Module org.eclipse.jetty.util

Package org.eclipse.jetty.util

Interface Callback

All Superinterfaces:

Invocable

All Known Subinterfaces:

Blocker.Callback, Callback.Completing

All Known Implementing Classes:

Callback.Completable, Callback.Nested, CountingCallback, FutureCallback, IteratingCallback, IteratingNestedCallback, SharedBlockingCallback.Blocker

public interface Callback
extends Invocable

A callback abstraction that handles completed/failed events of asynchronous operations.

Semantically this is equivalent to an optimise Promise<Void>, but callback is a more meaningful name than EmptyPromise

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Callback.Completable	A CompletableFuture that is also a Callback.
static interface	Callback.Completing	A Callback implementation that calls the Callback.Completing.completed() method when it either succeeds or fails.
static class	Callback.Nested	Nested Completing Callback that completes after completing the nested callback

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.thread.Invocable

Invocable.Callable, Invocable.InvocationType, Invocable.ReadyTask, Invocable.Task

Field Summary

Fields

Modifier and Type	Field	Description
static final Callback	NOOP	Instance of Adapter that can be used when the callback methods need an empty implementation without incurring in the cost of allocating a new Adapter object.

Fields inherited from interface org.eclipse.jetty.util.thread.Invocable

__nonBlocking

Method Summary

Modifier and Type	Method	Description
static Callback	combine(Callback cb1, Callback cb2)
default void	completeWith(CompletableFuture<?> completable)	Completes this callback with the given CompletableFuture.
default void	failed(Throwable x)	Callback invoked when the operation fails.
static Callback	from(Runnable completed)	Creates a callback that runs completed when it succeeds or fails
static Callback	from(Runnable success, Consumer<Throwable> failure)	Creates a callback from the given success and failure lambdas.
static Callback	from(Runnable completed, Callback callback)	Creates a callback that runs the Runnable argument before completing the callback argument.
static Callback	from(CompletableFuture<?> completable)	Creates a non-blocking callback from the given incomplete CompletableFuture.
static Callback	from(CompletableFuture<?> completable, Invocable.InvocationType invocation)	Creates a callback from the given incomplete CompletableFuture, with the given blocking characteristic.
static Callback	from(Callback callback, Runnable completed)	Creates a callback that runs the Runnable argument after completing the callback argument.
static Callback	from(Callback callback, Throwable failure)	Creates a callback which always fails the callback argument on completion.
static Callback	from(Callback callback, Consumer<Throwable> completed)	Creates a callback that runs the Consumer argument after completing the callback argument.
static Callback	from(Callback callback1, Callback callback2)	Creates a callback which combines two other callbacks and will succeed or fail them both.
static Callback	from(Invocable.InvocationType invocationType, Runnable completed)	Creates a Callback with the given invocationType, that runs the given Runnable when it succeeds or fails.
static Callback	from(Invocable.InvocationType invocationType, Runnable success, Consumer<Throwable> failure)	Creates a callback with the given InvocationType from the given success and failure lambdas.
default void	succeeded()	Callback invoked when the operation completes.

Methods inherited from interface org.eclipse.jetty.util.thread.Invocable

getInvocationType

Field Details

NOOP

static final Callback NOOP

Instance of Adapter that can be used when the callback methods need an empty implementation without incurring in the cost of allocating a new Adapter object.

Method Details

completeWith

default void completeWith(CompletableFuture<?> completable)

Completes this callback with the given CompletableFuture.

When the CompletableFuture completes normally, this callback is succeeded; when the CompletableFuture completes exceptionally, this callback is failed.

Parameters:

completable - the CompletableFuture that completes this callback

succeeded

default void succeeded()

Callback invoked when the operation completes.

See Also:

• failed(Throwable)

failed

default void failed(Throwable x)

Callback invoked when the operation fails.

Parameters:

x - the reason for the operation failure

from

static Callback from(CompletableFuture<?> completable)

Creates a non-blocking callback from the given incomplete CompletableFuture.

When the callback completes, either succeeding or failing, the CompletableFuture is also completed, respectively via CompletableFuture.complete(Object) or CompletableFuture.completeExceptionally(Throwable).

Parameters:

completable - the CompletableFuture to convert into a callback

Returns:

a callback that when completed, completes the given CompletableFuture

from

static Callback from(CompletableFuture<?> completable,
 Invocable.InvocationType invocation)

Creates a callback from the given incomplete CompletableFuture, with the given blocking characteristic.

Parameters:

completable - the CompletableFuture to convert into a callback

invocation - whether the callback is blocking

Returns:

a callback that when completed, completes the given CompletableFuture

from

static Callback from(Runnable success,
 Consumer<Throwable> failure)

Creates a callback from the given success and failure lambdas.

Parameters:

success - Called when the callback succeeds

failure - Called when the callback fails

Returns:

a new Callback

from

static Callback from(Invocable.InvocationType invocationType,
 Runnable success,
 Consumer<Throwable> failure)

Creates a callback with the given InvocationType from the given success and failure lambdas.

Parameters:

invocationType - the Callback invocation type

success - Called when the callback succeeds

failure - Called when the callback fails

Returns:

a new Callback

from

static Callback from(Runnable completed)

Creates a callback that runs completed when it succeeds or fails

Parameters:

completed - The completion to run on success or failure

Returns:

a new callback

from

static Callback from(Invocable.InvocationType invocationType,
 Runnable completed)

Creates a Callback with the given invocationType, that runs the given Runnable when it succeeds or fails.

Parameters:

invocationType - the invocation type of the returned Callback

completed - the Runnable to run when the callback either succeeds or fails

Returns:

a new Callback with the given invocation type

from

static Callback from(Callback callback,
 Runnable completed)

Creates a callback that runs the Runnable argument after completing the callback argument.

The Runnable is assumed to be NON_BLOCKING, so the Invocable.InvocationType of the returned callback is the same as the callback argument.

Parameters:

callback - The nested callback

completed - The Runnable to run after the nested callback is completed

Returns:

a new callback

from

static Callback from(Callback callback,
 Consumer<Throwable> completed)

Creates a callback that runs the Consumer argument after completing the callback argument.

The Consumer receives null if the callback succeeded, or the Throwable failure if the callback failed.

The Consumer is assumed to be NON_BLOCKING, so the Invocable.InvocationType of the returned callback is the same as the callback parameter.

Parameters:

callback - The nested callback

completed - The Consumer to run after the nested callback is completed

Returns:

a new callback

from

static Callback from(Runnable completed,
 Callback callback)

Creates a callback that runs the Runnable argument before completing the callback argument.

The Runnable is assumed to be NON_BLOCKING, so the Invocable.InvocationType of the returned callback is the same as the callback argument.

Parameters:

completed - The Runnable to run before the nested callback is completed. Any exceptions thrown from the Runnable will result in the callback failure.

callback - The nested callback

Returns:

a new callback

from

static Callback from(Callback callback,
 Throwable failure)

Creates a callback which always fails the callback argument on completion.

Parameters:

callback - The nested callback

failure - The cause to fail the nested callback; if the new callback is failed, the cause will be added to the failure argument as a suppressed exception.

Returns:

a new callback.

from

static Callback from(Callback callback1,
 Callback callback2)

Creates a callback which combines two other callbacks and will succeed or fail them both.

Parameters:

callback1 - The first callback

callback2 - The second callback

Returns:

a new callback.

combine

static Callback combine(Callback cb1,
 Callback cb2)