Description Sahoo 2010-11-25 04:40:00 EST

Build Identifier: 2.2.0.v20101117-r8503

DefaultPersistenceProviderResolver has field like this:

        private volatile WeakHashMap<ClassLoader, List<PersistenceProvider>> providers = new WeakHashMap<ClassLoader, List<PersistenceProvider>>();
        ...
                        Collection<ProviderName> providerNames = getProviderNames(loader);
                loadedProviders = new ArrayList<PersistenceProvider>();
        ...
A WeakHashMap is used to avoid permanently holding a reference to user's class loader, but look at the value being stored there: it's an ArrayList<PersistenceProvider>, which means if the provider is loaded by user's class loader, it can never be garbage collected until the cache is cleared. Does anyone clear this cache? I don't think so. Why not change it to:
WeakHashMap<ClassLoader, List<String>>, where in the value, we store discovered provider class names as opposed to provider instances. When a provider is required, one can then do ClassLoader.loadClass(providerName).newInstance().

Reproducible: Always