1. A method performed in a data processing system for mapping user roles for a user registry migration, the method comprising: detecting a role mapping file comprising a set of rules, wherein each rule defines a set of conditions for assigning a new role; conjoining the set of conditions to form a set of migration rules for the new role; retrieving a current role of at least one user from a list of users in a user registry; applying at least one migration rule from the set of migration rules to the current role of the at least one user; determining if the current role of the at least one user satisfies the at least one migration rule; assigning the new role to the at least one user if the current role of the at least one user satisfies the at least one migration rule; and updating the user registry with the new role for the at least one user.