CODEWITHSUNDEEP
javaregex
user1016950
user1016950

Reputation: 187

Java Regex for username

I'm looking for a regex in Java, java.util.regex, to accept only letters ’, -, and . and a range of Unicode characters such as umlauts, eszett, diacritic and other valid letters from European languages. What I don't want is numbers, spaces like “ ” or “ Tom”, or special characters like !”£$% etc.

So far I'm finding it very confusing.

I started with this

[A-Za-z.\\s\\-\\.\\W]+$

And ended up with this:

[A-Za-z.\\s\\-\\.\\D[^!\"£$%\\^&*:;@#~,/?]]+$

Using the cavat to say none of the inner square brackets, according to the documentation

Anyone have any suggestions for a new regex or reasons why the above isn't working?

Upvotes: 0

Views: 191

Answers (2)

Kishor Sharma
Kishor Sharma

Reputation: 599

Use: (?=.*[@#$%&\s]) - Return true when atleast one special character (from set) and also if username contain space.

you can add more special character as per your requirment. For Example:

String str = "k$shor";
String regex = "(?=.*[@#$%&\\s])";
Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(str);
System.out.println(matcher.find()); => gives true

Upvotes: 0

Cephalopod
Cephalopod

Reputation: 15145

For my answer, I want to use a simpler regex similar to yours: [A-Z[^!]]+, which means "At least once: (a character from A to Z) or (a character that is not '!').
Note that "not '!'" already includes A to Z. So everything in the outer character group([A-Z...) is pointless.

Try [\p{Alpha}'-.]+ and compile the regex with the Pattern.UNICODE_CHARACTER_CLASS flag.

Upvotes: 1

Related Questions