Time Regex expression

[Duc Ta]

Hey guys,
Can anyone help me to write regex to match with String below:

24/02/2019 10:46

for mat date time is DD/MM/YYYY HH:MM

This is urgent task of mine. I have searched it but no expected result.
Please help me

[Liutauras Vilda]

I think there are some results which do what you need, at least seem to be very close --> here

[Stephan van Hulst]

Do you just want to match the string or do you want to parse it?

If you want to match it, read the documentation of the Pattern class.

If you want to parse it, read the documentation of the DateTimeFormatter class.

If you're stuck, then tell us what you've tried and what part of the documentation you don't understand.

[fred rosenberger]

you need to be more specific.  something like this would match that string:

.*

if you want to get more precise, you could do it on digits and literals, i.e.

\d\d/\d\d....etc

if you then further want to validate the characters before the first slash resolve to a value less than 32, or are valid against the month specified (i.e. no "30" if the month is "02"), then you need more than just a regex.

[Tim Holloway]

I'm with Stephan.

Unless you have to 100% match that pattern, using the DateTimeFormatter is a much more useful solution. If the input matches the date/time pattern, you get a free conversion to a timestamp as a side effect. If it fails to match, you get an Exception.

[fred rosenberger]

that sort of brings the question around do "do you need to know how to write a regex" or "do you need to match this string and/or do something to it...".  The details matter when it comes to getting the best possible help.

[Paul Clapham]

It's pretty hard to write a regex which will reject February 29 except for a leap year -- but then that wasn't exactly one of the stated requirements.

[Campbell Ritchie]

Paul Clapham wrote:. . . a regex which will reject February 29 except for a leap year . . . .

That sounds like something outwith the scope of a regular grammar. But don't worry; I think LocalDate will throw lots of exceptions if you try to tell it today is 29th February 2019.

[Paul Clapham]

Campbell Ritchie wrote:I think LocalDate will throw lots of exceptions if you try to tell it today is 29th February 2019.

So do I. That's why I think you should use LocalDate rather than a regex.