This Java program decrypts an encoded message using a key. It takes an encoded byte array, decodes it from Base64, then decrypts it by XORing each byte with the bytes of the key "vonholtu.neil" repeatedly. Finally, it prints the decrypted message as a string.

1. //Author: Neil VonHoltum
import java.util.Base64;
public class Decrypt {
public static void main(String[] args) {
byte[] messagebytes = Base64.getDecoder().decode
("DUgdHQwPEQZdSUVTTFEIHA0OGFNZDkkGBgAaCg8PGglTVRROQgwfAgo" +
"LBQoIU1kOSQAPChkdGhtITE5VCQcLCh4TCwcKAwlTWQ5JBAoEHwoYDQIJG" +
"gEJTl9JSwMBAgcMBxERCUJFTh4XDQwBGx9TVRROQhoNEApJRE9LEhpBS" +
"UVTTFEYBwZOSwk="),
keybytes = "vonholtu.neil".getBytes();
int i = 0;
while(i < 130){
for(int t = 0; t < 13; t++, i++){
messagebytes[i] = (byte)(messagebytes[i] ^ keybytes[t]);
}
}
for(int t = 0; i < 137; i++, t++){
messagebytes[i] = (byte)(messagebytes[i] ^ keybytes[t]);
}
System.out.println(new String(messagebytes));
}
}