public class CompletableFuture<T> extends Object implements Future<T>, CompletionStage<T>
Future
that may be explicitly completed (setting its
value and status), and may be used as a CompletionStage
,
supporting dependent functions and actions that trigger upon its
completion.
When two or more threads attempt to
complete
,
completeExceptionally
, or
cancel
a CompletableFuture, only one of them succeeds.
In addition to these and related methods for directly
manipulating status and results, CompletableFuture implements
interface CompletionStage
with the following policies:
ForkJoinPool.commonPool()
(unless it does not support a parallelism level of at least two, in
which case, a new Thread is created to run each task). To simplify
monitoring, debugging, and tracking, all generated asynchronous
tasks are instances of the marker interface CompletableFuture.AsynchronousCompletionTask
. CompletableFuture also implements Future
with the following
policies:
FutureTask
) this class has no direct
control over the computation that causes it to be completed,
cancellation is treated as just another form of exceptional
completion. Method cancel
has the same effect as
completeExceptionally(new CancellationException())
. Method
isCompletedExceptionally()
can be used to determine if a
CompletableFuture completed in any exceptional fashion.get()
and get(long, TimeUnit)
throw an
ExecutionException
with the same cause as held in the
corresponding CompletionException. To simplify usage in most
contexts, this class also defines methods join()
and
getNow(T)
that instead throw the CompletionException directly
in these cases.Modifier and Type | Class and Description |
---|---|
static interface |
CompletableFuture.AsynchronousCompletionTask
A marker interface identifying asynchronous tasks produced by
async methods. |
Constructor and Description |
---|
CompletableFuture()
Creates a new incomplete CompletableFuture.
|
Modifier and Type | Method and Description |
---|---|
CompletableFuture<Void> |
acceptEither(CompletionStage<? extends T> other,
Consumer<? super T> action)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, is executed with the
corresponding result as argument to the supplied action.
|
CompletableFuture<Void> |
acceptEitherAsync(CompletionStage<? extends T> other,
Consumer<? super T> action)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, is executed using this
stage's default asynchronous execution facility, with the
corresponding result as argument to the supplied action.
|
CompletableFuture<Void> |
acceptEitherAsync(CompletionStage<? extends T> other,
Consumer<? super T> action,
Executor executor)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, is executed using the
supplied executor, with the corresponding result as argument to
the supplied function.
|
static CompletableFuture<Void> |
allOf(CompletableFuture<?>... cfs)
Returns a new CompletableFuture that is completed when all of
the given CompletableFutures complete.
|
static CompletableFuture<Object> |
anyOf(CompletableFuture<?>... cfs)
Returns a new CompletableFuture that is completed when any of
the given CompletableFutures complete, with the same result.
|
<U> CompletableFuture<U> |
applyToEither(CompletionStage<? extends T> other,
Function<? super T,U> fn)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, is executed with the
corresponding result as argument to the supplied function.
|
<U> CompletableFuture<U> |
applyToEitherAsync(CompletionStage<? extends T> other,
Function<? super T,U> fn)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, is executed using this
stage's default asynchronous execution facility, with the
corresponding result as argument to the supplied function.
|
<U> CompletableFuture<U> |
applyToEitherAsync(CompletionStage<? extends T> other,
Function<? super T,U> fn,
Executor executor)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, is executed using the
supplied executor, with the corresponding result as argument to
the supplied function.
|
boolean |
cancel(boolean mayInterruptIfRunning)
If not already completed, completes this CompletableFuture with
a
CancellationException . |
boolean |
complete(T value)
If not already completed, sets the value returned by
get() and related methods to the given value. |
static <U> CompletableFuture<U> |
completedFuture(U value)
Returns a new CompletableFuture that is already completed with
the given value.
|
boolean |
completeExceptionally(Throwable ex)
If not already completed, causes invocations of
get()
and related methods to throw the given exception. |
CompletableFuture<T> |
exceptionally(Function<Throwable,? extends T> fn)
Returns a new CompletableFuture that is completed when this
CompletableFuture completes, with the result of the given
function of the exception triggering this CompletableFuture's
completion when it completes exceptionally; otherwise, if this
CompletableFuture completes normally, then the returned
CompletableFuture also completes normally with the same value.
|
T |
get()
Waits if necessary for this future to complete, and then
returns its result.
|
T |
get(long timeout,
TimeUnit unit)
Waits if necessary for at most the given time for this future
to complete, and then returns its result, if available.
|
T |
getNow(T valueIfAbsent)
Returns the result value (or throws any encountered exception)
if completed, else returns the given valueIfAbsent.
|
int |
getNumberOfDependents()
Returns the estimated number of CompletableFutures whose
completions are awaiting completion of this CompletableFuture.
|
<U> CompletableFuture<U> |
handle(BiFunction<? super T,Throwable,? extends U> fn)
Returns a new CompletionStage that, when this stage completes
either normally or exceptionally, is executed with this stage's
result and exception as arguments to the supplied function.
|
<U> CompletableFuture<U> |
handleAsync(BiFunction<? super T,Throwable,? extends U> fn)
Returns a new CompletionStage that, when this stage completes
either normally or exceptionally, is executed using this stage's
default asynchronous execution facility, with this stage's
result and exception as arguments to the supplied function.
|
<U> CompletableFuture<U> |
handleAsync(BiFunction<? super T,Throwable,? extends U> fn,
Executor executor)
Returns a new CompletionStage that, when this stage completes
either normally or exceptionally, is executed using the
supplied executor, with this stage's result and exception as
arguments to the supplied function.
|
boolean |
isCancelled()
Returns
true if this CompletableFuture was cancelled
before it completed normally. |
boolean |
isCompletedExceptionally()
Returns
true if this CompletableFuture completed
exceptionally, in any way. |
boolean |
isDone()
Returns
true if completed in any fashion: normally,
exceptionally, or via cancellation. |
T |
join()
Returns the result value when complete, or throws an
(unchecked) exception if completed exceptionally.
|
void |
obtrudeException(Throwable ex)
Forcibly causes subsequent invocations of method
get()
and related methods to throw the given exception, whether or
not already completed. |
void |
obtrudeValue(T value)
Forcibly sets or resets the value subsequently returned by
method
get() and related methods, whether or not
already completed. |
CompletableFuture<Void> |
runAfterBoth(CompletionStage<?> other,
Runnable action)
Returns a new CompletionStage that, when this and the other
given stage both complete normally, executes the given action.
|
CompletableFuture<Void> |
runAfterBothAsync(CompletionStage<?> other,
Runnable action)
Returns a new CompletionStage that, when this and the other
given stage complete normally, executes the given action using
this stage's default asynchronous execution facility.
|
CompletableFuture<Void> |
runAfterBothAsync(CompletionStage<?> other,
Runnable action,
Executor executor)
Returns a new CompletionStage that, when this and the other
given stage complete normally, executes the given action using
the supplied executor.
|
CompletableFuture<Void> |
runAfterEither(CompletionStage<?> other,
Runnable action)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, executes the given action.
|
CompletableFuture<Void> |
runAfterEitherAsync(CompletionStage<?> other,
Runnable action)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, executes the given action
using this stage's default asynchronous execution facility.
|
CompletableFuture<Void> |
runAfterEitherAsync(CompletionStage<?> other,
Runnable action,
Executor executor)
Returns a new CompletionStage that, when either this or the
other given stage complete normally, executes the given action
using the supplied executor.
|
static CompletableFuture<Void> |
runAsync(Runnable runnable)
Returns a new CompletableFuture that is asynchronously completed
by a task running in the
ForkJoinPool.commonPool() after
it runs the given action. |
static CompletableFuture<Void> |
runAsync(Runnable runnable,
Executor executor)
Returns a new CompletableFuture that is asynchronously completed
by a task running in the given executor after it runs the given
action.
|
static <U> CompletableFuture<U> |
supplyAsync(Supplier<U> supplier)
Returns a new CompletableFuture that is asynchronously completed
by a task running in the
ForkJoinPool.commonPool() with
the value obtained by calling the given Supplier. |
static <U> CompletableFuture<U> |
supplyAsync(Supplier<U> supplier,
Executor executor)
Returns a new CompletableFuture that is asynchronously completed
by a task running in the given executor with the value obtained
by calling the given Supplier.
|
CompletableFuture<Void> |
thenAccept(Consumer<? super T> action)
Returns a new CompletionStage that, when this stage completes
normally, is executed with this stage's result as the argument
to the supplied action.
|
CompletableFuture<Void> |
thenAcceptAsync(Consumer<? super T> action)
Returns a new CompletionStage that, when this stage completes
normally, is executed using this stage's default asynchronous
execution facility, with this stage's result as the argument to
the supplied action.
|
CompletableFuture<Void> |
thenAcceptAsync(Consumer<? super T> action,
Executor executor)
Returns a new CompletionStage that, when this stage completes
normally, is executed using the supplied Executor, with this
stage's result as the argument to the supplied action.
|
<U> CompletableFuture<Void> |
thenAcceptBoth(CompletionStage<? extends U> other,
BiConsumer<? super T,? super U> action)
Returns a new CompletionStage that, when this and the other
given stage both complete normally, is executed with the two
results as arguments to the supplied action.
|
<U> CompletableFuture<Void> |
thenAcceptBothAsync(CompletionStage<? extends U> other,
BiConsumer<? super T,? super U> action)
Returns a new CompletionStage that, when this and the other
given stage complete normally, is executed using this stage's
default asynchronous execution facility, with the two results
as arguments to the supplied action.
|
<U> CompletableFuture<Void> |
thenAcceptBothAsync(CompletionStage<? extends U> other,
BiConsumer<? super T,? super U> action,
Executor executor)
Returns a new CompletionStage that, when this and the other
given stage complete normally, is executed using the supplied
executor, with the two results as arguments to the supplied
function.
|
<U> CompletableFuture<U> |
thenApply(Function<? super T,? extends U> fn)
Returns a new CompletionStage that, when this stage completes
normally, is executed with this stage's result as the argument
to the supplied function.
|
<U> CompletableFuture<U> |
thenApplyAsync(Function<? super T,? extends U> fn)
Returns a new CompletionStage that, when this stage completes
normally, is executed using this stage's default asynchronous
execution facility, with this stage's result as the argument to
the supplied function.
|
<U> CompletableFuture<U> |
thenApplyAsync(Function<? super T,? extends U> fn,
Executor executor)
Returns a new CompletionStage that, when this stage completes
normally, is executed using the supplied Executor, with this
stage's result as the argument to the supplied function.
|
<U,V> CompletableFuture<V> |
thenCombine(CompletionStage<? extends U> other,
BiFunction<? super T,? super U,? extends V> fn)
Returns a new CompletionStage that, when this and the other
given stage both complete normally, is executed with the two
results as arguments to the supplied function.
|
<U,V> CompletableFuture<V> |
thenCombineAsync(CompletionStage<? extends U> other,
BiFunction<? super T,? super U,? extends V> fn)
Returns a new CompletionStage that, when this and the other
given stage complete normally, is executed using this stage's
default asynchronous execution facility, with the two results
as arguments to the supplied function.
|
<U,V> CompletableFuture<V> |
thenCombineAsync(CompletionStage<? extends U> other,
BiFunction<? super T,? super U,? extends V> fn,
Executor executor)
Returns a new CompletionStage that, when this and the other
given stage complete normally, is executed using the supplied
executor, with the two results as arguments to the supplied
function.
|
<U> CompletableFuture<U> |
thenCompose(Function<? super T,? extends CompletionStage<U>> fn)
Returns a new CompletionStage that, when this stage completes
normally, is executed with this stage as the argument
to the supplied function.
|
<U> CompletableFuture<U> |
thenComposeAsync(Function<? super T,? extends CompletionStage<U>> fn)
Returns a new CompletionStage that, when this stage completes
normally, is executed using this stage's default asynchronous
execution facility, with this stage as the argument to the
supplied function.
|
<U> CompletableFuture<U> |
thenComposeAsync(Function<? super T,? extends CompletionStage<U>> fn,
Executor executor)
Returns a new CompletionStage that, when this stage completes
normally, is executed using the supplied Executor, with this
stage's result as the argument to the supplied function.
|
CompletableFuture<Void> |
thenRun(Runnable action)
Returns a new CompletionStage that, when this stage completes
normally, executes the given action.
|
CompletableFuture<Void> |
thenRunAsync(Runnable action)
Returns a new CompletionStage that, when this stage completes
normally, executes the given action using this stage's default
asynchronous execution facility.
|
CompletableFuture<Void> |
thenRunAsync(Runnable action,
Executor executor)
Returns a new CompletionStage that, when this stage completes
normally, executes the given action using the supplied Executor.
|
CompletableFuture<T> |
toCompletableFuture()
Returns this CompletableFuture.
|
String |
toString()
Returns a string identifying this CompletableFuture, as well as
its completion state.
|
CompletableFuture<T> |
whenComplete(BiConsumer<? super T,? super Throwable> action)
Returns a new CompletionStage with the same result or exception as
this stage, that executes the given action when this stage completes.
|
CompletableFuture<T> |
whenCompleteAsync(BiConsumer<? super T,? super Throwable> action)
Returns a new CompletionStage with the same result or exception as
this stage, that executes the given action using this stage's
default asynchronous execution facility when this stage completes.
|
CompletableFuture<T> |
whenCompleteAsync(BiConsumer<? super T,? super Throwable> action,
Executor executor)
Returns a new CompletionStage with the same result or exception as
this stage, that executes the given action using the supplied
Executor when this stage completes.
|
public CompletableFuture()
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier)
ForkJoinPool.commonPool()
with
the value obtained by calling the given Supplier.U
- the function's return typesupplier
- a function returning the value to be used
to complete the returned CompletableFuturepublic static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier, Executor executor)
U
- the function's return typesupplier
- a function returning the value to be used
to complete the returned CompletableFutureexecutor
- the executor to use for asynchronous executionpublic static CompletableFuture<Void> runAsync(Runnable runnable)
ForkJoinPool.commonPool()
after
it runs the given action.runnable
- the action to run before completing the
returned CompletableFuturepublic static CompletableFuture<Void> runAsync(Runnable runnable, Executor executor)
runnable
- the action to run before completing the
returned CompletableFutureexecutor
- the executor to use for asynchronous executionpublic static <U> CompletableFuture<U> completedFuture(U value)
U
- the type of the valuevalue
- the valuepublic boolean isDone()
true
if completed in any fashion: normally,
exceptionally, or via cancellation.public T get() throws InterruptedException, ExecutionException
get
in interface Future<T>
CancellationException
- if this future was cancelledExecutionException
- if this future completed exceptionallyInterruptedException
- if the current thread was interrupted
while waitingpublic T get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException
get
in interface Future<T>
timeout
- the maximum time to waitunit
- the time unit of the timeout argumentCancellationException
- if this future was cancelledExecutionException
- if this future completed exceptionallyInterruptedException
- if the current thread was interrupted
while waitingTimeoutException
- if the wait timed outpublic T join()
CompletionException
with the underlying
exception as its cause.CancellationException
- if the computation was cancelledCompletionException
- if this future completed
exceptionally or a completion computation threw an exceptionpublic T getNow(T valueIfAbsent)
valueIfAbsent
- the value to return if not completedCancellationException
- if the computation was cancelledCompletionException
- if this future completed
exceptionally or a completion computation threw an exceptionpublic boolean complete(T value)
get()
and related methods to the given value.value
- the result valuetrue
if this invocation caused this CompletableFuture
to transition to a completed state, else false
public boolean completeExceptionally(Throwable ex)
get()
and related methods to throw the given exception.ex
- the exceptiontrue
if this invocation caused this CompletableFuture
to transition to a completed state, else false
public <U> CompletableFuture<U> thenApply(Function<? super T,? extends U> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenApply
in interface CompletionStage<T>
U
- the function's return typefn
- the function to use to compute the value of
the returned CompletionStagepublic <U> CompletableFuture<U> thenApplyAsync(Function<? super T,? extends U> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenApplyAsync
in interface CompletionStage<T>
U
- the function's return typefn
- the function to use to compute the value of
the returned CompletionStagepublic <U> CompletableFuture<U> thenApplyAsync(Function<? super T,? extends U> fn, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenApplyAsync
in interface CompletionStage<T>
U
- the function's return typefn
- the function to use to compute the value of
the returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<Void> thenAccept(Consumer<? super T> action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenAccept
in interface CompletionStage<T>
action
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenAcceptAsync
in interface CompletionStage<T>
action
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> action, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenAcceptAsync
in interface CompletionStage<T>
action
- the action to perform before completing the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<Void> thenRun(Runnable action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenRun
in interface CompletionStage<T>
action
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> thenRunAsync(Runnable action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenRunAsync
in interface CompletionStage<T>
action
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> thenRunAsync(Runnable action, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenRunAsync
in interface CompletionStage<T>
action
- the action to perform before completing the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic <U,V> CompletableFuture<V> thenCombine(CompletionStage<? extends U> other, BiFunction<? super T,? super U,? extends V> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenCombine
in interface CompletionStage<T>
U
- the type of the other CompletionStage's resultV
- the function's return typeother
- the other CompletionStagefn
- the function to use to compute the value of
the returned CompletionStagepublic <U,V> CompletableFuture<V> thenCombineAsync(CompletionStage<? extends U> other, BiFunction<? super T,? super U,? extends V> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenCombineAsync
in interface CompletionStage<T>
U
- the type of the other CompletionStage's resultV
- the function's return typeother
- the other CompletionStagefn
- the function to use to compute the value of
the returned CompletionStagepublic <U,V> CompletableFuture<V> thenCombineAsync(CompletionStage<? extends U> other, BiFunction<? super T,? super U,? extends V> fn, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenCombineAsync
in interface CompletionStage<T>
U
- the type of the other CompletionStage's resultV
- the function's return typeother
- the other CompletionStagefn
- the function to use to compute the value of
the returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic <U> CompletableFuture<Void> thenAcceptBoth(CompletionStage<? extends U> other, BiConsumer<? super T,? super U> action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenAcceptBoth
in interface CompletionStage<T>
U
- the type of the other CompletionStage's resultother
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic <U> CompletableFuture<Void> thenAcceptBothAsync(CompletionStage<? extends U> other, BiConsumer<? super T,? super U> action)
CompletionStage
thenAcceptBothAsync
in interface CompletionStage<T>
U
- the type of the other CompletionStage's resultother
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic <U> CompletableFuture<Void> thenAcceptBothAsync(CompletionStage<? extends U> other, BiConsumer<? super T,? super U> action, Executor executor)
CompletionStage
thenAcceptBothAsync
in interface CompletionStage<T>
U
- the type of the other CompletionStage's resultother
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<Void> runAfterBoth(CompletionStage<?> other, Runnable action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.runAfterBoth
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> runAfterBothAsync(CompletionStage<?> other, Runnable action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.runAfterBothAsync
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> runAfterBothAsync(CompletionStage<?> other, Runnable action, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.runAfterBothAsync
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic <U> CompletableFuture<U> applyToEither(CompletionStage<? extends T> other, Function<? super T,U> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.applyToEither
in interface CompletionStage<T>
U
- the function's return typeother
- the other CompletionStagefn
- the function to use to compute the value of
the returned CompletionStagepublic <U> CompletableFuture<U> applyToEitherAsync(CompletionStage<? extends T> other, Function<? super T,U> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.applyToEitherAsync
in interface CompletionStage<T>
U
- the function's return typeother
- the other CompletionStagefn
- the function to use to compute the value of
the returned CompletionStagepublic <U> CompletableFuture<U> applyToEitherAsync(CompletionStage<? extends T> other, Function<? super T,U> fn, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.applyToEitherAsync
in interface CompletionStage<T>
U
- the function's return typeother
- the other CompletionStagefn
- the function to use to compute the value of
the returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<Void> acceptEither(CompletionStage<? extends T> other, Consumer<? super T> action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.acceptEither
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> acceptEitherAsync(CompletionStage<? extends T> other, Consumer<? super T> action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.acceptEitherAsync
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> acceptEitherAsync(CompletionStage<? extends T> other, Consumer<? super T> action, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.acceptEitherAsync
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<Void> runAfterEither(CompletionStage<?> other, Runnable action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.runAfterEither
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> runAfterEitherAsync(CompletionStage<?> other, Runnable action)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.runAfterEitherAsync
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStagepublic CompletableFuture<Void> runAfterEitherAsync(CompletionStage<?> other, Runnable action, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.runAfterEitherAsync
in interface CompletionStage<T>
other
- the other CompletionStageaction
- the action to perform before completing the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic <U> CompletableFuture<U> thenCompose(Function<? super T,? extends CompletionStage<U>> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenCompose
in interface CompletionStage<T>
U
- the type of the returned CompletionStage's resultfn
- the function returning a new CompletionStagepublic <U> CompletableFuture<U> thenComposeAsync(Function<? super T,? extends CompletionStage<U>> fn)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenComposeAsync
in interface CompletionStage<T>
U
- the type of the returned CompletionStage's resultfn
- the function returning a new CompletionStagepublic <U> CompletableFuture<U> thenComposeAsync(Function<? super T,? extends CompletionStage<U>> fn, Executor executor)
CompletionStage
CompletionStage
documentation for rules
covering exceptional completion.thenComposeAsync
in interface CompletionStage<T>
U
- the type of the returned CompletionStage's resultfn
- the function returning a new CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<T> whenComplete(BiConsumer<? super T,? super Throwable> action)
CompletionStage
When this stage is complete, the given action is invoked with the
result (or null
if none) and the exception (or null
if none) of this stage as arguments. The returned stage is completed
when the action returns. If the supplied action itself encounters an
exception, then the returned stage exceptionally completes with this
exception unless this stage also completed exceptionally.
whenComplete
in interface CompletionStage<T>
action
- the action to performpublic CompletableFuture<T> whenCompleteAsync(BiConsumer<? super T,? super Throwable> action)
CompletionStage
When this stage is complete, the given action is invoked with the
result (or null
if none) and the exception (or null
if none) of this stage as arguments. The returned stage is completed
when the action returns. If the supplied action itself encounters an
exception, then the returned stage exceptionally completes with this
exception unless this stage also completed exceptionally.
whenCompleteAsync
in interface CompletionStage<T>
action
- the action to performpublic CompletableFuture<T> whenCompleteAsync(BiConsumer<? super T,? super Throwable> action, Executor executor)
CompletionStage
When this stage is complete, the given action is invoked with the
result (or null
if none) and the exception (or null
if none) of this stage as arguments. The returned stage is completed
when the action returns. If the supplied action itself encounters an
exception, then the returned stage exceptionally completes with this
exception unless this stage also completed exceptionally.
whenCompleteAsync
in interface CompletionStage<T>
action
- the action to performexecutor
- the executor to use for asynchronous executionpublic <U> CompletableFuture<U> handle(BiFunction<? super T,Throwable,? extends U> fn)
CompletionStage
When this stage is complete, the given function is invoked
with the result (or null
if none) and the exception (or
null
if none) of this stage as arguments, and the
function's result is used to complete the returned stage.
handle
in interface CompletionStage<T>
U
- the function's return typefn
- the function to use to compute the value of the
returned CompletionStagepublic <U> CompletableFuture<U> handleAsync(BiFunction<? super T,Throwable,? extends U> fn)
CompletionStage
When this stage is complete, the given function is invoked
with the result (or null
if none) and the exception (or
null
if none) of this stage as arguments, and the
function's result is used to complete the returned stage.
handleAsync
in interface CompletionStage<T>
U
- the function's return typefn
- the function to use to compute the value of the
returned CompletionStagepublic <U> CompletableFuture<U> handleAsync(BiFunction<? super T,Throwable,? extends U> fn, Executor executor)
CompletionStage
When this stage is complete, the given function is invoked
with the result (or null
if none) and the exception (or
null
if none) of this stage as arguments, and the
function's result is used to complete the returned stage.
handleAsync
in interface CompletionStage<T>
U
- the function's return typefn
- the function to use to compute the value of the
returned CompletionStageexecutor
- the executor to use for asynchronous executionpublic CompletableFuture<T> toCompletableFuture()
toCompletableFuture
in interface CompletionStage<T>
public CompletableFuture<T> exceptionally(Function<Throwable,? extends T> fn)
whenComplete
and handle
.exceptionally
in interface CompletionStage<T>
fn
- the function to use to compute the value of the
returned CompletableFuture if this CompletableFuture completed
exceptionallypublic static CompletableFuture<Void> allOf(CompletableFuture<?>... cfs)
null
.
Among the applications of this method is to await completion
of a set of independent CompletableFutures before continuing a
program, as in: CompletableFuture.allOf(c1, c2,
c3).join();
.
cfs
- the CompletableFuturesNullPointerException
- if the array or any of its elements are
null
public static CompletableFuture<Object> anyOf(CompletableFuture<?>... cfs)
cfs
- the CompletableFuturesNullPointerException
- if the array or any of its elements are
null
public boolean cancel(boolean mayInterruptIfRunning)
CancellationException
. Dependent CompletableFutures
that have not already completed will also complete
exceptionally, with a CompletionException
caused by
this CancellationException
.public boolean isCancelled()
true
if this CompletableFuture was cancelled
before it completed normally.isCancelled
in interface Future<T>
true
if this CompletableFuture was cancelled
before it completed normallypublic boolean isCompletedExceptionally()
true
if this CompletableFuture completed
exceptionally, in any way. Possible causes include
cancellation, explicit invocation of completeExceptionally
, and abrupt termination of a
CompletionStage action.true
if this CompletableFuture completed
exceptionallypublic void obtrudeValue(T value)
get()
and related methods, whether or not
already completed. This method is designed for use only in
error recovery actions, and even in such situations may result
in ongoing dependent completions using established versus
overwritten outcomes.value
- the completion valuepublic void obtrudeException(Throwable ex)
get()
and related methods to throw the given exception, whether or
not already completed. This method is designed for use only in
error recovery actions, and even in such situations may result
in ongoing dependent completions using established versus
overwritten outcomes.ex
- the exceptionNullPointerException
- if the exception is nullpublic int getNumberOfDependents()
public String toString()
"Completed Normally"
or the String "Completed Exceptionally"
, or the String "Not
completed"
followed by the number of CompletableFutures
dependent upon its completion, if any. Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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