CODEWITHSUNDEEP
javaregex
user1371541
user1371541

Reputation: 43

Java Regex match digital, character, comma, and quote...

I'm new to regular expressions...

I have a problem about the regular expression that will match a string only contains:

0-9, a-z, A-Z, space, comma, and single quote?

If the string contain any char that doesn't belong the above expression, it is invalid.

Is that something like:

Pattern p = Pattern.compile("\\s[a-zA-Z0-9,']");
Matcher m = p.matcher("to be or not");
boolean b = m.lookingAt();

Thank you!

Upvotes: 0

Views: 3655

Answers (3)

eakst7
eakst7

Reputation: 690

Note that \s will match any whitespace character (including newlines, tabs, carriage returns, etc.) and not only the space character.

You probably want something like this:

"^[a-zA-Z0-9,' ]+$"

Upvotes: 1

Tim Pietzcker
Tim Pietzcker

Reputation: 336158

You need to include the space inside the character class and allow more than one character:

Pattern p = Pattern.compile("[\\sa-zA-Z0-9,']*");
Matcher m = p.matcher("to be or not");
boolean b = m.matches();

Upvotes: 2

AlexR
AlexR

Reputation: 115338

Fix your expression adding bounds:

Pattern p = Pattern.compile("^\\s[a-zA-Z0-9,']+$");

Now your can say m.find() and be sure that this returns true only if your string contains the enumerated symbols only. BTW is it mistake that you put \\s in the beginning? This means that the string must start from single white space. If this is not the requirement just remove this.

Upvotes: 2

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