com.databasesandlife.util

Class Future<T>

java.lang.Object

com.databasesandlife.util.Future<T>

Direct Known Subclasses:

Future.IterableFuture

public abstract class Future<T>
extends Object

A future is the response of a calculation which is done in the background (in a thread).

A future has the method get() which waits for the calculation to complete, and returns the result. The client must create a subclass and implement the method populate() which will be run in the thread.

The reason for the creation of this class is the JVM-supplied Future object seemed too complex.

Author:

This source is copyright Adrian Smith and licensed under the LGPL 3.

See Also:

Project on GitHub

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Future.FutureComputationTimedOutException
static class	Future.FuturePopulationException An exception occurred during the population of this future
static class	Future.IterableFuture<I> An iterable whose values are computed in the background.

Constructor Summary

Constructors

Constructor and Description
Future()

Method Summary

Modifier and Type	Method and Description
T	get() Returns the object, waiting for its computation to be completed if necessary.
T	getOrTimeoutAfterSeconds(float seconds) Same as get() but times out after 'seconds' seconds.
protected String	getThreadName()
protected abstract T	populate() Calculate the result and return it.

Methods inherited from class java.lang.Object

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

Constructor Detail

Future

public Future()

Method Detail

populate

protected abstract T populate()

Calculate the result and return it. Must not return null.

getThreadName

protected String getThreadName()

getOrTimeoutAfterSeconds

public T getOrTimeoutAfterSeconds(float seconds)
                           throws Future.FutureComputationTimedOutException,
                                  Future.FuturePopulationException

Same as get() but times out after 'seconds' seconds.

Throws:

Future.FutureComputationTimedOutException

Future.FuturePopulationException

get

public T get()

Returns the object, waiting for its computation to be completed if necessary.