 |
} |
675 |
|
676 |
// Opportunistically subclass AtomicInteger to use compareAndSet to claim. |
677 |
@SuppressWarnings("serial") |
678 |
abstract static class Completion extends AtomicInteger { |
679 |
/** |
680 |
* Completes a dependent Completablefuture if enabled |
681 |
* @return the dependent Completablefuture |
682 |
*/ |
683 |
public abstract CompletableFuture<?> tryComplete(); |
684 |
} |
685 |
|
686 |
static final class ThenApply<T,U> extends Completion { |
687 |
final CompletableFuture<? extends T> src; |
688 |
final Function<? super T,? extends U> fn; |
689 |
final CompletableFuture<U> dst; |
690 |
final Executor executor; |
691 |
ThenApply(CompletableFuture<? extends T> src, |
692 |
Function<? super T,? extends U> fn, |
693 |
CompletableFuture<U> dst, |
694 |
Executor executor) { |
695 |
this.src = src; this.fn = fn; this.dst = dst; |
696 |
this.executor = executor; |
697 |
} |
698 |
public final CompletableFuture<?> tryComplete() { |
699 |
final CompletableFuture<? extends T> a; |
700 |
final Function<? super T,? extends U> fn; |
701 |
final CompletableFuture<U> dst; |
702 |
Object r; T t; Throwable ex; |
703 |
if ((dst = this.dst) != null && |
704 |
(fn = this.fn) != null && |
705 |
(a = this.src) != null && |
706 |
(r = a.result) != null && |
707 |
get() == 0 && compareAndSet(0, 1)) { |
708 |
if (r instanceof AltResult) { |
709 |
ex = ((AltResult)r).ex; |
710 |
t = null; |
711 |
} |
712 |
else { |
713 |
ex = null; |
714 |
@SuppressWarnings("unchecked") T tr = (T) r; |
715 |
t = tr; |
716 |
} |
717 |
Executor e = executor; |
718 |
U u = null; |
719 |
if (ex == null) { |
720 |
try { |
721 |
if (e != null) |
722 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
723 |
else |
724 |
u = fn.apply(t); |
725 |
} catch (Throwable rex) { |
726 |
ex = rex; |
727 |
} |
728 |
} |
729 |
if (e == null || ex != null) |
730 |
dst.internalComplete(u, ex); |
731 |
} |
732 |
return dst; |
733 |
} |
734 |
private static final long serialVersionUID = 5232453952276885070L; |
735 |
} |
736 |
|
737 |
static final class ThenAccept<T> extends Completion { |
738 |
final CompletableFuture<? extends T> src; |
739 |
final Consumer<? super T> fn; |
740 |
final CompletableFuture<?> dst; |
741 |
final Executor executor; |
742 |
ThenAccept(CompletableFuture<? extends T> src, |
743 |
Consumer<? super T> fn, |
744 |
CompletableFuture<?> dst, |
745 |
Executor executor) { |
746 |
this.src = src; this.fn = fn; this.dst = dst; |
747 |
this.executor = executor; |
748 |
} |
749 |
public final CompletableFuture<?> tryComplete() { |
750 |
final CompletableFuture<? extends T> a; |
751 |
final Consumer<? super T> fn; |
752 |
final CompletableFuture<?> dst; |
753 |
Object r; T t; Throwable ex; |
754 |
if ((dst = this.dst) != null && |
755 |
(fn = this.fn) != null && |
756 |
(a = this.src) != null && |
757 |
(r = a.result) != null && |
758 |
get() == 0 && compareAndSet(0, 1)) { |
759 |
if (r instanceof AltResult) { |
760 |
ex = ((AltResult)r).ex; |
761 |
t = null; |
762 |
} |
763 |
else { |
764 |
ex = null; |
765 |
@SuppressWarnings("unchecked") T tr = (T) r; |
766 |
t = tr; |
767 |
} |
768 |
Executor e = executor; |
769 |
if (ex == null) { |
770 |
try { |
771 |
if (e != null) |
772 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
773 |
else |
774 |
fn.accept(t); |
775 |
} catch (Throwable rex) { |
776 |
ex = rex; |
777 |
} |
778 |
} |
779 |
if (e == null || ex != null) |
780 |
dst.internalComplete(null, ex); |
781 |
} |
782 |
return dst; |
783 |
} |
784 |
private static final long serialVersionUID = 5232453952276885070L; |
785 |
} |
786 |
|
787 |
static final class ThenRun extends Completion { |
788 |
final CompletableFuture<?> src; |
789 |
final Runnable fn; |
790 |
final CompletableFuture<Void> dst; |
791 |
final Executor executor; |
792 |
ThenRun(CompletableFuture<?> src, |
793 |
Runnable fn, |
794 |
CompletableFuture<Void> dst, |
795 |
Executor executor) { |
796 |
this.src = src; this.fn = fn; this.dst = dst; |
797 |
this.executor = executor; |
798 |
} |
799 |
public final CompletableFuture<?> tryComplete() { |
800 |
final CompletableFuture<?> a; |
801 |
final Runnable fn; |
802 |
final CompletableFuture<Void> dst; |
803 |
Object r; Throwable ex; |
804 |
if ((dst = this.dst) != null && |
805 |
(fn = this.fn) != null && |
806 |
(a = this.src) != null && |
807 |
(r = a.result) != null && |
808 |
get() == 0 && compareAndSet(0, 1)) { |
809 |
if (r instanceof AltResult) |
810 |
ex = ((AltResult)r).ex; |
811 |
else |
812 |
ex = null; |
813 |
Executor e = executor; |
814 |
if (ex == null) { |
815 |
try { |
816 |
if (e != null) |
817 |
execAsync(e, new AsyncRun(fn, dst)); |
818 |
else |
819 |
fn.run(); |
820 |
} catch (Throwable rex) { |
821 |
ex = rex; |
822 |
} |
823 |
} |
824 |
if (e == null || ex != null) |
825 |
dst.internalComplete(null, ex); |
826 |
} |
827 |
return dst; |
828 |
} |
829 |
private static final long serialVersionUID = 5232453952276885070L; |
830 |
} |
831 |
|
832 |
static final class ThenCombine<T,U,V> extends Completion { |
833 |
final CompletableFuture<? extends T> src; |
834 |
final CompletableFuture<? extends U> snd; |
835 |
final BiFunction<? super T,? super U,? extends V> fn; |
836 |
final CompletableFuture<V> dst; |
837 |
final Executor executor; |
838 |
ThenCombine(CompletableFuture<? extends T> src, |
839 |
CompletableFuture<? extends U> snd, |
840 |
BiFunction<? super T,? super U,? extends V> fn, |
841 |
CompletableFuture<V> dst, |
842 |
Executor executor) { |
843 |
this.src = src; this.snd = snd; |
844 |
this.fn = fn; this.dst = dst; |
845 |
this.executor = executor; |
846 |
} |
847 |
public final CompletableFuture<?> tryComplete() { |
848 |
final CompletableFuture<? extends T> a; |
849 |
final CompletableFuture<? extends U> b; |
850 |
final BiFunction<? super T,? super U,? extends V> fn; |
851 |
final CompletableFuture<V> dst; |
852 |
Object r, s; T t; U u; Throwable ex; |
853 |
if ((dst = this.dst) != null && |
854 |
(fn = this.fn) != null && |
855 |
(a = this.src) != null && |
856 |
(r = a.result) != null && |
857 |
(b = this.snd) != null && |
858 |
(s = b.result) != null && |
859 |
get() == 0 && compareAndSet(0, 1)) { |
860 |
if (r instanceof AltResult) { |
861 |
ex = ((AltResult)r).ex; |
862 |
t = null; |
863 |
} |
864 |
else { |
865 |
ex = null; |
866 |
@SuppressWarnings("unchecked") T tr = (T) r; |
867 |
t = tr; |
868 |
} |
869 |
if (ex != null) |
870 |
u = null; |
871 |
else if (s instanceof AltResult) { |
872 |
ex = ((AltResult)s).ex; |
873 |
u = null; |
874 |
} |
875 |
else { |
876 |
@SuppressWarnings("unchecked") U us = (U) s; |
877 |
u = us; |
878 |
} |
879 |
Executor e = executor; |
880 |
V v = null; |
881 |
if (ex == null) { |
882 |
try { |
883 |
if (e != null) |
884 |
execAsync(e, new AsyncCombine<T,U,V>(t, u, fn, dst)); |
885 |
else |
886 |
v = fn.apply(t, u); |
887 |
} catch (Throwable rex) { |
888 |
ex = rex; |
889 |
} |
890 |
} |
891 |
if (e == null || ex != null) |
892 |
dst.internalComplete(v, ex); |
893 |
} |
894 |
return dst; |
895 |
} |
896 |
private static final long serialVersionUID = 5232453952276885070L; |
897 |
} |
898 |
|
899 |
static final class ThenAcceptBoth<T,U> extends Completion { |
900 |
final CompletableFuture<? extends T> src; |
901 |
final CompletableFuture<? extends U> snd; |
902 |
final BiConsumer<? super T,? super U> fn; |
903 |
final CompletableFuture<Void> dst; |
904 |
final Executor executor; |
905 |
ThenAcceptBoth(CompletableFuture<? extends T> src, |
906 |
CompletableFuture<? extends U> snd, |
907 |
BiConsumer<? super T,? super U> fn, |
908 |
CompletableFuture<Void> dst, |
909 |
Executor executor) { |
910 |
this.src = src; this.snd = snd; |
911 |
this.fn = fn; this.dst = dst; |
912 |
this.executor = executor; |
913 |
} |
914 |
public final CompletableFuture<?> tryComplete() { |
915 |
final CompletableFuture<? extends T> a; |
916 |
final CompletableFuture<? extends U> b; |
917 |
final BiConsumer<? super T,? super U> fn; |
918 |
final CompletableFuture<Void> dst; |
919 |
Object r, s; T t; U u; Throwable ex; |
920 |
if ((dst = this.dst) != null && |
921 |
(fn = this.fn) != null && |
922 |
(a = this.src) != null && |
923 |
(r = a.result) != null && |
924 |
(b = this.snd) != null && |
925 |
(s = b.result) != null && |
926 |
get() == 0 && compareAndSet(0, 1)) { |
927 |
if (r instanceof AltResult) { |
928 |
ex = ((AltResult)r).ex; |
929 |
t = null; |
930 |
} |
931 |
else { |
932 |
ex = null; |
933 |
@SuppressWarnings("unchecked") T tr = (T) r; |
934 |
t = tr; |
935 |
} |
936 |
if (ex != null) |
937 |
u = null; |
938 |
else if (s instanceof AltResult) { |
939 |
ex = ((AltResult)s).ex; |
940 |
u = null; |
941 |
} |
942 |
else { |
943 |
@SuppressWarnings("unchecked") U us = (U) s; |
944 |
u = us; |
945 |
} |
946 |
Executor e = executor; |
947 |
if (ex == null) { |
948 |
try { |
949 |
if (e != null) |
950 |
execAsync(e, new AsyncAcceptBoth<T,U>(t, u, fn, dst)); |
951 |
else |
952 |
fn.accept(t, u); |
953 |
} catch (Throwable rex) { |
954 |
ex = rex; |
955 |
} |
956 |
} |
957 |
if (e == null || ex != null) |
958 |
dst.internalComplete(null, ex); |
959 |
} |
960 |
return dst; |
961 |
} |
962 |
private static final long serialVersionUID = 5232453952276885070L; |
963 |
} |
964 |
|
965 |
static final class RunAfterBoth extends Completion { |
966 |
final CompletableFuture<?> src; |
967 |
final CompletableFuture<?> snd; |
968 |
final Runnable fn; |
969 |
final CompletableFuture<Void> dst; |
970 |
final Executor executor; |
971 |
RunAfterBoth(CompletableFuture<?> src, |
972 |
CompletableFuture<?> snd, |
973 |
Runnable fn, |
974 |
CompletableFuture<Void> dst, |
975 |
Executor executor) { |
976 |
this.src = src; this.snd = snd; |
977 |
this.fn = fn; this.dst = dst; |
978 |
this.executor = executor; |
979 |
} |
980 |
public final CompletableFuture<?> tryComplete() { |
981 |
final CompletableFuture<?> a; |
982 |
final CompletableFuture<?> b; |
983 |
final Runnable fn; |
984 |
final CompletableFuture<Void> dst; |
985 |
Object r, s; Throwable ex; |
986 |
if ((dst = this.dst) != null && |
987 |
(fn = this.fn) != null && |
988 |
(a = this.src) != null && |
989 |
(r = a.result) != null && |
990 |
(b = this.snd) != null && |
991 |
(s = b.result) != null && |
992 |
get() == 0 && compareAndSet(0, 1)) { |
993 |
if (r instanceof AltResult) |
994 |
ex = ((AltResult)r).ex; |
995 |
else |
996 |
ex = null; |
997 |
if (ex == null && (s instanceof AltResult)) |
998 |
ex = ((AltResult)s).ex; |
999 |
Executor e = executor; |
1000 |
if (ex == null) { |
1001 |
try { |
1002 |
if (e != null) |
1003 |
execAsync(e, new AsyncRun(fn, dst)); |
1004 |
else |
1005 |
fn.run(); |
1006 |
} catch (Throwable rex) { |
1007 |
ex = rex; |
1008 |
} |
1009 |
} |
1010 |
if (e == null || ex != null) |
1011 |
dst.internalComplete(null, ex); |
1012 |
} |
1013 |
return dst; |
1014 |
} |
1015 |
private static final long serialVersionUID = 5232453952276885070L; |
1016 |
} |
1017 |
|
1018 |
static final class AndCompletion extends Completion { |
1019 |
final CompletableFuture<?> src; |
1020 |
final CompletableFuture<?> snd; |
1021 |
final CompletableFuture<Void> dst; |
1022 |
AndCompletion(CompletableFuture<?> src, |
1023 |
CompletableFuture<?> snd, |
1024 |
CompletableFuture<Void> dst) { |
1025 |
this.src = src; this.snd = snd; this.dst = dst; |
1026 |
} |
1027 |
public final CompletableFuture<?> tryComplete() { |
1028 |
final CompletableFuture<?> a; |
1029 |
final CompletableFuture<?> b; |
1030 |
final CompletableFuture<Void> dst; |
1031 |
Object r, s; Throwable ex; |
1032 |
if ((dst = this.dst) != null && |
1033 |
(a = this.src) != null && |
1034 |
(r = a.result) != null && |
1035 |
(b = this.snd) != null && |
1036 |
(s = b.result) != null && |
1037 |
get() == 0 && compareAndSet(0, 1)) { |
1038 |
if (r instanceof AltResult) |
1039 |
ex = ((AltResult)r).ex; |
1040 |
else |
1041 |
ex = null; |
1042 |
if (ex == null && (s instanceof AltResult)) |
1043 |
ex = ((AltResult)s).ex; |
1044 |
dst.internalComplete(null, ex); |
1045 |
} |
1046 |
return dst; |
1047 |
} |
1048 |
private static final long serialVersionUID = 5232453952276885070L; |
1049 |
} |
1050 |
|
1051 |
static final class ApplyToEither<T,U> extends Completion { |
1052 |
final CompletableFuture<? extends T> src; |
1053 |
final CompletableFuture<? extends T> snd; |
1054 |
final Function<? super T,? extends U> fn; |
1055 |
final CompletableFuture<U> dst; |
1056 |
final Executor executor; |
1057 |
ApplyToEither(CompletableFuture<? extends T> src, |
1058 |
CompletableFuture<? extends T> snd, |
1059 |
Function<? super T,? extends U> fn, |
1060 |
CompletableFuture<U> dst, |
1061 |
Executor executor) { |
1062 |
this.src = src; this.snd = snd; |
1063 |
this.fn = fn; this.dst = dst; |
1064 |
this.executor = executor; |
1065 |
} |
1066 |
public final CompletableFuture<?> tryComplete() { |
1067 |
final CompletableFuture<? extends T> a; |
1068 |
final CompletableFuture<? extends T> b; |
1069 |
final Function<? super T,? extends U> fn; |
1070 |
final CompletableFuture<U> dst; |
1071 |
Object r; T t; Throwable ex; |
1072 |
if ((dst = this.dst) != null && |
1073 |
(fn = this.fn) != null && |
1074 |
(((a = this.src) != null && (r = a.result) != null) || |
1075 |
((b = this.snd) != null && (r = b.result) != null)) && |
1076 |
get() == 0 && compareAndSet(0, 1)) { |
1077 |
if (r instanceof AltResult) { |
1078 |
ex = ((AltResult)r).ex; |
1079 |
t = null; |
1080 |
} |
1081 |
else { |
1082 |
ex = null; |
1083 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1084 |
t = tr; |
1085 |
} |
1086 |
Executor e = executor; |
1087 |
U u = null; |
1088 |
if (ex == null) { |
1089 |
try { |
1090 |
if (e != null) |
1091 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
1092 |
else |
1093 |
u = fn.apply(t); |
1094 |
} catch (Throwable rex) { |
1095 |
ex = rex; |
1096 |
} |
1097 |
} |
1098 |
if (e == null || ex != null) |
1099 |
dst.internalComplete(u, ex); |
1100 |
} |
1101 |
return dst; |
1102 |
} |
1103 |
private static final long serialVersionUID = 5232453952276885070L; |
1104 |
} |
1105 |
|
1106 |
static final class AcceptEither<T> extends Completion { |
1107 |
final CompletableFuture<? extends T> src; |
1108 |
final CompletableFuture<? extends T> snd; |
1109 |
final Consumer<? super T> fn; |
1110 |
final CompletableFuture<Void> dst; |
1111 |
final Executor executor; |
1112 |
AcceptEither(CompletableFuture<? extends T> src, |
1113 |
CompletableFuture<? extends T> snd, |
1114 |
Consumer<? super T> fn, |
1115 |
CompletableFuture<Void> dst, |
1116 |
Executor executor) { |
1117 |
this.src = src; this.snd = snd; |
1118 |
this.fn = fn; this.dst = dst; |
1119 |
this.executor = executor; |
1120 |
} |
1121 |
public final CompletableFuture<?> tryComplete() { |
1122 |
final CompletableFuture<? extends T> a; |
1123 |
final CompletableFuture<? extends T> b; |
1124 |
final Consumer<? super T> fn; |
1125 |
final CompletableFuture<Void> dst; |
1126 |
Object r; T t; Throwable ex; |
1127 |
if ((dst = this.dst) != null && |
1128 |
(fn = this.fn) != null && |
1129 |
(((a = this.src) != null && (r = a.result) != null) || |
1130 |
((b = this.snd) != null && (r = b.result) != null)) && |
1131 |
get() == 0 && compareAndSet(0, 1)) { |
1132 |
if (r instanceof AltResult) { |
1133 |
ex = ((AltResult)r).ex; |
1134 |
t = null; |
1135 |
} |
1136 |
else { |
1137 |
ex = null; |
1138 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1139 |
t = tr; |
1140 |
} |
1141 |
Executor e = executor; |
1142 |
if (ex == null) { |
1143 |
try { |
1144 |
if (e != null) |
1145 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
1146 |
else |
1147 |
fn.accept(t); |
1148 |
} catch (Throwable rex) { |
1149 |
ex = rex; |
1150 |
} |
1151 |
} |
1152 |
if (e == null || ex != null) |
1153 |
dst.internalComplete(null, ex); |
1154 |
} |
1155 |
return dst; |
1156 |
} |
1157 |
private static final long serialVersionUID = 5232453952276885070L; |
1158 |
} |
1159 |
|
1160 |
static final class RunAfterEither extends Completion { |
1161 |
final CompletableFuture<?> src; |
1162 |
final CompletableFuture<?> snd; |
1163 |
final Runnable fn; |
1164 |
final CompletableFuture<Void> dst; |
1165 |
final Executor executor; |
1166 |
RunAfterEither(CompletableFuture<?> src, |
1167 |
CompletableFuture<?> snd, |
1168 |
Runnable fn, |
1169 |
CompletableFuture<Void> dst, |
1170 |
Executor executor) { |
1171 |
this.src = src; this.snd = snd; |
1172 |
this.fn = fn; this.dst = dst; |
1173 |
this.executor = executor; |
1174 |
} |
1175 |
public final CompletableFuture<?> tryComplete() { |
1176 |
final CompletableFuture<?> a; |
1177 |
final CompletableFuture<?> b; |
1178 |
final Runnable fn; |
1179 |
final CompletableFuture<Void> dst; |
1180 |
Object r; Throwable ex; |
1181 |
if ((dst = this.dst) != null && |
1182 |
(fn = this.fn) != null && |
1183 |
(((a = this.src) != null && (r = a.result) != null) || |
1184 |
((b = this.snd) != null && (r = b.result) != null)) && |
1185 |
get() == 0 && compareAndSet(0, 1)) { |
1186 |
if (r instanceof AltResult) |
1187 |
ex = ((AltResult)r).ex; |
1188 |
else |
1189 |
ex = null; |
1190 |
Executor e = executor; |
1191 |
if (ex == null) { |
1192 |
try { |
1193 |
if (e != null) |
1194 |
execAsync(e, new AsyncRun(fn, dst)); |
1195 |
else |
1196 |
fn.run(); |
1197 |
} catch (Throwable rex) { |
1198 |
ex = rex; |
1199 |
} |
1200 |
} |
1201 |
if (e == null || ex != null) |
1202 |
dst.internalComplete(null, ex); |
1203 |
} |
1204 |
return dst; |
1205 |
} |
1206 |
private static final long serialVersionUID = 5232453952276885070L; |
1207 |
} |
1208 |
|
1209 |
static final class OrCompletion extends Completion { |
1210 |
final CompletableFuture<?> src; |
1211 |
final CompletableFuture<?> snd; |
1212 |
final CompletableFuture<Object> dst; |
1213 |
OrCompletion(CompletableFuture<?> src, |
1214 |
CompletableFuture<?> snd, |
1215 |
CompletableFuture<Object> dst) { |
1216 |
this.src = src; this.snd = snd; this.dst = dst; |
1217 |
} |
1218 |
public final CompletableFuture<?> tryComplete() { |
1219 |
final CompletableFuture<?> a; |
1220 |
final CompletableFuture<?> b; |
1221 |
final CompletableFuture<Object> dst; |
1222 |
Object r, t; Throwable ex; |
1223 |
if ((dst = this.dst) != null && |
1224 |
(((a = this.src) != null && (r = a.result) != null) || |
1225 |
((b = this.snd) != null && (r = b.result) != null)) && |
1226 |
get() == 0 && compareAndSet(0, 1)) { |
1227 |
if (r instanceof AltResult) { |
1228 |
ex = ((AltResult)r).ex; |
1229 |
t = null; |
1230 |
} |
1231 |
else { |
1232 |
ex = null; |
1233 |
t = r; |
1234 |
} |
1235 |
dst.internalComplete(t, ex); |
1236 |
} |
1237 |
return dst; |
1238 |
} |
1239 |
private static final long serialVersionUID = 5232453952276885070L; |
1240 |
} |
1241 |
|
1242 |
static final class ExceptionCompletion<T> extends Completion { |
1243 |
final CompletableFuture<? extends T> src; |
1244 |
final Function<? super Throwable, ? extends T> fn; |
1245 |
final CompletableFuture<T> dst; |
1246 |
ExceptionCompletion(CompletableFuture<? extends T> src, |
1247 |
Function<? super Throwable, ? extends T> fn, |
1248 |
CompletableFuture<T> dst) { |
1249 |
this.src = src; this.fn = fn; this.dst = dst; |
1250 |
} |
1251 |
public final CompletableFuture<?> tryComplete() { |
1252 |
final CompletableFuture<? extends T> a; |
1253 |
final Function<? super Throwable, ? extends T> fn; |
1254 |
final CompletableFuture<T> dst; |
1255 |
Object r; T t = null; Throwable ex, dx = null; |
1256 |
if ((dst = this.dst) != null && |
1257 |
(fn = this.fn) != null && |
1258 |
(a = this.src) != null && |
1259 |
(r = a.result) != null && |
1260 |
get() == 0 && compareAndSet(0, 1)) { |
1261 |
if ((r instanceof AltResult) && |
1262 |
(ex = ((AltResult)r).ex) != null) { |
1263 |
try { |
1264 |
t = fn.apply(ex); |
1265 |
} catch (Throwable rex) { |
1266 |
dx = rex; |
1267 |
} |
1268 |
} |
1269 |
else { |
1270 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1271 |
t = tr; |
1272 |
} |
1273 |
dst.internalComplete(t, dx); |
1274 |
} |
1275 |
return dst; |
1276 |
} |
1277 |
private static final long serialVersionUID = 5232453952276885070L; |
1278 |
} |
1279 |
|
1280 |
static final class WhenCompleteCompletion<T> extends Completion { |
1281 |
final CompletableFuture<? extends T> src; |
1282 |
final BiConsumer<? super T, ? super Throwable> fn; |
1283 |
final CompletableFuture<T> dst; |
1284 |
final Executor executor; |
1285 |
WhenCompleteCompletion(CompletableFuture<? extends T> src, |
1286 |
BiConsumer<? super T, ? super Throwable> fn, |
1287 |
CompletableFuture<T> dst, |
1288 |
Executor executor) { |
1289 |
this.src = src; this.fn = fn; this.dst = dst; |
1290 |
this.executor = executor; |
1291 |
} |
1292 |
public final CompletableFuture<?> tryComplete() { |
1293 |
final CompletableFuture<? extends T> a; |
1294 |
final BiConsumer<? super T, ? super Throwable> fn; |
1295 |
final CompletableFuture<T> dst; |
1296 |
Object r; T t; Throwable ex; |
1297 |
if ((dst = this.dst) != null && |
1298 |
(fn = this.fn) != null && |
1299 |
(a = this.src) != null && |
1300 |
(r = a.result) != null && |
1301 |
get() == 0 && compareAndSet(0, 1)) { |
1302 |
if (r instanceof AltResult) { |
1303 |
ex = ((AltResult)r).ex; |
1304 |
t = null; |
1305 |
} |
1306 |
else { |
1307 |
ex = null; |
1308 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1309 |
t = tr; |
1310 |
} |
1311 |
Executor e = executor; |
1312 |
Throwable dx = null; |
1313 |
try { |
1314 |
if (e != null) |
1315 |
execAsync(e, new AsyncWhenComplete<T>(t, ex, fn, dst)); |
1316 |
else |
1317 |
fn.accept(t, ex); |
1318 |
} catch (Throwable rex) { |
1319 |
dx = rex; |
1320 |
} |
1321 |
if (e == null || dx != null) |
1322 |
dst.internalComplete(t, ex != null ? ex : dx); |
1323 |
} |
1324 |
return dst; |
1325 |
} |
1326 |
private static final long serialVersionUID = 5232453952276885070L; |
1327 |
} |
1328 |
|
1329 |
static final class ThenCopy<T> extends Completion { |
1330 |
final CompletableFuture<?> src; |
1331 |
final CompletableFuture<T> dst; |
1332 |
ThenCopy(CompletableFuture<?> src, |
1333 |
CompletableFuture<T> dst) { |
1334 |
this.src = src; this.dst = dst; |
1335 |
} |
1336 |
public final CompletableFuture<?> tryComplete() { |
1337 |
final CompletableFuture<?> a; |
1338 |
final CompletableFuture<T> dst; |
1339 |
Object r; T t; Throwable ex; |
1340 |
if ((dst = this.dst) != null && |
1341 |
(a = this.src) != null && |
1342 |
(r = a.result) != null && |
1343 |
get() == 0 && compareAndSet(0, 1)) { |
1344 |
if (r instanceof AltResult) { |
1345 |
ex = ((AltResult)r).ex; |
1346 |
t = null; |
1347 |
} |
1348 |
else { |
1349 |
ex = null; |
1350 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1351 |
t = tr; |
1352 |
} |
1353 |
dst.internalComplete(t, ex); |
1354 |
} |
1355 |
return dst; |
1356 |
} |
1357 |
private static final long serialVersionUID = 5232453952276885070L; |
1358 |
} |
1359 |
|
1360 |
// version of ThenCopy for CompletableFuture<Void> dst |
1361 |
static final class ThenPropagate extends Completion { |
1362 |
final CompletableFuture<?> src; |
1363 |
final CompletableFuture<Void> dst; |
1364 |
ThenPropagate(CompletableFuture<?> src, |
1365 |
CompletableFuture<Void> dst) { |
1366 |
this.src = src; this.dst = dst; |
1367 |
} |
1368 |
public final CompletableFuture<?> tryComplete() { |
1369 |
final CompletableFuture<?> a; |
1370 |
final CompletableFuture<Void> dst; |
1371 |
Object r; Throwable ex; |
1372 |
if ((dst = this.dst) != null && |
1373 |
(a = this.src) != null && |
1374 |
(r = a.result) != null && |
1375 |
get() == 0 && compareAndSet(0, 1)) { |
1376 |
if (r instanceof AltResult) |
1377 |
ex = ((AltResult)r).ex; |
1378 |
else |
1379 |
ex = null; |
1380 |
dst.internalComplete(null, ex); |
1381 |
} |
1382 |
return dst; |
1383 |
} |
1384 |
private static final long serialVersionUID = 5232453952276885070L; |
1385 |
} |
1386 |
|
1387 |
static final class HandleCompletion<T,U> extends Completion { |
1388 |
final CompletableFuture<? extends T> src; |
1389 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1390 |
final CompletableFuture<U> dst; |
1391 |
final Executor executor; |
1392 |
HandleCompletion(CompletableFuture<? extends T> src, |
1393 |
BiFunction<? super T, Throwable, ? extends U> fn, |
1394 |
CompletableFuture<U> dst, |
1395 |
Executor executor) { |
1396 |
this.src = src; this.fn = fn; this.dst = dst; |
1397 |
this.executor = executor; |
1398 |
} |
1399 |
public final CompletableFuture<?> tryComplete() { |
1400 |
final CompletableFuture<? extends T> a; |
1401 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1402 |
final CompletableFuture<U> dst; |
1403 |
Object r; T t; Throwable ex; |
1404 |
if ((dst = this.dst) != null && |
1405 |
(fn = this.fn) != null && |
1406 |
(a = this.src) != null && |
1407 |
(r = a.result) != null && |
1408 |
get() == 0 && compareAndSet(0, 1)) { |
1409 |
if (r instanceof AltResult) { |
1410 |
ex = ((AltResult)r).ex; |
1411 |
t = null; |
1412 |
} |
1413 |
else { |
1414 |
ex = null; |
1415 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1416 |
t = tr; |
1417 |
} |
1418 |
Executor e = executor; |
1419 |
U u = null; |
1420 |
Throwable dx = null; |
1421 |
try { |
1422 |
if (e != null) |
1423 |
execAsync(e, new AsyncCombine<T,Throwable,U>(t, ex, fn, dst)); |
1424 |
else |
1425 |
u = fn.apply(t, ex); |
1426 |
} catch (Throwable rex) { |
1427 |
dx = rex; |
1428 |
} |
1429 |
if (e == null || dx != null) |
1430 |
dst.internalComplete(u, dx); |
1431 |
} |
1432 |
return dst; |
1433 |
} |
1434 |
private static final long serialVersionUID = 5232453952276885070L; |
1435 |
} |
1436 |
|
1437 |
static final class ThenCompose<T,U> extends Completion { |
1438 |
final CompletableFuture<? extends T> src; |
1439 |
final Function<? super T, ? extends CompletionStage<U>> fn; |
1440 |
final CompletableFuture<U> dst; |
1441 |
final Executor executor; |
1442 |
ThenCompose(CompletableFuture<? extends T> src, |
1443 |
Function<? super T, ? extends CompletionStage<U>> fn, |
1444 |
CompletableFuture<U> dst, |
1445 |
Executor executor) { |
1446 |
this.src = src; this.fn = fn; this.dst = dst; |
1447 |
this.executor = executor; |
1448 |
} |
1449 |
public final CompletableFuture<?> tryComplete() { |
1450 |
final CompletableFuture<? extends T> a; |
1451 |
final Function<? super T, ? extends CompletionStage<U>> fn; |
1452 |
final CompletableFuture<U> dst; |
1453 |
Object r; T t; Throwable ex; Executor e; |
1454 |
if ((dst = this.dst) != null && |
1455 |
(fn = this.fn) != null && |
1456 |
(a = this.src) != null && |
1457 |
(r = a.result) != null && |
1458 |
get() == 0 && compareAndSet(0, 1)) { |
1459 |
if (r instanceof AltResult) { |
1460 |
ex = ((AltResult)r).ex; |
1461 |
t = null; |
1462 |
} |
1463 |
else { |
1464 |
ex = null; |
1465 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1466 |
t = tr; |
1467 |
} |
1468 |
CompletableFuture<U> c = null; |
1469 |
U u = null; |
1470 |
boolean complete = false; |
1471 |
if (ex == null) { |
1472 |
if ((e = executor) != null) |
1473 |
execAsync(e, new AsyncCompose<T,U>(t, fn, dst)); |
1474 |
else { |
1475 |
try { |
1476 |
CompletionStage<U> cs = fn.apply(t); |
1477 |
c = (cs == null) ? null : cs.toCompletableFuture(); |
1478 |
if (c == null) |
1479 |
ex = new NullPointerException(); |
1480 |
} catch (Throwable rex) { |
1481 |
ex = rex; |
1482 |
} |
1483 |
} |
1484 |
} |
1485 |
if (c != null) { |
1486 |
Object s; |
1487 |
if ((s = c.result) == null) { |
1488 |
ThenCopy<U> d = new ThenCopy<U>(c, dst); |
1489 |
CompletionNode p = new CompletionNode(d); |
1490 |
while ((s = c.result) == null) { |
1491 |
if (UNSAFE.compareAndSwapObject |
1492 |
(c, COMPLETIONS, p.next = c.completions, p)) |
1493 |
break; |
1494 |
} |
1495 |
d.tryComplete(); |
1496 |
} |
1497 |
else { |
1498 |
complete = true; |
1499 |
if (s instanceof AltResult) { |
1500 |
ex = ((AltResult)s).ex; // no rewrap |
1501 |
u = null; |
1502 |
} |
1503 |
else { |
1504 |
@SuppressWarnings("unchecked") U us = (U) s; |
1505 |
u = us; |
1506 |
} |
1507 |
} |
1508 |
} |
1509 |
if (complete || ex != null) |
1510 |
dst.internalComplete(u, ex); |
1511 |
} |
1512 |
return dst; |
1513 |
} |
1514 |
private static final long serialVersionUID = 5232453952276885070L; |
1515 |
} |
1516 |
|
1517 |
// Implementations of stage methods with (plain, async, Executor) forms |
1518 |
|
1519 |
private <U> CompletableFuture<U> doThenApply |
1520 |
(Function<? super T,? extends U> fn, |
1521 |
Executor e) { |
1522 |
if (fn == null) throw new NullPointerException(); |
1523 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
1524 |
Object r; |
1525 |
if ((r = result) == null) { |
1526 |
ThenApply<T,U> d = new ThenApply<T,U>(this, fn, dst, e); |
1527 |
CompletionNode p = new CompletionNode(d); |
1528 |
while (result == null) { |
1529 |
if (UNSAFE.compareAndSwapObject |
1530 |
(this, COMPLETIONS, p.next = completions, p)) |
1531 |
break; |
1532 |
} |
1533 |
d.tryComplete(); |
1534 |
} |
1535 |
else { |
1536 |
T t; Throwable ex; |
1537 |
if (r instanceof AltResult) { |
1538 |
ex = ((AltResult)r).ex; |
1539 |
t = null; |
1540 |
} |
1541 |
else { |
1542 |
ex = null; |
1543 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1544 |
t = tr; |
1545 |
} |
1546 |
U u = null; |
1547 |
if (ex == null) { |
1548 |
try { |
1549 |
if (e != null) |
1550 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
1551 |
else |
1552 |
u = fn.apply(t); |
1553 |
} catch (Throwable rex) { |
1554 |
ex = rex; |
1555 |
} |
1556 |
} |
1557 |
if (e == null || ex != null) |
1558 |
dst.internalComplete(u, ex); |
1559 |
} |
1560 |
return dst; |
1561 |
} |
1562 |
|
1563 |
private CompletableFuture<Void> doThenAccept(Consumer<? super T> fn, |
1564 |
Executor e) { |
1565 |
if (fn == null) throw new NullPointerException(); |
1566 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1567 |
Object r; |
1568 |
if ((r = result) == null) { |
1569 |
ThenAccept<T> d = new ThenAccept<T>(this, fn, dst, e); |
1570 |
CompletionNode p = new CompletionNode(d); |
1571 |
while (result == null) { |
1572 |
if (UNSAFE.compareAndSwapObject |
1573 |
(this, COMPLETIONS, p.next = completions, p)) |
1574 |
break; |
1575 |
} |
1576 |
d.tryComplete(); |
1577 |
} |
1578 |
else { |
1579 |
T t; Throwable ex; |
1580 |
if (r instanceof AltResult) { |
1581 |
ex = ((AltResult)r).ex; |
1582 |
t = null; |
1583 |
} |
1584 |
else { |
1585 |
ex = null; |
1586 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1587 |
t = tr; |
1588 |
} |
1589 |
if (ex == null) { |
1590 |
try { |
1591 |
if (e != null) |
1592 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
1593 |
else |
1594 |
fn.accept(t); |
1595 |
} catch (Throwable rex) { |
1596 |
ex = rex; |
1597 |
} |
1598 |
} |
1599 |
if (e == null || ex != null) |
1600 |
dst.internalComplete(null, ex); |
1601 |
} |
1602 |
return dst; |
1603 |
} |
1604 |
|
1605 |
private CompletableFuture<Void> doThenRun(Runnable action, |
1606 |
Executor e) { |
1607 |
if (action == null) throw new NullPointerException(); |
1608 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1609 |
Object r; |
1610 |
if ((r = result) == null) { |
1611 |
ThenRun d = new ThenRun(this, action, dst, e); |
1612 |
CompletionNode p = new CompletionNode(d); |
1613 |
while (result == null) { |
1614 |
if (UNSAFE.compareAndSwapObject |
1615 |
(this, COMPLETIONS, p.next = completions, p)) |
1616 |
break; |
1617 |
} |
1618 |
d.tryComplete(); |
1619 |
} |
1620 |
else { |
1621 |
Throwable ex; |
1622 |
if (r instanceof AltResult) |
1623 |
ex = ((AltResult)r).ex; |
1624 |
else |
1625 |
ex = null; |
1626 |
if (ex == null) { |
1627 |
try { |
1628 |
if (e != null) |
1629 |
execAsync(e, new AsyncRun(action, dst)); |
1630 |
else |
1631 |
action.run(); |
1632 |
} catch (Throwable rex) { |
1633 |
ex = rex; |
1634 |
} |
1635 |
} |
1636 |
if (e == null || ex != null) |
1637 |
dst.internalComplete(null, ex); |
1638 |
} |
1639 |
return dst; |
1640 |
} |
1641 |
|
1642 |
private <U,V> CompletableFuture<V> doThenCombine |
1643 |
(CompletableFuture<? extends U> other, |
1644 |
BiFunction<? super T,? super U,? extends V> fn, |
1645 |
Executor e) { |
1646 |
if (other == null || fn == null) throw new NullPointerException(); |
1647 |
CompletableFuture<V> dst = new CompletableFuture<V>(); |
1648 |
Object r = result, s = other.result; |
1649 |
if (r == null || s == null) { |
1650 |
ThenCombine<T,U,V> d = |
1651 |
new ThenCombine<T,U,V>(this, other, fn, dst, e); |
1652 |
CompletionNode q = null, p = new CompletionNode(d); |
1653 |
while ((r == null && (r = result) == null) || |
1654 |
(s == null && (s = other.result) == null)) { |
1655 |
if (q != null) { |
1656 |
if (s != null || |
1657 |
UNSAFE.compareAndSwapObject |
1658 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1659 |
break; |
1660 |
} |
1661 |
else if (r != null || |
1662 |
UNSAFE.compareAndSwapObject |
1663 |
(this, COMPLETIONS, p.next = completions, p)) { |
1664 |
if (s != null) |
1665 |
break; |
1666 |
q = new CompletionNode(d); |
1667 |
} |
1668 |
} |
1669 |
d.tryComplete(); |
1670 |
} |
1671 |
else { |
1672 |
T t; U u; Throwable ex; |
1673 |
if (r instanceof AltResult) { |
1674 |
ex = ((AltResult)r).ex; |
1675 |
t = null; |
1676 |
} |
1677 |
else { |
1678 |
ex = null; |
1679 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1680 |
t = tr; |
1681 |
} |
1682 |
if (ex != null) |
1683 |
u = null; |
1684 |
else if (s instanceof AltResult) { |
1685 |
ex = ((AltResult)s).ex; |
1686 |
u = null; |
1687 |
} |
1688 |
else { |
1689 |
@SuppressWarnings("unchecked") U us = (U) s; |
1690 |
u = us; |
1691 |
} |
1692 |
V v = null; |
1693 |
if (ex == null) { |
1694 |
try { |
1695 |
if (e != null) |
1696 |
execAsync(e, new AsyncCombine<T,U,V>(t, u, fn, dst)); |
1697 |
else |
1698 |
v = fn.apply(t, u); |
1699 |
} catch (Throwable rex) { |
1700 |
ex = rex; |
1701 |
} |
1702 |
} |
1703 |
if (e == null || ex != null) |
1704 |
dst.internalComplete(v, ex); |
1705 |
} |
1706 |
return dst; |
1707 |
} |
1708 |
|
1709 |
private <U> CompletableFuture<Void> doThenAcceptBoth |
1710 |
(CompletableFuture<? extends U> other, |
1711 |
BiConsumer<? super T,? super U> fn, |
1712 |
Executor e) { |
1713 |
if (other == null || fn == null) throw new NullPointerException(); |
1714 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1715 |
Object r = result, s = other.result; |
1716 |
if (r == null || s == null) { |
1717 |
ThenAcceptBoth<T,U> d = |
1718 |
new ThenAcceptBoth<T,U>(this, other, fn, dst, e); |
1719 |
CompletionNode q = null, p = new CompletionNode(d); |
1720 |
while ((r == null && (r = result) == null) || |
1721 |
(s == null && (s = other.result) == null)) { |
1722 |
if (q != null) { |
1723 |
if (s != null || |
1724 |
UNSAFE.compareAndSwapObject |
1725 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1726 |
break; |
1727 |
} |
1728 |
else if (r != null || |
1729 |
UNSAFE.compareAndSwapObject |
1730 |
(this, COMPLETIONS, p.next = completions, p)) { |
1731 |
if (s != null) |
1732 |
break; |
1733 |
q = new CompletionNode(d); |
1734 |
} |
1735 |
} |
1736 |
d.tryComplete(); |
1737 |
} |
1738 |
else { |
1739 |
T t; U u; Throwable ex; |
1740 |
if (r instanceof AltResult) { |
1741 |
ex = ((AltResult)r).ex; |
1742 |
t = null; |
1743 |
} |
1744 |
else { |
1745 |
ex = null; |
1746 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1747 |
t = tr; |
1748 |
} |
1749 |
if (ex != null) |
1750 |
u = null; |
1751 |
else if (s instanceof AltResult) { |
1752 |
ex = ((AltResult)s).ex; |
1753 |
u = null; |
1754 |
} |
1755 |
else { |
1756 |
@SuppressWarnings("unchecked") U us = (U) s; |
1757 |
u = us; |
1758 |
} |
1759 |
if (ex == null) { |
1760 |
try { |
1761 |
if (e != null) |
1762 |
execAsync(e, new AsyncAcceptBoth<T,U>(t, u, fn, dst)); |
1763 |
else |
1764 |
fn.accept(t, u); |
1765 |
} catch (Throwable rex) { |
1766 |
ex = rex; |
1767 |
} |
1768 |
} |
1769 |
if (e == null || ex != null) |
1770 |
dst.internalComplete(null, ex); |
1771 |
} |
1772 |
return dst; |
1773 |
} |
1774 |
|
1775 |
private CompletableFuture<Void> doRunAfterBoth(CompletableFuture<?> other, |
1776 |
Runnable action, |
1777 |
Executor e) { |
1778 |
if (other == null || action == null) throw new NullPointerException(); |
1779 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1780 |
Object r = result, s = other.result; |
1781 |
if (r == null || s == null) { |
1782 |
RunAfterBoth d = new RunAfterBoth(this, other, action, dst, e); |
1783 |
CompletionNode q = null, p = new CompletionNode(d); |
1784 |
while ((r == null && (r = result) == null) || |
1785 |
(s == null && (s = other.result) == null)) { |
1786 |
if (q != null) { |
1787 |
if (s != null || |
1788 |
UNSAFE.compareAndSwapObject |
1789 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1790 |
break; |
1791 |
} |
1792 |
else if (r != null || |
1793 |
UNSAFE.compareAndSwapObject |
1794 |
(this, COMPLETIONS, p.next = completions, p)) { |
1795 |
if (s != null) |
1796 |
break; |
1797 |
q = new CompletionNode(d); |
1798 |
} |
1799 |
} |
1800 |
d.tryComplete(); |
1801 |
} |
1802 |
else { |
1803 |
Throwable ex; |
1804 |
if (r instanceof AltResult) |
1805 |
ex = ((AltResult)r).ex; |
1806 |
else |
1807 |
ex = null; |
1808 |
if (ex == null && (s instanceof AltResult)) |
1809 |
ex = ((AltResult)s).ex; |
1810 |
if (ex == null) { |
1811 |
try { |
1812 |
if (e != null) |
1813 |
execAsync(e, new AsyncRun(action, dst)); |
1814 |
else |
1815 |
action.run(); |
1816 |
} catch (Throwable rex) { |
1817 |
ex = rex; |
1818 |
} |
1819 |
} |
1820 |
if (e == null || ex != null) |
1821 |
dst.internalComplete(null, ex); |
1822 |
} |
1823 |
return dst; |
1824 |
} |
1825 |
|
1826 |
private <U> CompletableFuture<U> doApplyToEither |
1827 |
(CompletableFuture<? extends T> other, |
1828 |
Function<? super T, U> fn, |
1829 |
Executor e) { |
1830 |
if (other == null || fn == null) throw new NullPointerException(); |
1831 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
1832 |
Object r; |
1833 |
if ((r = result) == null && (r = other.result) == null) { |
1834 |
ApplyToEither<T,U> d = |
1835 |
new ApplyToEither<T,U>(this, other, fn, dst, e); |
1836 |
CompletionNode q = null, p = new CompletionNode(d); |
1837 |
while (result == null && other.result == null) { |
1838 |
if (q != null) { |
1839 |
if (UNSAFE.compareAndSwapObject |
1840 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1841 |
break; |
1842 |
} |
1843 |
else if (UNSAFE.compareAndSwapObject |
1844 |
(this, COMPLETIONS, p.next = completions, p)) |
1845 |
q = new CompletionNode(d); |
1846 |
} |
1847 |
d.tryComplete(); |
1848 |
} |
1849 |
else { |
1850 |
T t; Throwable ex; |
1851 |
if (r instanceof AltResult) { |
1852 |
ex = ((AltResult)r).ex; |
1853 |
t = null; |
1854 |
} |
1855 |
else { |
1856 |
ex = null; |
1857 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1858 |
t = tr; |
1859 |
} |
1860 |
U u = null; |
1861 |
if (ex == null) { |
1862 |
try { |
1863 |
if (e != null) |
1864 |
execAsync(e, new AsyncApply<T,U>(t, fn, dst)); |
1865 |
else |
1866 |
u = fn.apply(t); |
1867 |
} catch (Throwable rex) { |
1868 |
ex = rex; |
1869 |
} |
1870 |
} |
1871 |
if (e == null || ex != null) |
1872 |
dst.internalComplete(u, ex); |
1873 |
} |
1874 |
return dst; |
1875 |
} |
1876 |
|
1877 |
private CompletableFuture<Void> doAcceptEither |
1878 |
(CompletableFuture<? extends T> other, |
1879 |
Consumer<? super T> fn, |
1880 |
Executor e) { |
1881 |
if (other == null || fn == null) throw new NullPointerException(); |
1882 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1883 |
Object r; |
1884 |
if ((r = result) == null && (r = other.result) == null) { |
1885 |
AcceptEither<T> d = |
1886 |
new AcceptEither<T>(this, other, fn, dst, e); |
1887 |
CompletionNode q = null, p = new CompletionNode(d); |
1888 |
while (result == null && other.result == null) { |
1889 |
if (q != null) { |
1890 |
if (UNSAFE.compareAndSwapObject |
1891 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1892 |
break; |
1893 |
} |
1894 |
else if (UNSAFE.compareAndSwapObject |
1895 |
(this, COMPLETIONS, p.next = completions, p)) |
1896 |
q = new CompletionNode(d); |
1897 |
} |
1898 |
d.tryComplete(); |
1899 |
} |
1900 |
else { |
1901 |
T t; Throwable ex; |
1902 |
if (r instanceof AltResult) { |
1903 |
ex = ((AltResult)r).ex; |
1904 |
t = null; |
1905 |
} |
1906 |
else { |
1907 |
ex = null; |
1908 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1909 |
t = tr; |
1910 |
} |
1911 |
if (ex == null) { |
1912 |
try { |
1913 |
if (e != null) |
1914 |
execAsync(e, new AsyncAccept<T>(t, fn, dst)); |
1915 |
else |
1916 |
fn.accept(t); |
1917 |
} catch (Throwable rex) { |
1918 |
ex = rex; |
1919 |
} |
1920 |
} |
1921 |
if (e == null || ex != null) |
1922 |
dst.internalComplete(null, ex); |
1923 |
} |
1924 |
return dst; |
1925 |
} |
1926 |
|
1927 |
private CompletableFuture<Void> doRunAfterEither |
1928 |
(CompletableFuture<?> other, |
1929 |
Runnable action, |
1930 |
Executor e) { |
1931 |
if (other == null || action == null) throw new NullPointerException(); |
1932 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1933 |
Object r; |
1934 |
if ((r = result) == null && (r = other.result) == null) { |
1935 |
RunAfterEither d = |
1936 |
new RunAfterEither(this, other, action, dst, e); |
1937 |
CompletionNode q = null, p = new CompletionNode(d); |
1938 |
while (result == null && other.result == null) { |
1939 |
if (q != null) { |
1940 |
if (UNSAFE.compareAndSwapObject |
1941 |
(other, COMPLETIONS, q.next = other.completions, q)) |
1942 |
break; |
1943 |
} |
1944 |
else if (UNSAFE.compareAndSwapObject |
1945 |
(this, COMPLETIONS, p.next = completions, p)) |
1946 |
q = new CompletionNode(d); |
1947 |
} |
1948 |
d.tryComplete(); |
1949 |
} |
1950 |
else { |
1951 |
Throwable ex; |
1952 |
if (r instanceof AltResult) |
1953 |
ex = ((AltResult)r).ex; |
1954 |
else |
1955 |
ex = null; |
1956 |
if (ex == null) { |
1957 |
try { |
1958 |
if (e != null) |
1959 |
execAsync(e, new AsyncRun(action, dst)); |
1960 |
else |
1961 |
action.run(); |
1962 |
} catch (Throwable rex) { |
1963 |
ex = rex; |
1964 |
} |
1965 |
} |
1966 |
if (e == null || ex != null) |
1967 |
dst.internalComplete(null, ex); |
1968 |
} |
1969 |
return dst; |
1970 |
} |
1971 |
|
1972 |
private <U> CompletableFuture<U> doThenCompose |
1973 |
(Function<? super T, ? extends CompletionStage<U>> fn, |
1974 |
Executor e) { |
1975 |
if (fn == null) throw new NullPointerException(); |
1976 |
CompletableFuture<U> dst = null; |
1977 |
Object r; |
1978 |
if ((r = result) == null) { |
1979 |
dst = new CompletableFuture<U>(); |
1980 |
ThenCompose<T,U> d = new ThenCompose<T,U>(this, fn, dst, e); |
1981 |
CompletionNode p = new CompletionNode(d); |
1982 |
while (result == null) { |
1983 |
if (UNSAFE.compareAndSwapObject |
1984 |
(this, COMPLETIONS, p.next = completions, p)) |
1985 |
break; |
1986 |
} |
1987 |
d.tryComplete(); |
1988 |
} |
1989 |
else { |
1990 |
T t; Throwable ex; |
1991 |
if (r instanceof AltResult) { |
1992 |
ex = ((AltResult)r).ex; |
1993 |
t = null; |
1994 |
} |
1995 |
else { |
1996 |
ex = null; |
1997 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1998 |
t = tr; |
1999 |
} |
2000 |
if (ex == null) { |
2001 |
if (e != null) { |
2002 |
if (dst == null) |
2003 |
dst = new CompletableFuture<U>(); |
2004 |
execAsync(e, new AsyncCompose<T,U>(t, fn, dst)); |
2005 |
} |
2006 |
else { |
2007 |
try { |
2008 |
CompletionStage<U> cs = fn.apply(t); |
2009 |
if (cs == null || |
2010 |
(dst = cs.toCompletableFuture()) == null) |
2011 |
ex = new NullPointerException(); |
2012 |
} catch (Throwable rex) { |
2013 |
ex = rex; |
2014 |
} |
2015 |
} |
2016 |
} |
2017 |
if (dst == null) |
2018 |
dst = new CompletableFuture<U>(); |
2019 |
if (ex != null) |
2020 |
dst.internalComplete(null, ex); |
2021 |
} |
2022 |
return dst; |
2023 |
} |
2024 |
|
2025 |
private CompletableFuture<T> doWhenComplete |
2026 |
(BiConsumer<? super T, ? super Throwable> fn, |
2027 |
Executor e) { |
2028 |
if (fn == null) throw new NullPointerException(); |
2029 |
CompletableFuture<T> dst = new CompletableFuture<T>(); |
2030 |
Object r; |
2031 |
if ((r = result) == null) { |
2032 |
WhenCompleteCompletion<T> d = |
2033 |
new WhenCompleteCompletion<T>(this, fn, dst, e); |
2034 |
CompletionNode p = new CompletionNode(d); |
2035 |
while (result == null) { |
2036 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2037 |
p.next = completions, p)) |
2038 |
break; |
2039 |
} |
2040 |
d.tryComplete(); |
2041 |
} |
2042 |
else { |
2043 |
T t; Throwable ex; |
2044 |
if (r instanceof AltResult) { |
2045 |
ex = ((AltResult)r).ex; |
2046 |
t = null; |
2047 |
} |
2048 |
else { |
2049 |
ex = null; |
2050 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2051 |
t = tr; |
2052 |
} |
2053 |
Throwable dx = null; |
2054 |
try { |
2055 |
if (e != null) |
2056 |
execAsync(e, new AsyncWhenComplete<T>(t, ex, fn, dst)); |
2057 |
else |
2058 |
fn.accept(t, ex); |
2059 |
} catch (Throwable rex) { |
2060 |
dx = rex; |
2061 |
} |
2062 |
if (e == null || dx != null) |
2063 |
dst.internalComplete(t, ex != null ? ex : dx); |
2064 |
} |
2065 |
return dst; |
2066 |
} |
2067 |
|
2068 |
private <U> CompletableFuture<U> doHandle |
2069 |
(BiFunction<? super T, Throwable, ? extends U> fn, |
2070 |
Executor e) { |
2071 |
if (fn == null) throw new NullPointerException(); |
2072 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
2073 |
Object r; |
2074 |
if ((r = result) == null) { |
2075 |
HandleCompletion<T,U> d = |
2076 |
new HandleCompletion<T,U>(this, fn, dst, e); |
2077 |
CompletionNode p = new CompletionNode(d); |
2078 |
while (result == null) { |
2079 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2080 |
p.next = completions, p)) |
2081 |
break; |
2082 |
} |
2083 |
d.tryComplete(); |
2084 |
} |
2085 |
else { |
2086 |
T t; Throwable ex; |
2087 |
if (r instanceof AltResult) { |
2088 |
ex = ((AltResult)r).ex; |
2089 |
t = null; |
2090 |
} |
2091 |
else { |
2092 |
ex = null; |
2093 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2094 |
t = tr; |
2095 |
} |
2096 |
U u = null; |
2097 |
Throwable dx = null; |
2098 |
try { |
2099 |
if (e != null) |
2100 |
execAsync(e, new AsyncCombine<T,Throwable,U>(t, ex, fn, dst)); |
2101 |
else { |
2102 |
u = fn.apply(t, ex); |
2103 |
dx = null; |
2104 |
} |
2105 |
} catch (Throwable rex) { |
2106 |
dx = rex; |
2107 |
u = null; |
2108 |
} |
2109 |
if (e == null || dx != null) |
2110 |
dst.internalComplete(u, dx); |
2111 |
} |
2112 |
return dst; |
2113 |
} |
2114 |
|
2115 |
// public methods |
2116 |
|
2117 |
/** |
2118 |
* Creates a new incomplete CompletableFuture. |
2119 |
*/ |
2120 |
public CompletableFuture() { |
2121 |
} |
2122 |
|
2123 |
/** |
2124 |
* Returns a new CompletableFuture that is asynchronously completed |
2125 |
* by a task running in the {@link ForkJoinPool#commonPool()} with |
2126 |
* the value obtained by calling the given Supplier. |
2127 |
* |
2128 |
* @param supplier a function returning the value to be used |
2129 |
* to complete the returned CompletableFuture |
2130 |
* @param <U> the function's return type |
2131 |
* @return the new CompletableFuture |
2132 |
*/ |
2133 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier) { |
2134 |
if (supplier == null) throw new NullPointerException(); |
2135 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
2136 |
execAsync(ForkJoinPool.commonPool(), new AsyncSupply<U>(supplier, f)); |
2137 |
return f; |
2138 |
} |
2139 |
|
2140 |
/** |
2141 |
* Returns a new CompletableFuture that is asynchronously completed |
2142 |
* by a task running in the given executor with the value obtained |
2143 |
* by calling the given Supplier. |
2144 |
* |
2145 |
* @param supplier a function returning the value to be used |
2146 |
* to complete the returned CompletableFuture |
2147 |
* @param executor the executor to use for asynchronous execution |
2148 |
* @param <U> the function's return type |
2149 |
* @return the new CompletableFuture |
2150 |
*/ |
2151 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier, |
2152 |
Executor executor) { |
2153 |
if (executor == null || supplier == null) |
2154 |
throw new NullPointerException(); |
2155 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
2156 |
execAsync(executor, new AsyncSupply<U>(supplier, f)); |
2157 |
return f; |
2158 |
} |
2159 |
|
2160 |
/** |
2161 |
* Returns a new CompletableFuture that is asynchronously completed |
2162 |
* by a task running in the {@link ForkJoinPool#commonPool()} after |
2163 |
* it runs the given action. |
2164 |
* |
2165 |
* @param runnable the action to run before completing the |
2166 |
* returned CompletableFuture |
2167 |
* @return the new CompletableFuture |
2168 |
*/ |
2169 |
public static CompletableFuture<Void> runAsync(Runnable runnable) { |
2170 |
if (runnable == null) throw new NullPointerException(); |
2171 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
2172 |
execAsync(ForkJoinPool.commonPool(), new AsyncRun(runnable, f)); |
2173 |
return f; |
2174 |
} |
2175 |
|
2176 |
/** |
2177 |
* Returns a new CompletableFuture that is asynchronously completed |
2178 |
* by a task running in the given executor after it runs the given |
2179 |
* action. |
2180 |
* |
2181 |
* @param runnable the action to run before completing the |
2182 |
* returned CompletableFuture |
2183 |
* @param executor the executor to use for asynchronous execution |
2184 |
* @return the new CompletableFuture |
2185 |
*/ |
2186 |
public static CompletableFuture<Void> runAsync(Runnable runnable, |
2187 |
Executor executor) { |
2188 |
if (executor == null || runnable == null) |
2189 |
throw new NullPointerException(); |
2190 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
2191 |
execAsync(executor, new AsyncRun(runnable, f)); |
2192 |
return f; |
2193 |
} |
2194 |
|
2195 |
/** |
2196 |
* Returns a new CompletableFuture that is already completed with |
2197 |
* the given value. |
2198 |
* |
2199 |
* @param value the value |
2200 |
* @param <U> the type of the value |
2201 |
* @return the completed CompletableFuture |
2202 |
*/ |
2203 |
public static <U> CompletableFuture<U> completedFuture(U value) { |
2204 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
2205 |
f.result = (value == null) ? NIL : value; |
2206 |
return f; |
2207 |
} |
2208 |
|
2209 |
/** |
2210 |
* Returns {@code true} if completed in any fashion: normally, |
2211 |
* exceptionally, or via cancellation. |
2212 |
* |
2213 |
* @return {@code true} if completed |
2214 |
*/ |
2215 |
public boolean isDone() { |
2216 |
return result != null; |
2217 |
} |
2218 |
|
2219 |
/** |
2220 |
* Waits if necessary for this future to complete, and then |
2221 |
* returns its result. |
2222 |
* |
2223 |
* @return the result value |
2224 |
* @throws CancellationException if this future was cancelled |
2225 |
* @throws ExecutionException if this future completed exceptionally |
2226 |
* @throws InterruptedException if the current thread was interrupted |
2227 |
* while waiting |
2228 |
*/ |
2229 |
public T get() throws InterruptedException, ExecutionException { |
2230 |
Object r; Throwable ex, cause; |
2231 |
if ((r = result) == null && (r = waitingGet(true)) == null) |
2232 |
throw new InterruptedException(); |
2233 |
if (!(r instanceof AltResult)) { |
2234 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2235 |
return tr; |
2236 |
} |
2237 |
if ((ex = ((AltResult)r).ex) == null) |
2238 |
return null; |
2239 |
if (ex instanceof CancellationException) |
2240 |
throw (CancellationException)ex; |
2241 |
if ((ex instanceof CompletionException) && |
2242 |
(cause = ex.getCause()) != null) |
2243 |
ex = cause; |
2244 |
throw new ExecutionException(ex); |
2245 |
} |
2246 |
|
2247 |
/** |
2248 |
* Waits if necessary for at most the given time for this future |
2249 |
* to complete, and then returns its result, if available. |
2250 |
* |
2251 |
* @param timeout the maximum time to wait |
2252 |
* @param unit the time unit of the timeout argument |
2253 |
* @return the result value |
2254 |
* @throws CancellationException if this future was cancelled |
2255 |
* @throws ExecutionException if this future completed exceptionally |
2256 |
* @throws InterruptedException if the current thread was interrupted |
2257 |
* while waiting |
2258 |
* @throws TimeoutException if the wait timed out |
2259 |
*/ |
2260 |
public T get(long timeout, TimeUnit unit) |
2261 |
throws InterruptedException, ExecutionException, TimeoutException { |
2262 |
Object r; Throwable ex, cause; |
2263 |
long nanos = unit.toNanos(timeout); |
2264 |
if (Thread.interrupted()) |
2265 |
throw new InterruptedException(); |
2266 |
if ((r = result) == null) |
2267 |
r = timedAwaitDone(nanos); |
2268 |
if (!(r instanceof AltResult)) { |
2269 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2270 |
return tr; |
2271 |
} |
2272 |
if ((ex = ((AltResult)r).ex) == null) |
2273 |
return null; |
2274 |
if (ex instanceof CancellationException) |
2275 |
throw (CancellationException)ex; |
2276 |
if ((ex instanceof CompletionException) && |
2277 |
(cause = ex.getCause()) != null) |
2278 |
ex = cause; |
2279 |
throw new ExecutionException(ex); |
2280 |
} |
2281 |
|
2282 |
/** |
2283 |
* Returns the result value when complete, or throws an |
2284 |
* (unchecked) exception if completed exceptionally. To better |
2285 |
* conform with the use of common functional forms, if a |
2286 |
* computation involved in the completion of this |
2287 |
* CompletableFuture threw an exception, this method throws an |
2288 |
* (unchecked) {@link CompletionException} with the underlying |
2289 |
* exception as its cause. |
2290 |
* |
2291 |
* @return the result value |
2292 |
* @throws CancellationException if the computation was cancelled |
2293 |
* @throws CompletionException if this future completed |
2294 |
* exceptionally or a completion computation threw an exception |
2295 |
*/ |
2296 |
public T join() { |
2297 |
Object r; Throwable ex; |
2298 |
if ((r = result) == null) |
2299 |
r = waitingGet(false); |
2300 |
if (!(r instanceof AltResult)) { |
2301 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2302 |
return tr; |
2303 |
} |
2304 |
if ((ex = ((AltResult)r).ex) == null) |
2305 |
return null; |
2306 |
if (ex instanceof CancellationException) |
2307 |
throw (CancellationException)ex; |
2308 |
if (ex instanceof CompletionException) |
2309 |
throw (CompletionException)ex; |
2310 |
throw new CompletionException(ex); |
2311 |
} |
2312 |
|
2313 |
/** |
2314 |
* Returns the result value (or throws any encountered exception) |
2315 |
* if completed, else returns the given valueIfAbsent. |
2316 |
* |
2317 |
* @param valueIfAbsent the value to return if not completed |
2318 |
* @return the result value, if completed, else the given valueIfAbsent |
2319 |
* @throws CancellationException if the computation was cancelled |
2320 |
* @throws CompletionException if this future completed |
2321 |
* exceptionally or a completion computation threw an exception |
2322 |
*/ |
2323 |
public T getNow(T valueIfAbsent) { |
2324 |
Object r; Throwable ex; |
2325 |
if ((r = result) == null) |
2326 |
return valueIfAbsent; |
2327 |
if (!(r instanceof AltResult)) { |
2328 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2329 |
return tr; |
2330 |
} |
2331 |
if ((ex = ((AltResult)r).ex) == null) |
2332 |
return null; |
2333 |
if (ex instanceof CancellationException) |
2334 |
throw (CancellationException)ex; |
2335 |
if (ex instanceof CompletionException) |
2336 |
throw (CompletionException)ex; |
2337 |
throw new CompletionException(ex); |
2338 |
} |
2339 |
|
2340 |
/** |
2341 |
* If not already completed, sets the value returned by {@link |
2342 |
* #get()} and related methods to the given value. |
2343 |
* |
2344 |
* @param value the result value |
2345 |
* @return {@code true} if this invocation caused this CompletableFuture |
2346 |
* to transition to a completed state, else {@code false} |
2347 |
*/ |
2348 |
public boolean complete(T value) { |
2349 |
boolean triggered = result == null && |
2350 |
UNSAFE.compareAndSwapObject(this, RESULT, null, |
2351 |
value == null ? NIL : value); |
2352 |
postComplete(this); |
2353 |
return triggered; |
2354 |
} |
2355 |
|
2356 |
/** |
2357 |
* If not already completed, causes invocations of {@link #get()} |
2358 |
* and related methods to throw the given exception. |
2359 |
* |
2360 |
* @param ex the exception |
2361 |
* @return {@code true} if this invocation caused this CompletableFuture |
2362 |
* to transition to a completed state, else {@code false} |
2363 |
*/ |
2364 |
public boolean completeExceptionally(Throwable ex) { |
2365 |
if (ex == null) throw new NullPointerException(); |
2366 |
boolean triggered = result == null && |
2367 |
UNSAFE.compareAndSwapObject(this, RESULT, null, new AltResult(ex)); |
2368 |
postComplete(this); |
2369 |
return triggered; |
2370 |
} |
2371 |
|
2372 |
// CompletionStage methods |
2373 |
|
2374 |
public <U> CompletableFuture<U> thenApply |
2375 |
(Function<? super T,? extends U> fn) { |
2376 |
return doThenApply(fn, null); |
2377 |
} |
2378 |
|
2379 |
public <U> CompletableFuture<U> thenApplyAsync |
2380 |
(Function<? super T,? extends U> fn) { |
2381 |
return doThenApply(fn, ForkJoinPool.commonPool()); |
2382 |
} |
2383 |
|
2384 |
public <U> CompletableFuture<U> thenApplyAsync |
2385 |
(Function<? super T,? extends U> fn, |
2386 |
Executor executor) { |
2387 |
if (executor == null) throw new NullPointerException(); |
2388 |
return doThenApply(fn, executor); |
2389 |
} |
2390 |
|
2391 |
public CompletableFuture<Void> thenAccept |
2392 |
(Consumer<? super T> action) { |
2393 |
return doThenAccept(action, null); |
2394 |
} |
2395 |
|
2396 |
public CompletableFuture<Void> thenAcceptAsync |
2397 |
(Consumer<? super T> action) { |
2398 |
return doThenAccept(action, ForkJoinPool.commonPool()); |
2399 |
} |
2400 |
|
2401 |
public CompletableFuture<Void> thenAcceptAsync |
2402 |
(Consumer<? super T> action, |
2403 |
Executor executor) { |
2404 |
if (executor == null) throw new NullPointerException(); |
2405 |
return doThenAccept(action, executor); |
2406 |
} |
2407 |
|
2408 |
public CompletableFuture<Void> thenRun |
2409 |
(Runnable action) { |
2410 |
return doThenRun(action, null); |
2411 |
} |
2412 |
|
2413 |
public CompletableFuture<Void> thenRunAsync |
2414 |
(Runnable action) { |
2415 |
return doThenRun(action, ForkJoinPool.commonPool()); |
2416 |
} |
2417 |
|
2418 |
public CompletableFuture<Void> thenRunAsync |
2419 |
(Runnable action, |
2420 |
Executor executor) { |
2421 |
if (executor == null) throw new NullPointerException(); |
2422 |
return doThenRun(action, executor); |
2423 |
} |
2424 |
|
2425 |
public <U,V> CompletableFuture<V> thenCombine |
2426 |
(CompletionStage<? extends U> other, |
2427 |
BiFunction<? super T,? super U,? extends V> fn) { |
2428 |
return doThenCombine(other.toCompletableFuture(), fn, null); |
2429 |
} |
2430 |
|
2431 |
public <U,V> CompletableFuture<V> thenCombineAsync |
2432 |
(CompletionStage<? extends U> other, |
2433 |
BiFunction<? super T,? super U,? extends V> fn) { |
2434 |
return doThenCombine(other.toCompletableFuture(), fn, |
2435 |
ForkJoinPool.commonPool()); |
2436 |
} |
2437 |
|
2438 |
public <U,V> CompletableFuture<V> thenCombineAsync |
2439 |
(CompletionStage<? extends U> other, |
2440 |
BiFunction<? super T,? super U,? extends V> fn, |
2441 |
Executor executor) { |
2442 |
if (executor == null) throw new NullPointerException(); |
2443 |
return doThenCombine(other.toCompletableFuture(), fn, executor); |
2444 |
} |
2445 |
|
2446 |
public <U> CompletableFuture<Void> thenAcceptBoth |
2447 |
(CompletionStage<? extends U> other, |
2448 |
BiConsumer<? super T, ? super U> action) { |
2449 |
return doThenAcceptBoth(other.toCompletableFuture(), action, null); |
2450 |
} |
2451 |
|
2452 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2453 |
(CompletionStage<? extends U> other, |
2454 |
BiConsumer<? super T, ? super U> action) { |
2455 |
return doThenAcceptBoth(other.toCompletableFuture(), action, |
2456 |
ForkJoinPool.commonPool()); |
2457 |
} |
2458 |
|
2459 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2460 |
(CompletionStage<? extends U> other, |
2461 |
BiConsumer<? super T, ? super U> action, |
2462 |
Executor executor) { |
2463 |
if (executor == null) throw new NullPointerException(); |
2464 |
return doThenAcceptBoth(other.toCompletableFuture(), action, executor); |
2465 |
} |
2466 |
|
2467 |
public CompletableFuture<Void> runAfterBoth |
2468 |
(CompletionStage<?> other, |
2469 |
Runnable action) { |
2470 |
return doRunAfterBoth(other.toCompletableFuture(), action, null); |
2471 |
} |
2472 |
|
2473 |
public CompletableFuture<Void> runAfterBothAsync |
2474 |
(CompletionStage<?> other, |
2475 |
Runnable action) { |
2476 |
return doRunAfterBoth(other.toCompletableFuture(), action, |
2477 |
ForkJoinPool.commonPool()); |
2478 |
} |
2479 |
|
2480 |
public CompletableFuture<Void> runAfterBothAsync |
2481 |
(CompletionStage<?> other, |
2482 |
Runnable action, |
2483 |
Executor executor) { |
2484 |
if (executor == null) throw new NullPointerException(); |
2485 |
return doRunAfterBoth(other.toCompletableFuture(), action, executor); |
2486 |
} |
2487 |
|
2488 |
|
2489 |
public <U> CompletableFuture<U> applyToEither |
2490 |
(CompletionStage<? extends T> other, |
2491 |
Function<? super T, U> fn) { |
2492 |
return doApplyToEither(other.toCompletableFuture(), fn, null); |
2493 |
} |
2494 |
|
2495 |
public <U> CompletableFuture<U> applyToEitherAsync |
2496 |
(CompletionStage<? extends T> other, |
2497 |
Function<? super T, U> fn) { |
2498 |
return doApplyToEither(other.toCompletableFuture(), fn, |
2499 |
ForkJoinPool.commonPool()); |
2500 |
} |
2501 |
|
2502 |
public <U> CompletableFuture<U> applyToEitherAsync |
2503 |
(CompletionStage<? extends T> other, |
2504 |
Function<? super T, U> fn, |
2505 |
Executor executor) { |
2506 |
if (executor == null) throw new NullPointerException(); |
2507 |
return doApplyToEither(other.toCompletableFuture(), fn, executor); |
2508 |
} |
2509 |
|
2510 |
public CompletableFuture<Void> acceptEither |
2511 |
(CompletionStage<? extends T> other, |
2512 |
Consumer<? super T> action) { |
2513 |
return doAcceptEither(other.toCompletableFuture(), action, null); |
2514 |
} |
2515 |
|
2516 |
public CompletableFuture<Void> acceptEitherAsync |
2517 |
(CompletionStage<? extends T> other, |
2518 |
Consumer<? super T> action) { |
2519 |
return doAcceptEither(other.toCompletableFuture(), action, |
2520 |
ForkJoinPool.commonPool()); |
2521 |
} |
2522 |
|
2523 |
public CompletableFuture<Void> acceptEitherAsync |
2524 |
(CompletionStage<? extends T> other, |
2525 |
Consumer<? super T> action, |
2526 |
Executor executor) { |
2527 |
if (executor == null) throw new NullPointerException(); |
2528 |
return doAcceptEither(other.toCompletableFuture(), action, executor); |
2529 |
} |
2530 |
|
2531 |
public CompletableFuture<Void> runAfterEither(CompletionStage<?> other, |
2532 |
Runnable action) { |
2533 |
return doRunAfterEither(other.toCompletableFuture(), action, null); |
2534 |
} |
2535 |
|
2536 |
public CompletableFuture<Void> runAfterEitherAsync |
2537 |
(CompletionStage<?> other, |
2538 |
Runnable action) { |
2539 |
return doRunAfterEither(other.toCompletableFuture(), action, |
2540 |
ForkJoinPool.commonPool()); |
2541 |
} |
2542 |
|
2543 |
public CompletableFuture<Void> runAfterEitherAsync |
2544 |
(CompletionStage<?> other, |
2545 |
Runnable action, |
2546 |
Executor executor) { |
2547 |
if (executor == null) throw new NullPointerException(); |
2548 |
return doRunAfterEither(other.toCompletableFuture(), action, executor); |
2549 |
} |
2550 |
|
2551 |
public <U> CompletableFuture<U> thenCompose |
2552 |
(Function<? super T, ? extends CompletionStage<U>> fn) { |
2553 |
return doThenCompose(fn, null); |
2554 |
} |
2555 |
|
2556 |
public <U> CompletableFuture<U> thenComposeAsync |
2557 |
(Function<? super T, ? extends CompletionStage<U>> fn) { |
2558 |
return doThenCompose(fn, ForkJoinPool.commonPool()); |
2559 |
} |
2560 |
|
2561 |
public <U> CompletableFuture<U> thenComposeAsync |
2562 |
(Function<? super T, ? extends CompletionStage<U>> fn, |
2563 |
Executor executor) { |
2564 |
if (executor == null) throw new NullPointerException(); |
2565 |
return doThenCompose(fn, executor); |
2566 |
} |
2567 |
|
2568 |
public CompletableFuture<T> whenComplete |
2569 |
(BiConsumer<? super T, ? super Throwable> action) { |
2570 |
return doWhenComplete(action, null); |
2571 |
} |
2572 |
|
2573 |
public CompletableFuture<T> whenCompleteAsync |
2574 |
(BiConsumer<? super T, ? super Throwable> action) { |
2575 |
return doWhenComplete(action, ForkJoinPool.commonPool()); |
2576 |
} |
2577 |
|
2578 |
public CompletableFuture<T> whenCompleteAsync |
2579 |
(BiConsumer<? super T, ? super Throwable> action, |
2580 |
Executor executor) { |
2581 |
if (executor == null) throw new NullPointerException(); |
2582 |
return doWhenComplete(action, executor); |
2583 |
} |
2584 |
|
2585 |
public <U> CompletableFuture<U> handle |
2586 |
(BiFunction<? super T, Throwable, ? extends U> fn) { |
2587 |
return doHandle(fn, null); |
2588 |
} |
2589 |
|
2590 |
public <U> CompletableFuture<U> handleAsync |
2591 |
(BiFunction<? super T, Throwable, ? extends U> fn) { |
2592 |
return doHandle(fn, ForkJoinPool.commonPool()); |
2593 |
} |
2594 |
|
2595 |
public <U> CompletableFuture<U> handleAsync |
2596 |
(BiFunction<? super T, Throwable, ? extends U> fn, |
2597 |
Executor executor) { |
2598 |
if (executor == null) throw new NullPointerException(); |
2599 |
return doHandle(fn, executor); |
2600 |
} |
2601 |
|
2602 |
/** |
2603 |
* Returns this CompletableFuture |
2604 |
* |
2605 |
* @return this CompletableFuture |
2606 |
*/ |
2607 |
public CompletableFuture<T> toCompletableFuture() { |
2608 |
return this; |
2609 |
} |
2610 |
|
2611 |
// not in interface CompletionStage |
2612 |
|
2613 |
/** |
2614 |
* Returns a new CompletableFuture that is completed when this |
2615 |
* CompletableFuture completes, with the result of the given |
2616 |
* function of the exception triggering this CompletableFuture's |
2617 |
* completion when it completes exceptionally; otherwise, if this |
2618 |
* CompletableFuture completes normally, then the returned |
2619 |
* CompletableFuture also completes normally with the same value. |
2620 |
* Note: More flexible versions of this functionality are |
2621 |
* available using methods {@code whenComplete} and {@code handle}. |
2622 |
* |
2623 |
* @param fn the function to use to compute the value of the |
2624 |
* returned CompletableFuture if this CompletableFuture completed |
2625 |
* exceptionally |
2626 |
* @return the new CompletableFuture |
2627 |
*/ |
2628 |
public CompletableFuture<T> exceptionally |
2629 |
(Function<Throwable, ? extends T> fn) { |
2630 |
if (fn == null) throw new NullPointerException(); |
2631 |
CompletableFuture<T> dst = new CompletableFuture<T>(); |
2632 |
Object r; |
2633 |
if ((r = result) == null) { |
2634 |
ExceptionCompletion<T> d = |
2635 |
new ExceptionCompletion<T>(this, fn, dst); |
2636 |
CompletionNode p = new CompletionNode(d); |
2637 |
while (result == null) { |
2638 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2639 |
p.next = completions, p)) |
2640 |
break; |
2641 |
} |
2642 |
d.tryComplete(); |
2643 |
} |
2644 |
else { |
2645 |
T t = null; Throwable ex, dx = null; |
2646 |
if (r instanceof AltResult) { |
2647 |
if ((ex = ((AltResult)r).ex) != null) { |
2648 |
try { |
2649 |
t = fn.apply(ex); |
2650 |
} catch (Throwable rex) { |
2651 |
dx = rex; |
2652 |
} |
2653 |
} |
2654 |
} |
2655 |
else { |
2656 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2657 |
t = tr; |
2658 |
} |
2659 |
dst.internalComplete(t, dx); |
2660 |
} |
2661 |
return dst; |
2662 |
} |
2663 |
|
2664 |
/* ------------- Arbitrary-arity constructions -------------- */ |
2665 |
|
2666 |
/* |
2667 |
* The basic plan of attack is to recursively form binary |
2668 |
* completion trees of elements. This can be overkill for small |
2669 |
* sets, but scales nicely. The And/All vs Or/Any forms use the |
2670 |
* same idea, but details differ. |
2671 |
*/ |
2672 |
|
2673 |
/** |
2674 |
* Returns a new CompletableFuture that is completed when all of |
2675 |
* the given CompletableFutures complete. If any of the given |
2676 |
* CompletableFutures complete exceptionally, then the returned |
2677 |
* CompletableFuture also does so, with a CompletionException |
2678 |
* holding this exception as its cause. Otherwise, the results, |
2679 |
* if any, of the given CompletableFutures are not reflected in |
2680 |
* the returned CompletableFuture, but may be obtained by |
2681 |
* inspecting them individually. If no CompletableFutures are |
2682 |
* provided, returns a CompletableFuture completed with the value |
2683 |
* {@code null}. |
2684 |
* |
2685 |
* <p>Among the applications of this method is to await completion |
2686 |
* of a set of independent CompletableFutures before continuing a |
2687 |
* program, as in: {@code CompletableFuture.allOf(c1, c2, |
2688 |
* c3).join();}. |
2689 |
* |
2690 |
* @param cfs the CompletableFutures |
2691 |
* @return a new CompletableFuture that is completed when all of the |
2692 |
* given CompletableFutures complete |
2693 |
* @throws NullPointerException if the array or any of its elements are |
2694 |
* {@code null} |
2695 |
*/ |
2696 |
public static CompletableFuture<Void> allOf(CompletableFuture<?>... cfs) { |
2697 |
int len = cfs.length; // Directly handle empty and singleton cases |
2698 |
if (len > 1) |
2699 |
return allTree(cfs, 0, len - 1); |
2700 |
else { |
2701 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2702 |
CompletableFuture<?> f; |
2703 |
if (len == 0) |
2704 |
dst.result = NIL; |
2705 |
else if ((f = cfs[0]) == null) |
2706 |
throw new NullPointerException(); |
2707 |
else { |
2708 |
ThenPropagate d = null; |
2709 |
CompletionNode p = null; |
2710 |
Object r; |
2711 |
while ((r = f.result) == null) { |
2712 |
if (d == null) |
2713 |
d = new ThenPropagate(f, dst); |
2714 |
else if (p == null) |
2715 |
p = new CompletionNode(d); |
2716 |
else if (UNSAFE.compareAndSwapObject |
2717 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2718 |
break; |
2719 |
} |
2720 |
if (d != null) |
2721 |
d.tryComplete(); |
2722 |
else |
2723 |
dst.internalComplete(null, (r instanceof AltResult) ? |
2724 |
((AltResult)r).ex : null); |
2725 |
} |
2726 |
return dst; |
2727 |
} |
2728 |
} |
2729 |
|
2730 |
/** |
2731 |
* Recursively constructs an And'ed tree of CompletableFutures. |
2732 |
* Called only when array known to have at least two elements. |
2733 |
*/ |
2734 |
private static CompletableFuture<Void> allTree(CompletableFuture<?>[] cfs, |
2735 |
int lo, int hi) { |
2736 |
CompletableFuture<?> fst, snd; |
2737 |
int mid = (lo + hi) >>> 1; |
2738 |
if ((fst = (lo == mid ? cfs[lo] : allTree(cfs, lo, mid))) == null || |
2739 |
(snd = (hi == mid+1 ? cfs[hi] : allTree(cfs, mid+1, hi))) == null) |
2740 |
throw new NullPointerException(); |
2741 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2742 |
AndCompletion d = null; |
2743 |
CompletionNode p = null, q = null; |
2744 |
Object r = null, s = null; |
2745 |
while ((r = fst.result) == null || (s = snd.result) == null) { |
2746 |
if (d == null) |
2747 |
d = new AndCompletion(fst, snd, dst); |
2748 |
else if (p == null) |
2749 |
p = new CompletionNode(d); |
2750 |
else if (q == null) { |
2751 |
if (UNSAFE.compareAndSwapObject |
2752 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
2753 |
q = new CompletionNode(d); |
2754 |
} |
2755 |
else if (UNSAFE.compareAndSwapObject |
2756 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
2757 |
break; |
2758 |
} |
2759 |
if (d != null) |
2760 |
d.tryComplete(); |
2761 |
else { |
2762 |
Throwable ex; |
2763 |
if (r instanceof AltResult) |
2764 |
ex = ((AltResult)r).ex; |
2765 |
else |
2766 |
ex = null; |
2767 |
if (ex == null && (s instanceof AltResult)) |
2768 |
ex = ((AltResult)s).ex; |
2769 |
dst.internalComplete(null, ex); |
2770 |
} |
2771 |
return dst; |
2772 |
} |
2773 |
|
2774 |
/** |
2775 |
* Returns a new CompletableFuture that is completed when any of |
2776 |
* the given CompletableFutures complete, with the same result. |
2777 |
* Otherwise, if it completed exceptionally, the returned |
2778 |
* CompletableFuture also does so, with a CompletionException |
2779 |
* holding this exception as its cause. If no CompletableFutures |
2780 |
* are provided, returns an incomplete CompletableFuture. |
2781 |
* |
2782 |
* @param cfs the CompletableFutures |
2783 |
* @return a new CompletableFuture that is completed with the |
2784 |
* result or exception of any of the given CompletableFutures when |
2785 |
* one completes |
2786 |
* @throws NullPointerException if the array or any of its elements are |
2787 |
* {@code null} |
2788 |
*/ |
2789 |
public static CompletableFuture<Object> anyOf(CompletableFuture<?>... cfs) { |
2790 |
int len = cfs.length; // Same idea as allOf |
2791 |
if (len > 1) |
2792 |
return anyTree(cfs, 0, len - 1); |
2793 |
else { |
2794 |
CompletableFuture<Object> dst = new CompletableFuture<Object>(); |
2795 |
CompletableFuture<?> f; |
2796 |
if (len == 0) |
2797 |
; // skip |
2798 |
else if ((f = cfs[0]) == null) |
2799 |
throw new NullPointerException(); |
2800 |
else { |
2801 |
ThenCopy<Object> d = null; |
2802 |
CompletionNode p = null; |
2803 |
Object r; |
2804 |
while ((r = f.result) == null) { |
2805 |
if (d == null) |
2806 |
d = new ThenCopy<Object>(f, dst); |
2807 |
else if (p == null) |
2808 |
p = new CompletionNode(d); |
2809 |
else if (UNSAFE.compareAndSwapObject |
2810 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2811 |
break; |
2812 |
} |
2813 |
if (d != null) |
2814 |
d.tryComplete(); |
2815 |
else { |
2816 |
Throwable ex; Object t; |
2817 |
if (r instanceof AltResult) { |
2818 |
ex = ((AltResult)r).ex; |
2819 |
t = null; |
2820 |
} |
2821 |
else { |
2822 |
ex = null; |
2823 |
t = r; |
2824 |
} |
2825 |
dst.internalComplete(t, ex); |
2826 |
} |
2827 |
} |
2828 |
return dst; |
2829 |
} |
2830 |
} |
2831 |
|
2832 |
/** |
2833 |
* Recursively constructs an Or'ed tree of CompletableFutures. |
2834 |
*/ |
2835 |
private static CompletableFuture<Object> anyTree(CompletableFuture<?>[] cfs, |
2836 |
int lo, int hi) { |
2837 |
CompletableFuture<?> fst, snd; |
2838 |
int mid = (lo + hi) >>> 1; |
2839 |
if ((fst = (lo == mid ? cfs[lo] : anyTree(cfs, lo, mid))) == null || |
2840 |
(snd = (hi == mid+1 ? cfs[hi] : anyTree(cfs, mid+1, hi))) == null) |
2841 |
throw new NullPointerException(); |
2842 |
CompletableFuture<Object> dst = new CompletableFuture<Object>(); |
2843 |
OrCompletion d = null; |
2844 |
CompletionNode p = null, q = null; |
2845 |
Object r; |
2846 |
while ((r = fst.result) == null && (r = snd.result) == null) { |
2847 |
if (d == null) |
2848 |
d = new OrCompletion(fst, snd, dst); |
2849 |
else if (p == null) |
2850 |
p = new CompletionNode(d); |
2851 |
else if (q == null) { |
2852 |
if (UNSAFE.compareAndSwapObject |
2853 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
2854 |
q = new CompletionNode(d); |
2855 |
} |
2856 |
else if (UNSAFE.compareAndSwapObject |
2857 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
2858 |
break; |
2859 |
} |
2860 |
if (d != null) |
2861 |
d.tryComplete(); |
2862 |
else { |
2863 |
Throwable ex; Object t; |
2864 |
if (r instanceof AltResult) { |
2865 |
ex = ((AltResult)r).ex; |
2866 |
t = null; |
2867 |
} |
2868 |
else { |
2869 |
ex = null; |
2870 |
t = r; |
2871 |
} |
2872 |
dst.internalComplete(t, ex); |
2873 |
} |
2874 |
return dst; |
2875 |
} |
2876 |
|
2877 |
/* ------------- Control and status methods -------------- */ |
2878 |
|
2879 |
/** |
2880 |
* If not already completed, completes this CompletableFuture with |
2881 |
* a {@link CancellationException}. Dependent CompletableFutures |
2882 |
* that have not already completed will also complete |
2883 |
* exceptionally, with a {@link CompletionException} caused by |
2884 |
* this {@code CancellationException}. |
2885 |
* |
2886 |
* @param mayInterruptIfRunning this value has no effect in this |
2887 |
* implementation because interrupts are not used to control |
2888 |
* processing. |
2889 |
* |
2890 |
* @return {@code true} if this task is now cancelled |
2891 |
*/ |
2892 |
public boolean cancel(boolean mayInterruptIfRunning) { |
2893 |
boolean cancelled = (result == null) && |
2894 |
UNSAFE.compareAndSwapObject |
2895 |
(this, RESULT, null, new AltResult(new CancellationException())); |
2896 |
postComplete(this); |
2897 |
return cancelled || isCancelled(); |
2898 |
} |
2899 |
|
2900 |
/** |
2901 |
* Returns {@code true} if this CompletableFuture was cancelled |
2902 |
* before it completed normally. |
2903 |
* |
2904 |
* @return {@code true} if this CompletableFuture was cancelled |
2905 |
* before it completed normally |
2906 |
*/ |
2907 |
public boolean isCancelled() { |
2908 |
Object r; |
2909 |
return ((r = result) instanceof AltResult) && |
2910 |
(((AltResult)r).ex instanceof CancellationException); |
2911 |
} |
2912 |
|
2913 |
/** |
2914 |
* Returns {@code true} if this CompletableFuture completed |
2915 |
* exceptionally, in any way. Possible causes include |
2916 |
* cancellation, explicit invocation of {@code |
2917 |
* completeExceptionally}, and abrupt termination of a |
2918 |
* CompletionStage action. |
2919 |
* |
2920 |
* @return {@code true} if this CompletableFuture completed |
2921 |
* exceptionally |
2922 |
*/ |
2923 |
public boolean isCompletedExceptionally() { |
2924 |
Object r; |
2925 |
return ((r = result) instanceof AltResult) && r != NIL; |
2926 |
} |
2927 |
|
2928 |
/** |
2929 |
* Forcibly sets or resets the value subsequently returned by |
2930 |
* method {@link #get()} and related methods, whether or not |
2931 |
* already completed. This method is designed for use only in |
2932 |
* error recovery actions, and even in such situations may result |
2933 |
* in ongoing dependent completions using established versus |
2934 |
* overwritten outcomes. |
2935 |
* |
2936 |
* @param value the completion value |
2937 |
*/ |
2938 |
public void obtrudeValue(T value) { |
2939 |
result = (value == null) ? NIL : value; |
2940 |
postComplete(this); |
2941 |
} |
2942 |
|
2943 |
/** |
2944 |
* Forcibly causes subsequent invocations of method {@link #get()} |
2945 |
* and related methods to throw the given exception, whether or |
2946 |
* not already completed. This method is designed for use only in |
2947 |
* recovery actions, and even in such situations may result in |
2948 |
* ongoing dependent completions using established versus |
2949 |
* overwritten outcomes. |
2950 |
* |
2951 |
* @param ex the exception |
2952 |
*/ |
2953 |
public void obtrudeException(Throwable ex) { |
2954 |
if (ex == null) throw new NullPointerException(); |
2955 |
result = new AltResult(ex); |
2956 |
postComplete(this); |
2957 |
} |
2958 |
|
2959 |
/** |
2960 |
* Returns the estimated number of CompletableFutures whose |
2961 |
* completions are awaiting completion of this CompletableFuture. |
2962 |
* This method is designed for use in monitoring system state, not |
2963 |
* for synchronization control. |
2964 |
* |
2965 |
* @return the number of dependent CompletableFutures |
2966 |
*/ |
2967 |
public int getNumberOfDependents() { |
2968 |
int count = 0; |
2969 |
for (CompletionNode p = completions; p != null; p = p.next) |
2970 |
++count; |
2971 |
return count; |
2972 |
} |
2973 |
|
2974 |
/** |
2975 |
* Returns a string identifying this CompletableFuture, as well as |
2976 |
* its completion state. The state, in brackets, contains the |
2977 |
* String {@code "Completed Normally"} or the String {@code |
2978 |
* "Completed Exceptionally"}, or the String {@code "Not |
2979 |
* completed"} followed by the number of CompletableFutures |
2980 |
* dependent upon its completion, if any. |
2981 |
* |
2982 |
* @return a string identifying this CompletableFuture, as well as its state |
2983 |
*/ |
2984 |
public String toString() { |
2985 |
Object r = result; |
2986 |
int count; |
2987 |
return super.toString() + |
2988 |
((r == null) ? |
2989 |
(((count = getNumberOfDependents()) == 0) ? |
2990 |
"[Not completed]" : |
2991 |
"[Not completed, " + count + " dependents]") : |
2992 |
(((r instanceof AltResult) && ((AltResult)r).ex != null) ? |
2993 |
"[Completed exceptionally]" : |
2994 |
"[Completed normally]")); |
2995 |
} |
2996 |
|
2997 |
// Unsafe mechanics |
2998 |
private static final sun.misc.Unsafe UNSAFE; |
2999 |
private static final long RESULT; |
3000 |
private static final long WAITERS; |
3001 |
private static final long COMPLETIONS; |
3002 |
static { |
3003 |
try { |
3004 |
UNSAFE = sun.misc.Unsafe.getUnsafe(); |
3005 |
Class<?> k = CompletableFuture.class; |
3006 |
RESULT = UNSAFE.objectFieldOffset |
3007 |
(k.getDeclaredField("result")); |
3008 |
WAITERS = UNSAFE.objectFieldOffset |
3009 |
(k.getDeclaredField("waiters")); |
3010 |
COMPLETIONS = UNSAFE.objectFieldOffset |
3011 |
(k.getDeclaredField("completions")); |
3012 |
} catch (Exception e) { |
3013 |
throw new Error(e); |
3014 |
} |
3015 |
} |
3016 |
} |