We have an application that handles parsing of a file from 1 format to another. It uses hibernate to access the database and retrieve the parameters for its parsing. Basically whenever a user saves a file in our file folder the application will automatically retrieve that file and parse it to the corresponding file format. Lately we've began encountering out of memory exception with our application and using the dump file it produces after the server breakdown we consulted the IBM people for help and this was there findings.
Leak suspect 
The leak suspect root org/hibernate/impl/SessionFactoryObjectFactory is responsible for 65% of the total Java heap. It has 1,406 references to the type: java/util/HashMap$Entry. Please review the object org/hibernate/impl/SessionFactoryObjectFactory to assess how much Java heap is required by the object.
|-------java/util/HashMap$Entry, object0x3ef69310, reaches: 9,612,229 bytes
|-------java/util/HashMap$Entry, object have grown by 1,406 instances
The leak suspect is a class of type: org/hibernate/impl/SessionFactoryObjectFactory
The leak suspect size is: 662MB
The object the leak suspect is holding that contains leaking objects is a class of type: java/util/HashMap$Entry
The object the leak suspect is holding that contains leaking objects has a size of: 662MB
The object that is suspected to be leaking is a class of type: java/util/HashMap$Entry
The object that is suspected to be leaking has a size of: 10MB
The object that is suspected to be leaking occurs: 1,406 times.
We have no idea how can Hibernate hash map will cause this much of heap size consumption. Anyone help please.... ^_^
Why do you think this is a leak? Is it exhibiting leak behaviour? The sesson factory is pretty central to everything Hibernate does and I'm not aware of memory leaks in it. There is certainly nothing in the Hibernate JIRA.
My guess is this is something about how you use Hibernate not Hibernate itself. Can you post your code?