New to Java

Hi everyone,

I have a binary String representing a character - for example, character f = 01100110
I also have a cipher String represented as 0's and 1's that could be upto 128 in length = 01011101010111000101000010001001001111101111011 etc etc.

I want to use the cipher to encrypt the character and the reverse.

I have attempted to use BigInteger to XOR both and to decrypt do the reverse except occasionally I get a number format exception because the binary string is too large (I think).

Here is the code:

    public String encrypt(String plain, String secret) {
    
        BigInteger bi = new BigInteger(plain);
        BigInteger bii = new BigInteger(secret, 2);
        BigInteger res = bi.xor(bii);
        return res.toString();    
    }
   
    public String decrypt(String encrypted, String secret) {

        BigInteger bi = new BigInteger(encrypted);
        BigInteger bii = new BigInteger(secret, 2);
        BigInteger res = bii.xor(bi);
        String str = res.toString();
        long val = (long) Long.parseLong(str, 2);
        Character c = new Character((char) val);
        String out = (String) c.toString();
        return out;        
    }

Also the encrypt method is obvious as the bigInteger is the same value except for the last few digits.

Is there any way I can encrypt /decrypt so it is not so obvious and no number format errors?

Thanx in advance