Avoid clearing of collections when closing StatefulPersistenceContext
Description
This is a very minor performance improvement; after having made most collections lazily initialized, there's no strong reason to actually clear() them when we could just null them out: a win-win both for performance and helping track down the garbage.
This is a very minor performance improvement; after having made most collections lazily initialized, there's no strong reason to actually clear() them when we could just null them out: a win-win both for performance and helping track down the garbage.