What's wrong with my MM/DD/YYYY regex in JENKINS

Question

I need to validate the date format in MM/DD/YYYY. Null is a valid too in my scenario. This is my regex [0-9]{2}\/[0-9]{2}\/[0-9]{4}$ |

Below image shows the job configuration with my regex

ERROR

Answer 1

I modified the original to this:

^(?:(?:(?:0?[13578]|1[02]|(?:Jan|Mar|May|Jul|Aug|Oct|Dec))(\/|-|\.)31)\1|(?:(?:0?[1,3-9]|1[0-2]|(?:Jan|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec))(\/|-|\.)(?:29|30)\2))(?:(?:1[6-9]|[2-9]\d)?\d{2})$|^(?:(?:0?2|(?:Feb))(\/|-|\.)(?:29)\3(?:(?:(?:1[6-9]|[2-9]\d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00))))$|^(?:(?:0?[1-9]|(?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep))|(?:1[0-2]|(?:Oct|Nov|Dec)))(\/|-|\.)(?:0?[1-9]|1\d|2[0-8])\4(?:(?:1[6-9]|[2-9]\d)?\d{2})$

Test the regex here

Answer 2

I would do the initial validation with

^[0-9]{2}\/[0-9]{2}\/[0-9]{4}$

I have added ^ to indicate the start of the string and I have removed | (it is union operator, OR) from the end of your original regex. I tested it here .

Answer 3

You have space after the $ sign, that's why you input doesn't match.

[0-9]{2}\/[0-9]{2}\/[0-9]{4}$ |
//                    here __^

Remove it ( [0-9]{2}\/[0-9]{2}\/[0-9]{4}$ ) and, if you want to accept empty string, add empty string with a group, and add beginning of string anchor:

^([0-9]{2}\/[0-9]{2}\/[0-9]{4}|)$

or, better, make the group optional

^([0-9]{2}\/[0-9]{2}\/[0-9]{4})?$

Demo & explanation