HMAC-SHA256 Algorithm for signature calculation

Question

I am trying to create a signature using the HMAC-SHA256 algorithm and this is my code. I am using US ASCII encoding.

final Charset asciiCs = Charset.forName(         


        

Answer 1

The answer that you got there is correct. One minor thing in the code above, you need to init(key) before you can call doFinal()

    final Charset charSet = Charset.forName("US-ASCII");
    final Mac sha256_HMAC = Mac.getInstance("HmacSHA256");

    final SecretKeySpec secret_key = new javax.crypto.spec.SecretKeySpec(charSet.encode("key").array(), "HmacSHA256");
    try {
        sha256_HMAC.init(secret_key);
    } catch (InvalidKeyException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    ...