Is it possible to use split function with a '.' as a delimiting regular expression?

Question

I wanna split the content of a string variable, but I wanna use the point as a delimiting regular expression, my code doesn't work.

public class Test {

    public static void main(String [] a){
        String ch = "r.a.c.h.i.d";
        String[] tab;
        tab=ch.split(".");
        System.out.println(tab.length);
        for(String e : tab)System.out.println(e);
    }
}

score 1 · Answer 1 · answered Feb 04 '15 at 01:18

1

Change tab=ch.split("."); to tab=ch.split("\\.");. You need to escape the dot because otherwise it's treated as a special character in the regex passed to split.

answered Feb 04 '15 at 01:18

Mateusz Dymczyk

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It's a shame Java doesn't let us use `@` to denote string literals like C# does – Shadow Feb 04 '15 at 01:19
@user3189142 it is indeed a shame! Not the only thing I wish Java had that's already in C#. – Mateusz Dymczyk Feb 04 '15 at 01:20

score 1 · Answer 2 · answered Feb 04 '15 at 01:20

1

tab = ch.split("\\.");

One slash is the escape character for the regex. But in Java you need to have a second slash because you have to escape the first slash.

answered Feb 04 '15 at 01:20

Jose Martinez

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score 0 · Answer 3 · edited Jun 20 '20 at 09:12

Yes, it's possible. In a regular expression, . means any character.

Predefined character classes

. Any character (may or may not match line terminators)

So you must escape it to provide the literal . meaning. Escape it with a backslash character, providing two backslashes, because Java needs the backslash character itself escaped.

Use the regular expression "\\.".

In general, to get the literal characters out of an expression that may contain special-meaning characters, you can use the Pattern.quote method.

This method produces a String that can be used to create a Pattern that would match the string s as if it were a literal pattern.

split(Pattern.quote("."))

Is it possible to use split function with a '.' as a delimiting regular expression?

3 Answers3