org.apache.pulsar.common.util

Class FutureUtil

java.lang.Object

org.apache.pulsar.common.util.FutureUtil

public class FutureUtil
extends Object

This class is aimed at simplifying work with CompletableFuture.

Constructor Summary

Constructors

Constructor and Description
FutureUtil()

Method Summary

Modifier and Type	Method and Description
static <T> CompletableFuture<T>	addTimeoutHandling(CompletableFuture<T> future, Duration timeout, ScheduledExecutorService executor, Supplier<Throwable> exceptionSupplier) Adds timeout handling to an existing CompletableFuture.
static <T> CompletableFuture<T>	createFutureWithTimeout(Duration timeout, ScheduledExecutorService executor, Supplier<Throwable> exceptionSupplier) Creates a new CompletableFuture instance with timeout handling.
static TimeoutException	createTimeoutException(String message, Class<?> sourceClass, String sourceMethod) Creates a low-overhead timeout exception which is performance optimized to minimize allocations and cpu consumption.
static <T> CompletableFuture<T>	failedFuture(Throwable t)
static Throwable	unwrapCompletionException(Throwable t)
static CompletableFuture<Void>	waitForAll(List<? extends CompletableFuture<?>> futures) Return a future that represents the completion of the futures in the provided list.
static CompletableFuture<Void>	waitForAllAndSupportCancel(List<? extends CompletableFuture<?>> futures) Return a future that represents the completion of the futures in the provided list.
static void	whenCancelledOrTimedOut(CompletableFuture<?> future, Runnable cancelAction) If the future is cancelled or times out, the cancel action will be invoked The action is executed once if the future completes with CancellationException or TimeoutException

Methods inherited from class java.lang.Object

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

Constructor Detail

FutureUtil

public FutureUtil()

Method Detail

waitForAll

public static CompletableFuture<Void> waitForAll(List<? extends CompletableFuture<?>> futures)

Return a future that represents the completion of the futures in the provided list.

Parameters:

futures - futures to wait for

Returns:

a new CompletableFuture that is completed when all of the given CompletableFutures complete

waitForAllAndSupportCancel

public static CompletableFuture<Void> waitForAllAndSupportCancel(List<? extends CompletableFuture<?>> futures)

Return a future that represents the completion of the futures in the provided list. The future will support CompletableFuture.cancel(boolean). It will cancel all unfinished futures when the future gets cancelled.

Parameters:

futures - futures to wait for

Returns:

a new CompletableFuture that is completed when all of the given CompletableFutures complete

whenCancelledOrTimedOut

public static void whenCancelledOrTimedOut(CompletableFuture<?> future,
                                           Runnable cancelAction)

If the future is cancelled or times out, the cancel action will be invoked The action is executed once if the future completes with CancellationException or TimeoutException

Parameters:

future - future to attach the action to

cancelAction - action to invoke if the future is cancelled or times out

failedFuture

public static <T> CompletableFuture<T> failedFuture(Throwable t)

unwrapCompletionException

public static Throwable unwrapCompletionException(Throwable t)

createFutureWithTimeout

public static <T> CompletableFuture<T> createFutureWithTimeout(Duration timeout,
                                                               ScheduledExecutorService executor,
                                                               Supplier<Throwable> exceptionSupplier)

Creates a new CompletableFuture instance with timeout handling.

Type Parameters:

T - type parameter for the future

Parameters:

timeout - the duration of the timeout

executor - the executor to use for scheduling the timeout

exceptionSupplier - the supplier for creating the exception

Returns:

the new CompletableFuture instance

addTimeoutHandling

public static <T> CompletableFuture<T> addTimeoutHandling(CompletableFuture<T> future,
                                                          Duration timeout,
                                                          ScheduledExecutorService executor,
                                                          Supplier<Throwable> exceptionSupplier)

Adds timeout handling to an existing CompletableFuture.

Type Parameters:

T - type parameter for the future

Parameters:

future - the target future

timeout - the duration of the timeout

executor - the executor to use for scheduling the timeout

exceptionSupplier - the supplier for creating the exception

Returns:

returns the original target future

createTimeoutException

public static TimeoutException createTimeoutException(String message,
                                                      Class<?> sourceClass,
                                                      String sourceMethod)

Creates a low-overhead timeout exception which is performance optimized to minimize allocations and cpu consumption. It sets the stacktrace of the exception to the given source class and source method name. The instances of this class can be cached or stored as constants and reused multiple times.

Parameters:

message - exception message

sourceClass - source class for manually filled in stacktrace

sourceMethod - source method name for manually filled in stacktrace

Returns:

new TimeoutException instance