do {
            char ch = arr[si];

            switch (state) {
                case 0:
                    if (ch == ':') {
                        proto = str.substring(mark, si);
                        mark = si + 1;
                        state = 1;
                    }
                    break;
                case 1:
                    if (ch == '\\') {
                        mark = si + 1;