Substract 1 from binary data. For example "00000011" - 1 -> "00000010"

Substract1FromBinary.java

private static String substract1(String binVal) {
    StringBuilder sb = new StringBuilder();
    int remainder = 0;
    for (int i = binVal.length() - 1; i >= 0; i--) {
        if (binVal.charAt(i) == '0') {
            sb.insert(0, '1');
            remainder = 1;
        } else if (i > 0) {
            sb.insert(0, '0');
            remainder = 0;
        }
        if (remainder == 0) {
            sb.insert(0, binVal.substring(0, i));
            break;
        }
    }

    return sb.toString();
}