HOw to construct page, workset, layout and roles programatically

My requirement is something like this .

Using content administration I will create a role(Role1) and iviews . I assign all the iviews to this role( role1 ) then after changing the roles' property "Entry point" to Yes. I assign this to a user1 . once user logs in he will see these Iviews which are defined under the role1. This can be achieved using Content Administration

-> portel content.

How to constrcut this programatically.

Some code snippets will be very helpful for me

thanks

pk