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

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