I am trying to create a user id

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with java applications. This is not with Web based Java just the application part of it. I want to have a user enter their first last name and middle inital and the program create an Id for them with the first ketter of name and middle initial along with the first 3 letters of last name plus i want to have the unicode included with in the id. but i am trying to get it to where the user types in the user id that the program gives them to valadate it. But i am running in to trouble with the character parts of the program. could any one assist me with this