mockedCrypto.when(Crypto::getMD5).thenReturn(mockMd5);
            byte[] innerDigest = "inner_digest".getBytes();
            byte[] finalDigest = "final_digest".getBytes();

            when(mockMd5.digest()).thenReturn(innerDigest);
            when(mockMd5.digest(any(byte[].class))).thenReturn(finalDigest);

            HMACT64 hmac = new HMACT64(TEST_KEY);