AbstractApplicationEventMulticaster populates ListenerRetriever cache in fully synchronized fashion

Issue: SPR-12545
This commit is contained in:
Juergen Hoeller 2014-12-22 15:46:58 +01:00
parent 4efe6a8a5c
commit 2b0ada95ce
1 changed files with 56 additions and 26 deletions

View File

@ -145,43 +145,73 @@ public abstract class AbstractApplicationEventMulticaster
Object source = event.getSource(); Object source = event.getSource();
Class<?> sourceType = (source != null ? source.getClass() : null); Class<?> sourceType = (source != null ? source.getClass() : null);
ListenerCacheKey cacheKey = new ListenerCacheKey(eventType, sourceType); ListenerCacheKey cacheKey = new ListenerCacheKey(eventType, sourceType);
// Quick check for existing entry on ConcurrentHashMap...
ListenerRetriever retriever = this.retrieverCache.get(cacheKey); ListenerRetriever retriever = this.retrieverCache.get(cacheKey);
if (retriever != null) { if (retriever != null) {
return retriever.getApplicationListeners(); return retriever.getApplicationListeners();
} }
else {
retriever = new ListenerRetriever(true); if (this.beanClassLoader == null ||
LinkedList<ApplicationListener> allListeners = new LinkedList<ApplicationListener>(); (ClassUtils.isCacheSafe(eventType, this.beanClassLoader) &&
Set<ApplicationListener> listeners; (sourceType == null || ClassUtils.isCacheSafe(sourceType, this.beanClassLoader)))) {
Set<String> listenerBeans; // Fully synchronized building and caching of a ListenerRetriever
synchronized (this.defaultRetriever) { synchronized (this.defaultRetriever) {
listeners = new LinkedHashSet<ApplicationListener>(this.defaultRetriever.applicationListeners); retriever = this.retrieverCache.get(cacheKey);
listenerBeans = new LinkedHashSet<String>(this.defaultRetriever.applicationListenerBeans); if (retriever != null) {
return retriever.getApplicationListeners();
}
retriever = new ListenerRetriever(true);
Collection<ApplicationListener> listeners = retrieveApplicationListeners(eventType, sourceType, retriever);
this.retrieverCache.put(cacheKey, retriever);
return listeners;
} }
for (ApplicationListener listener : listeners) { }
if (supportsEvent(listener, eventType, sourceType)) { else {
// No ListenerRetriever caching -> no synchronization necessary
return retrieveApplicationListeners(eventType, sourceType, null);
}
}
/**
* Actually retrieve the application listeners for the given event and source type.
* @param eventType the application event type
* @param sourceType the event source type
* @param retriever the ListenerRetriever, if supposed to populate one (for caching purposes)
* @return the pre-filtered list of application listeners for the given event and source type
*/
private Collection<ApplicationListener> retrieveApplicationListeners(
Class<? extends ApplicationEvent> eventType, Class<?> sourceType, ListenerRetriever retriever) {
LinkedList<ApplicationListener> allListeners = new LinkedList<ApplicationListener>();
Set<ApplicationListener> listeners;
Set<String> listenerBeans;
synchronized (this.defaultRetriever) {
listeners = new LinkedHashSet<ApplicationListener>(this.defaultRetriever.applicationListeners);
listenerBeans = new LinkedHashSet<String>(this.defaultRetriever.applicationListenerBeans);
}
for (ApplicationListener listener : listeners) {
if (supportsEvent(listener, eventType, sourceType)) {
if (retriever != null) {
retriever.applicationListeners.add(listener); retriever.applicationListeners.add(listener);
}
allListeners.add(listener);
}
}
if (!listenerBeans.isEmpty()) {
BeanFactory beanFactory = getBeanFactory();
for (String listenerBeanName : listenerBeans) {
ApplicationListener listener = beanFactory.getBean(listenerBeanName, ApplicationListener.class);
if (!allListeners.contains(listener) && supportsEvent(listener, eventType, sourceType)) {
if (retriever != null) {
retriever.applicationListenerBeans.add(listenerBeanName);
}
allListeners.add(listener); allListeners.add(listener);
} }
} }
if (!listenerBeans.isEmpty()) {
BeanFactory beanFactory = getBeanFactory();
for (String listenerBeanName : listenerBeans) {
ApplicationListener listener = beanFactory.getBean(listenerBeanName, ApplicationListener.class);
if (!allListeners.contains(listener) && supportsEvent(listener, eventType, sourceType)) {
retriever.applicationListenerBeans.add(listenerBeanName);
allListeners.add(listener);
}
}
}
OrderComparator.sort(allListeners);
if (this.beanClassLoader == null ||
(ClassUtils.isCacheSafe(eventType, this.beanClassLoader) &&
(sourceType == null || ClassUtils.isCacheSafe(sourceType, this.beanClassLoader)))) {
this.retrieverCache.put(cacheKey, retriever);
}
return allListeners;
} }
OrderComparator.sort(allListeners);
return allListeners;
} }
/** /**