/** Looks up an entry. creating it if not found. */
public Element get(final Object key) throws LockTimeoutException {
try {
// if null will lock here
Element element = super.get(key);
if (element == null) {
// Value not cached - fetch it
Object value = factory.createEntry(key);
element = makeAndCheckElement(key, value);
put(element);
}
return element;
} catch (LockTimeoutException e) {
// do not release the lock, because you never acquired it
String message =
"Timeout after "
+ timeoutMillis
+ " waiting on another thread "
+ "to fetch object for cache entry \""
+ key
+ "\".";
throw new LockTimeoutException(message, e);
} catch (final Throwable throwable) {
// Could not fetch - Ditch the entry from the cache and rethrow
// release the lock you acquired
put(new Element(key, null));
throw new CacheException(
"Could not fetch object for cache entry with key \"" + key + "\".", throwable);
}
}
/**
* Refresh a single element.
*
* @param element the Element to refresh
* @param backingCache the underlying {@link Ehcache}.
* @param quiet whether to use putQuiet or not, if true replication will not occur
* @return the refreshed Element
* @throws Exception
* @since 1.6.1
*/
protected Element refreshElement(final Element element, Ehcache backingCache, boolean quiet)
throws Exception {
Object key = element.getObjectKey();
if (LOG.isLoggable(Level.FINE)) {
LOG.fine(getName() + ": refreshing element with key " + key);
}
final Element replacementElement;
if (factory instanceof UpdatingCacheEntryFactory) {
// update the value of the cloned Element in place
replacementElement = element;
((UpdatingCacheEntryFactory) factory)
.updateEntryValue(key, replacementElement.getObjectValue());
// put the updated element back into the backingCache, without updating stats
// It is not usually necessary to do this. We do this in case the element expired
// or idles out of the backingCache. In that case we hold a reference to it but the
// backingCache no longer does.
} else {
final Object value = factory.createEntry(key);
replacementElement = makeAndCheckElement(key, value);
}
if (quiet) {
backingCache.putQuiet(replacementElement);
} else {
backingCache.put(replacementElement);
}
return replacementElement;
}
