Package org.apache.drill.common.concurrent

Class AbstractCheckedFuture<T,E extends Exception>

java.lang.Object

com.google.common.collect.ForwardingObject

com.google.common.util.concurrent.ForwardingFuture<T>

com.google.common.util.concurrent.ForwardingListenableFuture<T>

com.google.common.util.concurrent.ForwardingListenableFuture.SimpleForwardingListenableFuture<T>

org.apache.drill.common.concurrent.AbstractCheckedFuture<T,E>

All Implemented Interfaces:

com.google.common.util.concurrent.ListenableFuture<T>, Future<T>, CheckedFuture<T,E>

Direct Known Subclasses:

RpcCheckedFuture

public abstract class AbstractCheckedFuture<T,E extends Exception>
extends com.google.common.util.concurrent.ForwardingListenableFuture.SimpleForwardingListenableFuture<T>
implements CheckedFuture<T,E>

A delegating wrapper around a ListenableFuture that adds support for the checkedGet() and checkedGet(long, TimeUnit) methods. This class is moved from Guava, since there it was deleted.

Nested Class Summary

Nested classes/interfaces inherited from class com.google.common.util.concurrent.ForwardingListenableFuture

com.google.common.util.concurrent.ForwardingListenableFuture.SimpleForwardingListenableFuture<V>

Nested classes/interfaces inherited from class com.google.common.util.concurrent.ForwardingFuture

com.google.common.util.concurrent.ForwardingFuture.SimpleForwardingFuture<V>

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractCheckedFuture(com.google.common.util.concurrent.ListenableFuture<T> delegate)

Method Summary

Modifier and Type	Method	Description
T	checkedGet()	Exception checking version of Future.get() that will translate InterruptedException, CancellationException and ExecutionException into application-specific exceptions.
T	checkedGet(long timeout, TimeUnit unit)	Exception checking version of Future.get(long, TimeUnit) that will translate InterruptedException, CancellationException and ExecutionException into application-specific exceptions.
protected abstract E	mapException(Exception e)	Translates from an InterruptedException, CancellationException or ExecutionException thrown by get to an exception of type X to be thrown by checkedGet.

Methods inherited from class com.google.common.util.concurrent.ForwardingListenableFuture.SimpleForwardingListenableFuture

delegate

Methods inherited from class com.google.common.util.concurrent.ForwardingListenableFuture

addListener

Methods inherited from class com.google.common.util.concurrent.ForwardingFuture

cancel, get, get, isCancelled, isDone

Methods inherited from class com.google.common.collect.ForwardingObject

toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.concurrent.Future

cancel, get, get, isCancelled, isDone

Methods inherited from interface com.google.common.util.concurrent.ListenableFuture

addListener

Constructor Details

AbstractCheckedFuture

protected AbstractCheckedFuture(com.google.common.util.concurrent.ListenableFuture<T> delegate)

Method Details

mapException

protected abstract E mapException(Exception e)

Translates from an InterruptedException, CancellationException or ExecutionException thrown by get to an exception of type X to be thrown by checkedGet. Subclasses must implement this method.

If e is an InterruptedException, the calling checkedGet method has already restored the interrupt after catching the exception. If an implementation of mapException(Exception) wishes to swallow the interrupt, it can do so by calling Thread.interrupted().

Subclasses may choose to throw, rather than return, a subclass of RuntimeException to allow creating a CheckedFuture that throws both checked and unchecked exceptions.

checkedGet

public T checkedGet()
             throws E

Exception checking version of Future.get() that will translate InterruptedException, CancellationException and ExecutionException into application-specific exceptions.

Specified by:

checkedGet in interface CheckedFuture<T,E extends Exception>

Returns:

the result of executing the future.

Throws:

E - on interruption, cancellation or execution exceptions.

checkedGet

public T checkedGet(long timeout,
 TimeUnit unit)
             throws TimeoutException,
E

Exception checking version of Future.get(long, TimeUnit) that will translate InterruptedException, CancellationException and ExecutionException into application-specific exceptions. On timeout this method throws a normal TimeoutException.

Specified by:

checkedGet in interface CheckedFuture<T,E extends Exception>

Returns:

the result of executing the future.

Throws:

TimeoutException - if retrieving the result timed out.

E - on interruption, cancellation or execution exceptions.