SafeNamedCache was explicitly released error

Question

Hi there, we are using Coherence 3.7.1.1 within Weblogic 11.1.1.6.0
We have some Java code deployed on the server:
public Session create(User user) {
NamedCache sessionCache = CacheFactory.getCache(SESSION_CACHE_NAME);
Session session = new Session(user);
sessionCache.put(session.getSessionId(), session, getConfig().getSessionTTL());
CacheFactory.releaseCache(sessionCache);
return session;
Every now and again it fails on the sessionCache.put method (line 71) with SafeNamedCache was explicitly released.
Error stack:
SafeNamedCache was explicitly released</message> <ns2:stackTrace>
<ns2:frame class="com.tangosol.coherence.component.util.SafeNamedCache" file="SafeNamedCache.CDB" line="23" method="ensureRunningNamedCache"/>
<ns2:frame class="com.tangosol.coherence.component.util.SafeNamedCache" file="SafeNamedCache.CDB" line="1" method="getRunningNamedCache"/>
<ns2:frame class="com.tangosol.coherence.component.util.SafeNamedCache" file="SafeNamedCache.CDB" line="1" method="put"/>
<ns2:frame class="mywes.security.sessions.impl.SessionDao" file="SessionDao.java" line="71" method="create"/>
Any ideas why this would be happening? And what can be done to stop this from happening?
Regards
Robert

Answer 1

Hi,
I assume your code is running inside some sort of Web Application inside WebLogic and is therefore multi-threaded - that is, multiple threads could call this code at the same time. In that case it may be that something like this happens...
Thread 1: NamedCache sessionCache = CacheFactory.getCache(SESSION_CACHE_NAME);
Thread 2: NamedCache sessionCache = CacheFactory.getCache(SESSION_CACHE_NAME);
Thread 1: Session session = new Session(user);
Thread 2: Session session = new Session(user);
Thread 2: sessionCache.put(session.getSessionId(), session, getConfig().getSessionTTL());
Thread 2: CacheFactory.releaseCache(sessionCache);
Thread 1: sessionCache.put(session.getSessionId(), session, getConfig().getSessionTTL());
As the cache factory and cache are singletons inside Coherence if Thread 2 has called releaseCache before Thread 1 does the put then the put will fail as the cache has been released.
JK