Class EventDispatcher<K,V>

java.lang.Object

com.github.benmanes.caffeine.jcache.event.EventDispatcher<K,V>

public final class EventDispatcher<K,V>
extends Object

A dispatcher that publishes cache events to listeners for asynchronous execution.

A CacheEntryListener is required to receive events in the order of the actions being performed on the associated key. This implementation supports this through an actor-like model by using a dispatch queue per listener. A listener is never executed in parallel on different events, but may be executed sequentially on different threads. Batch processing of the dispatch queue is not presently supported.

Some listeners may be configured as synchronous, meaning that the publishing thread should wait until the listener has processed the event. The calling thread should publish within an atomic block that mutates the entry, and complete the operation by calling awaitSynchronous() or ignoreSynchronous().

Field Summary

Fields

Modifier and Type	Field	Description
(package private) final Map<Registration<K,V>, CompletableFuture<Void>>	dispatchQueues
(package private) final Executor	executor
(package private) static final Logger	logger
(package private) static final ThreadLocal<List<CompletableFuture<Void>>>	pending

Constructor Summary

Constructors

Constructor	Description
EventDispatcher(Executor executor)

Method Summary

Modifier and Type	Method	Description
void	awaitSynchronous()	Blocks until all of the synchronous listeners have finished processing the events this thread published.
void	deregister(javax.cache.configuration.CacheEntryListenerConfiguration<K,V> configuration)	Deregisters a cache entry listener based on the supplied configuration.
void	ignoreSynchronous()	Ignores and clears the queued futures to the synchronous listeners that are processing events this thread published.
private void	publish(javax.cache.Cache<K,V> cache, javax.cache.event.EventType eventType, K key, boolean hasOldValue, @Nullable V oldValue, @Nullable V newValue, boolean quiet)	Broadcasts the event to all of the interested listener's dispatch queues.
void	publishCreated(javax.cache.Cache<K,V> cache, K key, V value)	Publishes a creation event for the entry to all of the interested listeners.
void	publishExpired(javax.cache.Cache<K,V> cache, K key, V value)	Publishes a expire event for the entry to all of the interested listeners.
void	publishExpiredQuietly(javax.cache.Cache<K,V> cache, K key, V value)	Publishes a expire event for the entry to all of the interested listeners.
void	publishRemoved(javax.cache.Cache<K,V> cache, K key, V value)	Publishes a remove event for the entry to all of the interested listeners.
void	publishRemovedQuietly(javax.cache.Cache<K,V> cache, K key, V value)	Publishes a remove event for the entry to all of the interested listeners.
void	publishUpdated(javax.cache.Cache<K,V> cache, K key, V oldValue, V newValue)	Publishes a update event for the entry to all of the interested listeners.
void	register(javax.cache.configuration.CacheEntryListenerConfiguration<K,V> configuration)	Registers a cache entry listener based on the supplied configuration.
Set<Registration<K,V>>	registrations()	Returns the cache entry listener registrations.

Methods inherited from class Object

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

Field Details

logger

static final Logger logger

pending

static final ThreadLocal<List<CompletableFuture<Void>>> pending

executor

final Executor executor

dispatchQueues

final Map<Registration<K,V>, CompletableFuture<Void>> dispatchQueues

Constructor Details

EventDispatcher

public EventDispatcher(Executor executor)

Method Details

registrations

public Set<Registration<K,V>> registrations()

Returns the cache entry listener registrations.

register

public void register(javax.cache.configuration.CacheEntryListenerConfiguration<K,V> configuration)

Registers a cache entry listener based on the supplied configuration.

Parameters:

configuration - the listener's configuration.

deregister

public void deregister(javax.cache.configuration.CacheEntryListenerConfiguration<K,V> configuration)

Deregisters a cache entry listener based on the supplied configuration.

Parameters:

configuration - the listener's configuration.

publishCreated

public void publishCreated(javax.cache.Cache<K,V> cache,
 K key,
 V value)

Publishes a creation event for the entry to all of the interested listeners.

Parameters:

cache - the cache where the entry was created

key - the entry's key

value - the entry's value

publishUpdated

public void publishUpdated(javax.cache.Cache<K,V> cache,
 K key,
 V oldValue,
 V newValue)

Publishes a update event for the entry to all of the interested listeners.

Parameters:

cache - the cache where the entry was updated

key - the entry's key

oldValue - the entry's old value

newValue - the entry's new value

publishRemoved

public void publishRemoved(javax.cache.Cache<K,V> cache,
 K key,
 V value)

Publishes a remove event for the entry to all of the interested listeners.

Parameters:

cache - the cache where the entry was removed

key - the entry's key

value - the entry's value

publishRemovedQuietly

public void publishRemovedQuietly(javax.cache.Cache<K,V> cache,
 K key,
 V value)

Publishes a remove event for the entry to all of the interested listeners. This method does not register the synchronous listener's future with awaitSynchronous().

Parameters:

cache - the cache where the entry was removed

key - the entry's key

value - the entry's value

publishExpired

public void publishExpired(javax.cache.Cache<K,V> cache,
 K key,
 V value)

Publishes a expire event for the entry to all of the interested listeners.

Parameters:

cache - the cache where the entry expired

key - the entry's key

value - the entry's value

publishExpiredQuietly

public void publishExpiredQuietly(javax.cache.Cache<K,V> cache,
 K key,
 V value)

Publishes a expire event for the entry to all of the interested listeners. This method does not register the synchronous listener's future with awaitSynchronous().

Parameters:

cache - the cache where the entry expired

key - the entry's key

value - the entry's value

awaitSynchronous

public void awaitSynchronous()

Blocks until all of the synchronous listeners have finished processing the events this thread published.

ignoreSynchronous

public void ignoreSynchronous()

Ignores and clears the queued futures to the synchronous listeners that are processing events this thread published.

publish

private void publish(javax.cache.Cache<K,V> cache,
 javax.cache.event.EventType eventType,
 K key,
 boolean hasOldValue,
 @Nullable V oldValue,
 @Nullable V newValue,
 boolean quiet)

Broadcasts the event to all of the interested listener's dispatch queues.