com.blacklocus.qs

Class RestartingQueueItemProvider<Q>

java.lang.Object

com.blacklocus.qs.RestartingQueueItemProvider<Q>

All Implemented Interfaces:

QueueItemProvider<Q>, java.lang.Iterable<java.util.Collection<Q>>, java.util.Iterator<java.util.Collection<Q>>

public class RestartingQueueItemProvider<Q>
extends java.lang.Object
implements QueueItemProvider<Q>

Constructor Summary

Constructors

Constructor and Description
RestartingQueueItemProvider(long restartDelayMs, com.google.common.base.Supplier<QueueItemProvider<Q>> quipSupplier)

Method Summary

Modifier and Type	Method and Description
boolean	hasNext()
java.util.Iterator<java.util.Collection<Q>>	iterator() Generally returns this.
java.util.Collection<Q>	next()
void	remove() A means to delete the message because it is done or should not be processed again.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

RestartingQueueItemProvider

public RestartingQueueItemProvider(long restartDelayMs,
                                   com.google.common.base.Supplier<QueueItemProvider<Q>> quipSupplier)

Parameters:

restartDelayMs - When a received QueueItemProvider ceases producing elements, how long the next call to next() will block in milliseconds before grabbing a new one from the supplier.

quipSupplier - that returns a working QueueItemProvider for each Supplier.get().

Method Detail

iterator

public java.util.Iterator<java.util.Collection<Q>> iterator()

Description copied from interface: QueueItemProvider

Generally returns this. QueueItemProviders are not generally reusable/resettable since the underlying message source will often not be reversible. Mashing the two interfaces together simplifies implementations a bit, and also supports any typical Iterable usage.

Specified by:

iterator in interface QueueItemProvider<Q>

Specified by:

iterator in interface java.lang.Iterable<java.util.Collection<Q>>

hasNext

public boolean hasNext()

Specified by:

hasNext in interface QueueItemProvider<Q>

Specified by:

hasNext in interface java.util.Iterator<java.util.Collection<Q>>

Returns:

true if the reading QueueReader should continue processing messages from this provider.

next

public java.util.Collection<Q> next()

Specified by:

next in interface QueueItemProvider<Q>

Specified by:

next in interface java.util.Iterator<java.util.Collection<Q>>

Returns:

the next batch of messages, or an empty collection if none were available. Should never return null. The reading QueueReader may sleep after receiving an empty batch depending on its configuration.

remove

public void remove()

Description copied from interface: QueueItemProvider

A means to delete the message because it is done or should not be processed again. If the provider does not care or has no such notion, should not throw an exception. An exception may be thrown if the provider does recognize remove semantics, but somehow failed in executing that intention.

Specified by:

remove in interface QueueItemProvider<Q>

Specified by:

remove in interface java.util.Iterator<java.util.Collection<Q>>