Leitor de inteiros

static int leitor(BufferedReader br) throws NumberFormatException, IOException {
        int n;
        int resp = 0;
        int sinal = 1;
        while (true) {
            n = br.read();
            if (n >= '0' && n <= '9') break;
            if (n == '-') sinal = -1;
            if (n == '+') sinal = 1;
        }
        while (true) {
            resp = resp*10 + n-'0';
            n = br.read();
            if (n < '0' || n > '9') break;
        }
        return resp*sinal;
}