Can anyone throw some light on tools that can be used with NHibernate and which perform the below mentioned tasks:
And also provide information whether these tools are open source or licensed. Thanks
A similar question with some answers you might find useful is already on SO. http://stackoverflow.com/questions/41752/nhibernate-generators
As mentioned in that question's answers, fluent NHibernate is a good option. It just went RTM. You can find more info at http://fluentnhibernate.org/
One tool I've used that did a decent job was CodeSmith. It looked at the existing database and created the entities, mappings and configuration file. However, this is only to be used as a starting point as there are many tweaks you'll likely want to do to make it more usable and better performing. Things such as when to lazy load vs. eager load, creating subclasses or components. This tool really just mimics the database structure in your entities which is not always the best way to represent in code.
This is a licensed solution but it includes a fully functional demo you can use to gen your files initially. After that, you'll most likely just enhance just as you would your database.
Another is MyGeneration. Same thing, it'll get you 75% of the way there in most cases.
Just be cautious as to which version of NHibernate these tools are producing. They may be using an older version which may have some obsolete code.