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Berkano-user defines a couple of interface for users, groups, permissions, membership management. Much like os-user does, but maybe with a more "modern" architecture.
All these are based on the principles of IOC, using CDI (constructor dependency injection). I'm personnaly personally using picocontainer, but I believe Spring or any other ioc container should be usable as well.
You will need to declare the implementations you want to use to your container.
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