de.skuzzle.inject.async.util

Class Futures

java.lang.Object

de.skuzzle.inject.async.util.Futures

public final class Futures
extends Object

Utility to create dummy Future objects to use in methods annotated with Async.

Author:

Simon Taddiken

Method Summary

Modifier and Type	Method and Description
static <T> Future<T>	delegate(T obj) Returns a dummy Future object to be used to return a value in methods that are annotated with Async.
static <T> CompletableFuture<T>	delegateCompletable(T obj) Returns a dummy CompletableFuture object to be used to return a value in methods that are annotated with Async.

Methods inherited from class java.lang.Object

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

Method Detail

delegateCompletable

public static <T> CompletableFuture<T> delegateCompletable(T obj)

Returns a dummy CompletableFuture object to be used to return a value in methods that are annotated with Async. Sample usage:

 @Async
 public CompletableFuture<Integer> calculateAsync() {
     final Integer result = doHeavyCalculation();
     return Futures.delegateCompletable(result);
 }
 

You should not use the returned dummy object for any other purpose than returning it from a method which is annotated with Async.

API Note
The MethodInterceptor which handles the asynchronous invocations will extract the wrapped Object from this dummy CompletableFuture and create an actual CompletableFuture which is backed by the ExecutorService in place. Thus, the dummy Object created here will never leave the context of the method it is created in (if you do not manually leak it to the outside).

Type Parameters:

T - Type of the Object to return.

Parameters:

obj - The Object to return.

Returns:

The dummy object.

Since:

1.1.0

See Also:

Async

delegate

public static <T> Future<T> delegate(T obj)

Returns a dummy Future object to be used to return a value in methods that are annotated with Async. Sample usage:

 @Async
 public Future<Integer> calculateAsync() {
     final Integer result = doHeavyCalculation();
     return Futures.delegate(result);
 }
 

You should not use the returned dummy object for any other purpose than returning it from a method which is annotated with Async.

API Note
The MethodInterceptor which handles the asynchronous invocations will extract the wrapped Object from this dummy Future and create an actual Future object by submitting the method invocation to an ExecutorService. Thus, the dummy Object created here will never leave the context of the method it is created in (if you do not manually leak it to the outside).

Type Parameters:

T - Type of the Object to return.

Parameters:

obj - The Object to return.

Returns:

The dummy object.

See Also:

Async