org.apache.hadoop.util.functional

Class CommonCallableSupplier<T>

java.lang.Object

org.apache.hadoop.util.functional.CommonCallableSupplier<T>

Type Parameters:

T - return type.

All Implemented Interfaces:

Supplier

public final class CommonCallableSupplier<T>
extends Object
implements Supplier

A bridge from Callable to Supplier; catching exceptions raised by the callable and wrapping them as appropriate.

Constructor Summary

Constructors

Constructor and Description
CommonCallableSupplier(Callable<T> call) Create.

Method Summary

Modifier and Type	Method and Description
Object	get()
static void	maybeAwaitCompletion(CompletableFuture<Void> future) Block awaiting completion for any non-null future passed in; No-op if a null arg was supplied.
static <T> CompletableFuture<T>	submit(Executor executor, Callable<T> call) Submit a callable into a completable future.
static <T> void	waitForCompletion(CompletableFuture<T> future) Wait for a single of future to complete, extracting IOEs afterwards.
static <T> void	waitForCompletion(List<CompletableFuture<T>> futures) Wait for a list of futures to complete.
static <T> void	waitForCompletionIgnoringExceptions(CompletableFuture<T> future) Wait for a single of future to complete, ignoring exceptions raised.

Methods inherited from class java.lang.Object

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

Constructor Detail

CommonCallableSupplier

public CommonCallableSupplier(Callable<T> call)

Create.

Parameters:

call - call to invoke.

Method Detail

get

public Object get()

Specified by:

get in interface Supplier

submit

public static <T> CompletableFuture<T> submit(Executor executor,
                                              Callable<T> call)

Submit a callable into a completable future. RTEs are rethrown. Non RTEs are caught and wrapped; IOExceptions to RuntimeIOException instances.

Type Parameters:

T - type

Parameters:

executor - executor.

call - call to invoke

Returns:

the future to wait for

waitForCompletion

public static <T> void waitForCompletion(List<CompletableFuture<T>> futures)
                                  throws IOException

Wait for a list of futures to complete. If the list is empty, return immediately.

Parameters:

futures - list of futures.

Throws:

IOException - if one of the called futures raised an IOE.

RuntimeException - if one of the futures raised one.

waitForCompletion

public static <T> void waitForCompletion(CompletableFuture<T> future)
                                  throws IOException

Wait for a single of future to complete, extracting IOEs afterwards.

Parameters:

future - future to wait for.

Throws:

IOException - if one of the called futures raised an IOE.

RuntimeException - if one of the futures raised one.

waitForCompletionIgnoringExceptions

public static <T> void waitForCompletionIgnoringExceptions(@Nullable
                                                           CompletableFuture<T> future)

Wait for a single of future to complete, ignoring exceptions raised.

Parameters:

future - future to wait for.

maybeAwaitCompletion

public static void maybeAwaitCompletion(@Nullable
                                        CompletableFuture<Void> future)
                                 throws IOException

Block awaiting completion for any non-null future passed in; No-op if a null arg was supplied.

Parameters:

future - future

Throws:

IOException - if one of the called futures raised an IOE.

RuntimeException - if one of the futures raised one.