Java program for four square encryption Its a four square encryption program with two input keys. Enter the keys and then enter whether encrypt or decrypt then enter the plain text or cipher text respectively. I used a different 6x6 format which includes all letters and numbers. a b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 8 9 0