org.jboss.aerogear.unifiedpush.message.cache

Class AbstractServiceCache<T>

java.lang.Object

org.jboss.aerogear.unifiedpush.message.cache.AbstractServiceCache<T>

Direct Known Subclasses:

ApnsServiceCache

public abstract class AbstractServiceCache<T>
extends Object

Abstract cache holds queue of services with upper-bound limit of created instances. Cache allows to return freed up services to the queue or free a slot for creating new services up to a limit.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	AbstractServiceCache.ServiceConstructor<T>

Constructor Summary

Constructors

Constructor and Description
AbstractServiceCache(int instanceLimit, long instanceAcquiringTimeoutInMillis) Creates new cache

Method Summary

Methods

Modifier and Type	Method and Description
T	dequeue(String pushMessageInformationId, String variantID) Dequeues the service instance if there is one available, otherwise returns null
T	dequeueOrCreateNewService(String pushMessageInformationId, String variantID, AbstractServiceCache.ServiceConstructor<T> constructor) Cache returns a service for given parameters or uses service constructor to instantiate new service.
void	freeUpSlot(String pushMessageInformationId, String variantID) Allows to free up a counter of created services and thus allowing waiting consumers to create new services within the limits.
void	queueFreedUpService(String pushMessageInformationId, String variantID, T service) Allows to queue used and freed up service into cache so that can be reused by another consumer.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractServiceCache

public AbstractServiceCache(int instanceLimit,
                    long instanceAcquiringTimeoutInMillis)

Creates new cache

Parameters:

instanceLimit - how many instances can be created

instanceAcquiringTimeoutInMillis - what is a timeout before the cache can return null

Method Detail

dequeueOrCreateNewService

public T dequeueOrCreateNewService(String pushMessageInformationId,
                          String variantID,
                          AbstractServiceCache.ServiceConstructor<T> constructor)

Cache returns a service for given parameters or uses service constructor to instantiate new service. Number of created or queued services is limited up to configured instanceLimit. The service blocks until a service is available or configured timeout. In case the service is not available when times out, cache returns null.

Parameters:

pushMessageInformationId - the push message id

variant - the variant

constructor - the service constructor

Returns:

the service instance; or null in case too much services were created and no services are queued for reuse

dequeue

public T dequeue(String pushMessageInformationId,
        String variantID)

Dequeues the service instance if there is one available, otherwise returns null

Parameters:

pushMessageInformationId - the push message id

variant - the variant

Returns:

the service instance or null if no instance is queued

queueFreedUpService

public void queueFreedUpService(String pushMessageInformationId,
                       String variantID,
                       T service)

Allows to queue used and freed up service into cache so that can be reused by another consumer.

Parameters:

pushMessageInformationId - the push message

variant - the variant

service - the used and freed up service

freeUpSlot

public void freeUpSlot(String pushMessageInformationId,
              String variantID)

Allows to free up a counter of created services and thus allowing waiting consumers to create new services within the limits. Freed up service is a service that died, disconnected or similar and can no longer be used.

Parameters:

pushMessageInformationId - the push message

variant - the variant