private MessageDigest md5;

    private byte[] ipad = new byte[BLOCK_LENGTH];

    private byte[] opad = new byte[BLOCK_LENGTH];

    /**
     * Creates an HMACT64 instance which uses the given secret key material.
     *
     * @param key The key material to use in hashing.
     */
    public HMACT64(byte[] key) {
        super("HMACT64");
        int length = Math.min(key.length, BLOCK_LENGTH);

    private MessageDigest md5;

    private byte[] ipad = new byte[BLOCK_LENGTH];

    private byte[] opad = new byte[BLOCK_LENGTH];


    /**
     * Creates an HMACT64 instance which uses the given secret key material.
     *
     * @param key
     *            The key material to use in hashing.
     */
    public HMACT64 ( byte[] key ) {
        super("HMACT64");