com.googlecode.objectify.cache

Class TriggerFuture<T>

java.lang.Object

com.googlecode.objectify.cache.TriggerFuture<T>

All Implemented Interfaces:

Future<T>

Direct Known Subclasses:

TriggerSuccessFuture

public abstract class TriggerFuture<T>
extends Object
implements Future<T>

A Future wrapper that executes an abstract method with the result at some point after the data becomes available. A "best effort" is made to ensure execution, but it may be left untriggered until the end of a request.

Notification will happen ONCE:

• After get() is called
• When the future is done and isDone() is called
• At the end of a request that has the AsyncCacheFilter enabled.

Use the AsyncCacheFilter for normal requests. For situations where a filter is not appropriate (ie, the remote api) be sure to call PendingFutures.completeAllPendingFutures() manually.

Note that if you are using this with Objectify, you probably want to use ObjectifyFilter.complete() rather than PendingFutures or AsyncCacheFilter static methods.

Author:

Jeff Schnitzer

Field Summary

Fields

Modifier and Type	Field and Description
protected Future<T>	raw Wrap the raw Future

Constructor Summary

Constructors

Constructor and Description
TriggerFuture(Future<T> raw) Wrap a normal Future

Method Summary

Modifier and Type	Method and Description
boolean	cancel(boolean mayInterruptIfRunning)
T	get()
T	get(long timeout, TimeUnit unit)
boolean	isCancelled()
boolean	isDone() This version also checks to see if we are done and we still need to call the trigger.
protected abstract void	trigger() This method will be called ONCE upon completion of the future, successful or not.

Methods inherited from class java.lang.Object

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

Field Detail

raw

protected Future<T> raw

Wrap the raw Future

Constructor Detail

TriggerFuture

public TriggerFuture(Future<T> raw)

Wrap a normal Future

Method Detail

trigger

protected abstract void trigger()

This method will be called ONCE upon completion of the future, successful or not. Beware that this.get() may throw an exception.

cancel

public boolean cancel(boolean mayInterruptIfRunning)

Specified by:

cancel in interface Future<T>

isCancelled

public boolean isCancelled()

Specified by:

isCancelled in interface Future<T>

isDone

public boolean isDone()

This version also checks to see if we are done and we still need to call the trigger. If so, it calls it.

Specified by:

isDone in interface Future<T>

See Also:

Future.isDone()

get

public T get()
      throws InterruptedException,
             ExecutionException

Specified by:

get in interface Future<T>

Throws:

InterruptedException

ExecutionException

get

public T get(long timeout,
             TimeUnit unit)
      throws InterruptedException,
             ExecutionException,
             TimeoutException

Specified by:

get in interface Future<T>

Throws:

InterruptedException

ExecutionException

TimeoutException