org.apache.kafka.common

Class KafkaFuture<T>

java.lang.Object

org.apache.kafka.common.KafkaFuture<T>

All Implemented Interfaces:

java.util.concurrent.Future<T>

@InterfaceStability.Evolving
public abstract class KafkaFuture<T>
extends java.lang.Object
implements java.util.concurrent.Future<T>

A flexible future which supports call chaining and other asynchronous programming patterns. This will eventually become a thin shim on top of Java 8's CompletableFuture. The API for this class is still evolving and we may break compatibility in minor releases, if necessary.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	KafkaFuture.BiConsumer<A,B> A consumer of two different types of object.
static class	KafkaFuture.Function<A,B> A function which takes objects of type A and returns objects of type B.

Constructor Summary

Constructors

Constructor and Description
KafkaFuture()

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract void	addWaiter(KafkaFuture.BiConsumer<? super T,? super java.lang.Throwable> action)
static KafkaFuture<java.lang.Void>	allOf(KafkaFuture<?>... futures) Returns a new KafkaFuture that is completed when all the given futures have completed.
abstract boolean	cancel(boolean mayInterruptIfRunning) If not already completed, completes this future with a CancellationException.
protected abstract boolean	complete(T newValue) If not already completed, sets the value returned by get() and related methods to the given value.
static <U> KafkaFuture<U>	completedFuture(U value) Returns a new KafkaFuture that is already completed with the given value.
protected abstract boolean	completeExceptionally(java.lang.Throwable newException) If not already completed, causes invocations of get() and related methods to throw the given exception.
abstract T	get() Waits if necessary for this future to complete, and then returns its result.
abstract T	get(long timeout, java.util.concurrent.TimeUnit unit) Waits if necessary for at most the given time for this future to complete, and then returns its result, if available.
abstract T	getNow(T valueIfAbsent) Returns the result value (or throws any encountered exception) if completed, else returns the given valueIfAbsent.
abstract boolean	isCancelled() Returns true if this CompletableFuture was cancelled before it completed normally.
abstract boolean	isCompletedExceptionally() Returns true if this CompletableFuture completed exceptionally, in any way.
abstract boolean	isDone() Returns true if completed in any fashion: normally, exceptionally, or via cancellation.
abstract <R> KafkaFuture<R>	thenApply(KafkaFuture.Function<T,R> function) Returns a new KafkaFuture that, when this future completes normally, is executed with this futures's result as the argument to the supplied function.

Methods inherited from class java.lang.Object

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

Constructor Detail

KafkaFuture

public KafkaFuture()

Method Detail

completedFuture

public static <U> KafkaFuture<U> completedFuture(U value)

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

allOf

public static KafkaFuture<java.lang.Void> allOf(KafkaFuture<?>... futures)

Returns a new KafkaFuture that is completed when all the given futures have completed. If any future throws an exception, the returned future returns it. If multiple futures throw an exception, which one gets returned is arbitrarily chosen.

thenApply

public abstract <R> KafkaFuture<R> thenApply(KafkaFuture.Function<T,R> function)

Returns a new KafkaFuture that, when this future completes normally, is executed with this futures's result as the argument to the supplied function.

addWaiter

protected abstract void addWaiter(KafkaFuture.BiConsumer<? super T,? super java.lang.Throwable> action)

complete

protected abstract boolean complete(T newValue)

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

completeExceptionally

protected abstract boolean completeExceptionally(java.lang.Throwable newException)

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

cancel

public abstract boolean cancel(boolean mayInterruptIfRunning)

If not already completed, completes this future with a CancellationException. Dependent futures that have not already completed will also complete exceptionally, with a CompletionException caused by this CancellationException.

Specified by:

cancel in interface java.util.concurrent.Future<T>

get

public abstract T get()
               throws java.lang.InterruptedException,
                      java.util.concurrent.ExecutionException

Waits if necessary for this future to complete, and then returns its result.

Specified by:

get in interface java.util.concurrent.Future<T>

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

get

public abstract T get(long timeout,
    java.util.concurrent.TimeUnit unit)
               throws java.lang.InterruptedException,
                      java.util.concurrent.ExecutionException,
                      java.util.concurrent.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 java.util.concurrent.Future<T>

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

java.util.concurrent.TimeoutException

getNow

public abstract T getNow(T valueIfAbsent)
                  throws java.lang.InterruptedException,
                         java.util.concurrent.ExecutionException

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

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

isCancelled

public abstract boolean isCancelled()

Returns true if this CompletableFuture was cancelled before it completed normally.

Specified by:

isCancelled in interface java.util.concurrent.Future<T>

isCompletedExceptionally

public abstract boolean isCompletedExceptionally()

Returns true if this CompletableFuture completed exceptionally, in any way.

isDone

public abstract boolean isDone()

Returns true if completed in any fashion: normally, exceptionally, or via cancellation.

Specified by:

isDone in interface java.util.concurrent.Future<T>