Question

I tried like this it is not working, but not works for value 005959 format HHMMSS

if(Pattern.matches("^([0-23])([0-59])([0-59])$", value))
{
    SimpleDateFormat dformat = new SimpleDateFormat("HHMMSS");
    dformat.setLenient(false);
    dformat.parse(value);
    return true;
}

Answer 1

You can’t do numeric ranges like that. To validate 1-24 (what’s wrong with 00 by the way? and since when was 60 valid in the other positions?) you’d need to do it digit by digit like this:

(0[1-9]|1[0-9]|2[0-4])

That is, if the first digit is 0 then 1-9 must follow; if 1 then any can follow; if 2 then 0-4 must follow. But why use Regex for this anyway? In full:

^(0[1-9]|1[0-9]|2[0-4])(0[1-9]|[1-5][0-9]|60)(0[1-9]|[1-5][0-9]|60)$

But still, check comments on 0 and 60 values…