How to write a JAVA random ID method WITHOUT using ASCII code

BONUS // returns a random ID (length =7 ). // do not use ASCII value(code) public String nextID() \{ // use method 1 . . return ID; ID Rule: 1) ID must be 8 characters in length. 2) ID must have lower-case AND upper case. 3) ID must start with a letter like [a-z A-Z] 4) Usernames must have at least one number like [0-9] 5) Usernames must have at least one of any special characters