esfand/completablefuture.md

## completablefuture.md

      
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              completablefuture.md
            
          
    Class CompletableFuture Class

public class CompletableFuture<> extends `Object`
implements interface in Future, CompletionStage<>
A 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: 

 
Actions supplied for dependent completions of
 non-async methods may be performed by the thread that
 completes the current CompletableFuture, or by any other caller of
 a completion method.

 
All async methods without an explicit Executor
 argument are performed using the `ForkJoinPool.commonPool()`
 (unless it does not support a parallelism level of at least two, in
 which case, a new Thread is used). To simplify monitoring,
 debugging, and tracking, all generated asynchronous tasks are
 instances of the marker interface 
`CompletableFuture.AsynchronousCompletionTask`. 

 All CompletionStage methods are implemented independently of
 other public methods, so the behavior of one method is not impacted
 by overrides of others in subclasses.  
 
 CompletableFuture also implements Future with the following
 policies: 


Since (unlike `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.


In case of exceptional completion with a CompletionException, methods `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.
 

Nested Class Summary

static interface  CompletableFuture.AsynchronousCompletionTask

A marker interface identifying asynchronous tasks produced by async methods.

Constructor Summary

CompletableFuture()

Creates a new incomplete CompletableFuture.

Method Summary

Static Methods


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.
static <U> CompletableFuture<U>  completedFuture(U value)

Returns a new CompletableFuture that is already completed with the given value.

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.

Instance Methods


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.

All Methods
 

Static Methods Instance Methods Concrete Methods 


Modifier and Type
Method and Description


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
See the CompletionStage documentation for rules
covering exceptional completion.


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 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, and when this stage completes, executes the
 given action with the result (or null if none) and the
 exception (or null if none) of this stage.


CompletableFuture<T>
whenCompleteAsync(BiConsumer<? super T,? super Throwable> action)
Returns a new CompletionStage with the same result or exception
 as this stage, and when this stage completes, executes the
 given action executes the given action using this stage's
 default asynchronous execution facility, with the result (or
 null if none) and the exception (or null if
 none) of this stage as arguments.


CompletableFuture<T>
whenCompleteAsync(BiConsumer<? super T,? super Throwable> action,
                 Executor executor)
Returns a new CompletionStage with the same result or exception
 as this stage, and when this stage completes, executes using
 the supplied Executor, the given action with the result (or
 null if none) and the exception (or null if
 none) of this stage as arguments.


Methods inherited from class java.lang.Object


clone, 
equals, 
finalize,
getClass, 
hashCode, 
notify, 
notifyAll, 
wait, 
wait, 
wait


Constructor Detail

CompletableFuture

public CompletableFuture()

Method Detail


supplyAsync

public 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.

Type Parameters:
U - the function's return type
Parameters:
supplier - a function returning the value to be used
 to complete the returned CompletableFuture
Returns:
the new CompletableFuture


supplyAsync

public 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.

Type Parameters:
U - the function's return type
Parameters:
supplier - a function returning the value to be used
 to complete the returned CompletableFuture
executor - the executor to use for asynchronous execution
Returns:
the new CompletableFuture


runAsync

public 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.

Parameters:
runnable - the action to run before completing the
 returned CompletableFuture
Returns:
the new CompletableFuture


runAsync

public 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.

Parameters:
runnable - the action to run before completing the
 returned CompletableFuture
executor - the executor to use for asynchronous execution
Returns:
the new CompletableFuture


completedFuture

public static <U> CompletableFuture<U> completedFuture(U value)
Returns a new CompletableFuture that is already completed with
 the given value.

Type Parameters:
U - the type of the value
Parameters:
value - the value
Returns:
the completed CompletableFuture


isDone

public boolean isDone()
Returns true if completed in any fashion: normally,
 exceptionally, or via cancellation.

Specified by:
isDone in interface Future<T>
Returns:
true if completed


get

public T get()
      throws InterruptedException,
             ExecutionException
Waits if necessary for this future to complete, and then
 returns its result.

Specified by:
get in interface Future<T>
Returns:
the result value
Throws:
CancellationException - if this future was cancelled
ExecutionException - if this future completed exceptionally
InterruptedException - if the current thread was interrupted
 while waiting


get

public T get(long timeout,
             TimeUnit unit)
      throws InterruptedException,
             ExecutionException,
             TimeoutException
Waits if necessary for at most the given time for this future
 to complete, and then returns its result, if available.

Specified by:
get in interface Future<T>
Parameters:
timeout - the maximum time to wait
unit - the time unit of the timeout argument
Returns:
the result value
Throws:
CancellationException - if this future was cancelled
ExecutionException - if this future completed exceptionally
InterruptedException - if the current thread was interrupted
 while waiting
TimeoutException - if the wait timed out


join

public T join()
Returns the result value when complete, or throws an
 (unchecked) exception if completed exceptionally. To better
 conform with the use of common functional forms, if a
 computation involved in the completion of this
 CompletableFuture threw an exception, this method throws an
 (unchecked) CompletionException with the underlying
 exception as its cause.

Returns:
the result value
Throws:
CancellationException - if the computation was cancelled
CompletionException - if this future completed
 exceptionally or a completion computation threw an exception


getNow

public T getNow(T valueIfAbsent)
Returns the result value (or throws any encountered exception)
 if completed, else returns the given valueIfAbsent.

Parameters:
valueIfAbsent - the value to return if not completed
Returns:
the result value, if completed, else the given valueIfAbsent
Throws:
CancellationException - if the computation was cancelled
CompletionException - if this future completed
 exceptionally or a completion computation threw an exception


complete

public boolean complete(T value)
If not already completed, sets the value returned by get() and related methods to the given value.

Parameters:
value - the result value
Returns:
true if this invocation caused this CompletableFuture
 to transition to a completed state, else false


completeExceptionally

public boolean completeExceptionally(Throwable ex)
If not already completed, causes invocations of get()
 and related methods to throw the given exception.

Parameters:
ex - the exception
Returns:
true if this invocation caused this CompletableFuture
 to transition to a completed state, else false


thenApply

public <U> CompletableFuture<U> thenApply(Function<? super T,? extends U> fn)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this stage completes
 normally, is executed with this stage's result as the argument
 to the supplied function.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenApply in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
fn - the function to use to compute the value of
 the returned CompletionStage
Returns:
the new CompletionStage


thenApplyAsync

public <U> CompletableFuture<U> thenApplyAsync(Function<? super T,? extends U> fn)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenApplyAsync in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
fn - the function to use to compute the value of
 the returned CompletionStage
Returns:
the new CompletionStage


thenApplyAsync

public <U> CompletableFuture<U> thenApplyAsync(Function<? super T,? extends U> fn,
                                               Executor executor)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenApplyAsync in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
fn - the function to use to compute the value of
 the returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


thenAccept

public CompletableFuture<Void> thenAccept(Consumer<? super T> action)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this stage completes
 normally, is executed with this stage's result as the argument
 to the supplied action.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenAccept in interface CompletionStage<T>
Parameters:
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


thenAcceptAsync

public CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> action)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenAcceptAsync in interface CompletionStage<T>
Parameters:
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


thenAcceptAsync

public CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> action,
                                               Executor executor)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenAcceptAsync in interface CompletionStage<T>
Parameters:
action - the action to perform before completing the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


thenRun

public CompletableFuture<Void> thenRun(Runnable action)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this stage completes
 normally, executes the given action.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenRun in interface CompletionStage<T>
Parameters:
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


thenRunAsync

public CompletableFuture<Void> thenRunAsync(Runnable action)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this stage completes
 normally, executes the given action using this stage's default
 asynchronous execution facility.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenRunAsync in interface CompletionStage<T>
Parameters:
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


thenRunAsync

public CompletableFuture<Void> thenRunAsync(Runnable action,
                                            Executor executor)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this stage completes
 normally, executes the given action using the supplied Executor.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenRunAsync in interface CompletionStage<T>
Parameters:
action - the action to perform before completing the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


thenCombine

public <U,V> CompletableFuture<V> thenCombine(CompletionStage<? extends U> other,
                                              BiFunction<? super T,? super U,? extends V> fn)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenCombine in interface CompletionStage<T>
Type Parameters:
U - the type of the other CompletionStage's result
V - the function's return type
Parameters:
other - the other CompletionStage
fn - the function to use to compute the value of
 the returned CompletionStage
Returns:
the new CompletionStage


thenCombineAsync

public <U,V> CompletableFuture<V> thenCombineAsync(CompletionStage<? extends U> other,
                                                   BiFunction<? super T,? super U,? extends V> fn)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenCombineAsync in interface CompletionStage<T>
Type Parameters:
U - the type of the other CompletionStage's result
V - the function's return type
Parameters:
other - the other CompletionStage
fn - the function to use to compute the value of
 the returned CompletionStage
Returns:
the new CompletionStage


thenCombineAsync

public <U,V> CompletableFuture<V> thenCombineAsync(CompletionStage<? extends U> other,
                                                   BiFunction<? super T,? super U,? extends V> fn,
                                                   Executor executor)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenCombineAsync in interface CompletionStage<T>
Type Parameters:
U - the type of the other CompletionStage's result
V - the function's return type
Parameters:
other - the other CompletionStage
fn - the function to use to compute the value of
 the returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


thenAcceptBoth

public <U> CompletableFuture<Void> thenAcceptBoth(CompletionStage<? extends U> other,
                                                  BiConsumer<? super T,? super U> action)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenAcceptBoth in interface CompletionStage<T>
Type Parameters:
U - the type of the other CompletionStage's result
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


thenAcceptBothAsync

public <U> CompletableFuture<Void> thenAcceptBothAsync(CompletionStage<? extends U> other,
                                                       BiConsumer<? super T,? super U> action)
Description copied from interface: CompletionStage
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.

Specified by:
thenAcceptBothAsync in interface CompletionStage<T>
Type Parameters:
U - the type of the other CompletionStage's result
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


thenAcceptBothAsync

public <U> CompletableFuture<Void> thenAcceptBothAsync(CompletionStage<? extends U> other,
                                                       BiConsumer<? super T,? super U> action,
                                                       Executor executor)
Description copied from interface: CompletionStage
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.

Specified by:
thenAcceptBothAsync in interface CompletionStage<T>
Type Parameters:
U - the type of the other CompletionStage's result
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


runAfterBoth

public CompletableFuture<Void> runAfterBoth(CompletionStage<?> other,
                                            Runnable action)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this and the other
 given stage both complete normally, executes the given action.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
runAfterBoth in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


runAfterBothAsync

public CompletableFuture<Void> runAfterBothAsync(CompletionStage<?> other,
                                                 Runnable action)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
runAfterBothAsync in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


runAfterBothAsync

public CompletableFuture<Void> runAfterBothAsync(CompletionStage<?> other,
                                                 Runnable action,
                                                 Executor executor)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this and the other
 given stage complete normally, executes the given action using
 the supplied executor
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
runAfterBothAsync in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


applyToEither

public <U> CompletableFuture<U> applyToEither(CompletionStage<? extends T> other,
                                              Function<? super T,U> fn)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
applyToEither in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
other - the other CompletionStage
fn - the function to use to compute the value of
 the returned CompletionStage
Returns:
the new CompletionStage


applyToEitherAsync

public <U> CompletableFuture<U> applyToEitherAsync(CompletionStage<? extends T> other,
                                                   Function<? super T,U> fn)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
applyToEitherAsync in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
other - the other CompletionStage
fn - the function to use to compute the value of
 the returned CompletionStage
Returns:
the new CompletionStage


applyToEitherAsync

public <U> CompletableFuture<U> applyToEitherAsync(CompletionStage<? extends T> other,
                                                   Function<? super T,U> fn,
                                                   Executor executor)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
applyToEitherAsync in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
other - the other CompletionStage
fn - the function to use to compute the value of
 the returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


acceptEither

public CompletableFuture<Void> acceptEither(CompletionStage<? extends T> other,
                                            Consumer<? super T> action)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
acceptEither in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


acceptEitherAsync

public CompletableFuture<Void> acceptEitherAsync(CompletionStage<? extends T> other,
                                                 Consumer<? super T> action)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
acceptEitherAsync in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


acceptEitherAsync

public CompletableFuture<Void> acceptEitherAsync(CompletionStage<? extends T> other,
                                                 Consumer<? super T> action,
                                                 Executor executor)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
acceptEitherAsync in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


runAfterEither

public CompletableFuture<Void> runAfterEither(CompletionStage<?> other,
                                              Runnable action)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when either this or the
 other given stage complete normally, executes the given action.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
runAfterEither in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


runAfterEitherAsync

public CompletableFuture<Void> runAfterEitherAsync(CompletionStage<?> other,
                                                   Runnable action)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
runAfterEitherAsync in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
Returns:
the new CompletionStage


runAfterEitherAsync

public CompletableFuture<Void> runAfterEitherAsync(CompletionStage<?> other,
                                                   Runnable action,
                                                   Executor executor)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when either this or the
 other given stage complete normally, executes the given action
 using supplied executor.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
runAfterEitherAsync in interface CompletionStage<T>
Parameters:
other - the other CompletionStage
action - the action to perform before completing the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


thenCompose

public <U> CompletableFuture<U> thenCompose(Function<? super T,? extends CompletionStage<U>> fn)
Description copied from interface: CompletionStage
Returns a new CompletionStage that, when this stage completes
 normally, is executed with this stage as the argument
 to the supplied function.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenCompose in interface CompletionStage<T>
Type Parameters:
U - the type of the returned CompletionStage's result
Parameters:
fn - the function returning a new CompletionStage
Returns:
the CompletionStage


thenComposeAsync

public <U> CompletableFuture<U> thenComposeAsync(Function<? super T,? extends CompletionStage<U>> fn)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenComposeAsync in interface CompletionStage<T>
Type Parameters:
U - the type of the returned CompletionStage's result
Parameters:
fn - the function returning a new CompletionStage
Returns:
the CompletionStage


thenComposeAsync

public <U> CompletableFuture<U> thenComposeAsync(Function<? super T,? extends CompletionStage<U>> fn,
                                                 Executor executor)
Description copied from interface: CompletionStage
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.
See the CompletionStage documentation for rules
covering exceptional completion.


Specified by:
thenComposeAsync in interface CompletionStage<T>
Type Parameters:
U - the type of the returned CompletionStage's result
Parameters:
fn - the function returning a new CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the CompletionStage


whenComplete

public CompletableFuture<T> whenComplete(BiConsumer<? super T,? super Throwable> action)
Description copied from interface: CompletionStage
Returns a new CompletionStage with the same result or exception
 as this stage, and when this stage completes, executes the
 given action with the result (or null if none) and the
 exception (or null if none) of this stage.

Specified by:
whenComplete in interface CompletionStage<T>
Parameters:
action - the action to perform
Returns:
the new CompletionStage


whenCompleteAsync

public CompletableFuture<T> whenCompleteAsync(BiConsumer<? super T,? super Throwable> action)
Description copied from interface: CompletionStage
Returns a new CompletionStage with the same result or exception
 as this stage, and when this stage completes, executes the
 given action executes the given action using this stage's
 default asynchronous execution facility, with the result (or
 null if none) and the exception (or null if
 none) of this stage as arguments.

Specified by:
whenCompleteAsync in interface CompletionStage<T>
Parameters:
action - the action to perform
Returns:
the new CompletionStage


whenCompleteAsync

public CompletableFuture<T> whenCompleteAsync(BiConsumer<? super T,? super Throwable> action,
                                              Executor executor)
Description copied from interface: CompletionStage
Returns a new CompletionStage with the same result or exception
 as this stage, and when this stage completes, executes using
 the supplied Executor, the given action with the result (or
 null if none) and the exception (or null if
 none) of this stage as arguments.

Specified by:
whenCompleteAsync in interface CompletionStage<T>
Parameters:
action - the action to perform
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


handle

public <U> CompletableFuture<U> handle(BiFunction<? super T,Throwable,? extends U> fn)
Description copied from interface: CompletionStage
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.
 The given function is invoked with the result (or null
 if none) and the exception (or null if none) of this
 stage when complete as arguments.

Specified by:
handle in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
fn - the function to use to compute the value of the
 returned CompletionStage
Returns:
the new CompletionStage


handleAsync

public <U> CompletableFuture<U> handleAsync(BiFunction<? super T,Throwable,? extends U> fn)
Description copied from interface: CompletionStage
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.
 The given function is invoked with the result (or null
 if none) and the exception (or null if none) of this
 stage when complete as arguments.

Specified by:
handleAsync in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
fn - the function to use to compute the value of the
 returned CompletionStage
Returns:
the new CompletionStage


handleAsync

public <U> CompletableFuture<U> handleAsync(BiFunction<? super T,Throwable,? extends U> fn,
                                            Executor executor)
Description copied from interface: CompletionStage
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.  The given function is
 invoked with the result (or null if none) and the
 exception (or null if none) of this stage when complete
 as arguments.

Specified by:
handleAsync in interface CompletionStage<T>
Type Parameters:
U - the function's return type
Parameters:
fn - the function to use to compute the value of the
 returned CompletionStage
executor - the executor to use for asynchronous execution
Returns:
the new CompletionStage


toCompletableFuture

public CompletableFuture<T> toCompletableFuture()
Returns this CompletableFuture

Specified by:
toCompletableFuture in interface CompletionStage<T>
Returns:
this CompletableFuture


exceptionally

public 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.
 Note: More flexible versions of this functionality are
 available using methods whenComplete and handle.

Specified by:
exceptionally in interface CompletionStage<T>
Parameters:
fn - the function to use to compute the value of the
 returned CompletableFuture if this CompletableFuture completed
 exceptionally
Returns:
the new CompletableFuture


allOf

public static CompletableFuture<Void> allOf(CompletableFuture<?>... cfs)
Returns a new CompletableFuture that is completed when all of
 the given CompletableFutures complete.  If any of the given
 CompletableFutures complete exceptionally, then the returned
 CompletableFuture also does so, with a CompletionException
 holding this exception as its cause.  Otherwise, the results,
 if any, of the given CompletableFutures are not reflected in
 the returned CompletableFuture, but may be obtained by
 inspecting them individually. If no CompletableFutures are
 provided, returns a CompletableFuture completed with the value
 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();.

Parameters:
cfs - the CompletableFutures
Returns:
a new CompletableFuture that is completed when all of the
 given CompletableFutures complete
Throws:
NullPointerException - if the array or any of its elements are
 null


anyOf

public static CompletableFuture<Object> anyOf(CompletableFuture<?>... cfs)
Returns a new CompletableFuture that is completed when any of
 the given CompletableFutures complete, with the same result.
 Otherwise, if it completed exceptionally, the returned
 CompletableFuture also does so, with a CompletionException
 holding this exception as its cause.  If no CompletableFutures
 are provided, returns an incomplete CompletableFuture.

Parameters:
cfs - the CompletableFutures
Returns:
a new CompletableFuture that is completed with the
 result or exception of any of the given CompletableFutures when
 one completes
Throws:
NullPointerException - if the array or any of its elements are
 null


cancel

public boolean cancel(boolean mayInterruptIfRunning)
If not already completed, completes this CompletableFuture with
 a CancellationException. Dependent CompletableFutures
 that have not already completed will also complete
 exceptionally, with a CompletionException caused by
 this CancellationException.

Specified by:
cancel in interface Future<T>
Parameters:
mayInterruptIfRunning - this value has no effect in this
 implementation because interrupts are not used to control
 processing.
Returns:
true if this task is now cancelled


isCancelled

public boolean isCancelled()
Returns true if this CompletableFuture was cancelled
 before it completed normally.

Specified by:
isCancelled in interface Future<T>
Returns:
true if this CompletableFuture was cancelled
 before it completed normally


isCompletedExceptionally

public boolean isCompletedExceptionally()
Returns true if this CompletableFuture completed
 exceptionally, in any way. Possible causes include
 cancellation, explicit invocation of completeExceptionally, and abrupt termination of a
 CompletionStage action.

Returns:
true if this CompletableFuture completed
 exceptionally


obtrudeValue

public void obtrudeValue(T value)
Forcibly sets or resets the value subsequently returned by
 method 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.

Parameters:
value - the completion value


obtrudeException

public void obtrudeException(Throwable ex)
Forcibly causes subsequent invocations of method get()
 and related methods to throw the given exception, whether or
 not already completed. This method is designed for use only in
 recovery actions, and even in such situations may result in
 ongoing dependent completions using established versus
 overwritten outcomes.

Parameters:
ex - the exception


getNumberOfDependents

public int getNumberOfDependents()
Returns the estimated number of CompletableFutures whose
 completions are awaiting completion of this CompletableFuture.
 This method is designed for use in monitoring system state, not
 for synchronization control.

Returns:
the number of dependent CompletableFutures


toString

public String toString()
Returns a string identifying this CompletableFuture, as well as
 its completion state.  The state, in brackets, contains the
 String "Completed Normally" or the String "Completed Exceptionally", or the String "Not
 completed" followed by the number of CompletableFutures
 dependent upon its completion, if any.

Overrides:
toString in class Object
Returns:
a string identifying this CompletableFuture, as well as its state
Modifier and Type	Method and Description
`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 See the `CompletionStage` documentation for rules covering exceptional completion.
`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 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, and when this stage completes, executes the given action with the result (or `null` if none) and the exception (or `null` if none) of this stage.
`CompletableFuture<T>`	`whenCompleteAsync(BiConsumer<? super T,? super Throwable> action)` Returns a new CompletionStage with the same result or exception as this stage, and when this stage completes, executes the given action executes the given action using this stage's default asynchronous execution facility, with the result (or `null` if none) and the exception (or `null` if none) of this stage as arguments.
`CompletableFuture<T>`	`whenCompleteAsync(BiConsumer<? super T,? super Throwable> action, Executor executor)` Returns a new CompletionStage with the same result or exception as this stage, and when this stage completes, executes using the supplied Executor, the given action with the result (or `null` if none) and the exception (or `null` if none) of this stage as arguments.