RegEx to allow hyphens (maximum 3) in a string but do not count it in length in JAVA-CodePudding

My requirement is to limit the length of the input string to 11 which can be alphanumeric with hyphens. The maximum allowable hyphens are 3 and hyphens shouldn’t be considered in length. Another requirement is to not allow more than 5 continuous repetitive digits.

My Regex is ^(?!.*([0-9])\\1{5})(?=.*([-]){0,3})[a-zA-Z0-9]{11}$

Any help is highly appreciated.

CodePudding user response：

Well, one way is:

^(?!.*?(\d)\1{5})(?=(?:[a-z0-9]-?){11}$)[a-z0-9] (?:-[a-z0-9] ){0,3}$

See an online demo

^ - Start-line anchor;
(?!.*?(\d)\1{5}) - Negative lookahead to assert input has no digit that is repeated 6 times;
(?=(?:[a-z0-9]-?){11}$) - Positive lookahead to assert input has 11 alphanumeric characters (with optional hyphens);
[a-z0-9] (?:-[a-z0-9] ){0,3} - 1 Alnum chars followed by a non-capture group (0-3 times) to allow for hyphens;
$ - End-line anchor.

Note that it would not allow for hyphens to be at either: start, end or consecutive. Further note that I used the case-insensitive flag.