CODEWITHSUNDEEP
javaregex
Zacharia Mwangi
Zacharia Mwangi

Reputation: 53

Make Regex Match Whitespaces in Java

How can I make this regex match white spaces? Currently, it can only match the following:

abcdatcsdotuniversitydotedu

I would like it to mach the following:

abcd at cs dot university dot edu

This is the Regex:

([A-Za-z][A-Za-z0-9.\\-_]*)\\s[ ]?(at)[ ]*([A-Za-z][A-Za-z0-9\\-_(dot)]*[ ]?(dot)[ ]*[A-Za-z]+)

Upvotes: 0

Views: 7538

Answers (2)

egemen
egemen

Reputation: 839

public static boolean isAlphaNumericWithWhiteSpace(String text) {
        return text != null && text.matches("^[\\p{L}\\p{N}ın\\s]*$");
    }

\p{L} matches a single code point in the category "letter".

\p{N} matches any kind of numeric character in any script.

I am using this code.

Upvotes: 1

MT0
MT0

Reputation: 167982

\s matches a white-space character and when this is used in a java string you need to escape the \ so it would be \\s. If you want to match zero-or-more white-space then use \\s*.

This will match a single domain and TLD:

([A-Za-z][A-Za-z0-9.\\-_]*)\\s*(at)\\s*([A-Za-z][A-Za-z0-9\\-_()]*\\s*(dot)\\s*[A-Za-z]+)

However, you are trying to match multiple levels of sub-domains so you need to wrap the domain part of the regular expression ([A-Za-z][A-Za-z0-9\\-_()]*\\s*(dot)\\s* in ()+ to get one-or-more of them:

([A-Za-z][A-Za-z0-9.\\-_]*)\\s*(at)\\s*(([A-Za-z][A-Za-z0-9\\-_()]*\\s*(dot)\\s*)+[A-Za-z]+)
                                       ^                                        ^^

Something like this:

public class RegexpMatch {
    static Pattern Regex = Pattern.compile(
            "([A-Za-z][A-Za-z0-9.\\-_]*)\\s*(at)\\s*(([A-Za-z][A-Za-z0-9\\-_()]*\\s*(dot)\\s*)+[A-Za-z]+)"
        );

    public static void main( final String[] args ){
        final String[] tests = {
                "abcdatcsdotuniversitydotedu",
                "abcd at cs dot university dot edu"
        };

        for ( final String test : tests )
            System.out.println( test + " - "  + ( Regex.matcher( test ).matches() ? "Match" : "No Match" ) );
    }
}

Which outputs:

abcdatcsdotuniversitydotedu - Match
abcd at cs dot university dot edu - Match

Upvotes: 3

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