Splitting a Java String by the pipe symbol using split("|")

Question

The Java official documentation states:

The string "boo:and:foo", for example, yields the following results with these expressions Regex Result :

{ "boo", "and", "foo" }"

And that's the way I need it to work. However, if I run this:

public static void main(String[] args){
        String test = "A|B|C||D";

        String[] result = test.split("|");

        for(String s : result){
            System.out.println(">"+s+"<");
        }
    }

it prints:

><
>A<
>|<
>B<
>|<
>C<
>|<
>|<
>D<

Which is far from what I would expect:

>A<
>B<
>C<
><
>D<

Why is this happening?

Possible duplicate of [How to split a string in Java](http://stackoverflow.com/questions/3481828/how-to-split-a-string-in-java) — KIBOU Hassan, May 02 '17 at 13:13

score 454 · Accepted Answer · edited Nov 28 '16 at 10:54

454

You need

test.split("\\|");

split uses regular expression and in regex | is a metacharacter representing the OR operator. You need to escape that character using \ (written in String as "\\" since \ is also a metacharacter in String literals and require another \ to escape it).

You can also use

test.split(Pattern.quote("|"));

and let Pattern.quote create the escaped version of the regex representing |.

edited Nov 28 '16 at 10:54

Wilfred Hughes

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answered May 29 '12 at 09:10

jmj

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It is, [`split()`](http://docs.oracle.com/javase/6/docs/api/java/lang/String.html#split%28java.lang.String%29) method takes regex and `|` is special character for reg ex – jmj May 29 '12 at 09:16
1

you are my second choice as a moderator on stack overflow. All the best. – Däñish Shärmà Nov 19 '16 at 11:11

score 42 · Answer 2 · edited Oct 01 '19 at 20:12

42

Use proper escaping: string.split("\\|")

Or, in Java 5+, use the helper Pattern.quote() which has been created for exactly this purpose:

string.split(Pattern.quote("|"))

which works with arbitrary input strings. Very useful when you need to quote / escape user input.

edited Oct 01 '19 at 20:12

Basil Bourque

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answered Jan 09 '14 at 16:07

Aaron Digulla

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Not shure when the transition was made, but in Java 8, one would use `Pattern.quote()`. – randers Jan 24 '16 at 16:42

score 6 · Answer 3 · edited Sep 01 '16 at 09:16

6

Use this code:

public static void main(String[] args) {
    String test = "A|B|C||D";

    String[] result = test.split("\\|");

    for (String s : result) {
        System.out.println(">" + s + "<");
    }
}

edited Sep 01 '16 at 09:16

DimaSan

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answered Sep 01 '16 at 08:46

berliandi

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This solution is already pointed by accepted answer. No need to repeat it. – Pshemo Jan 14 '17 at 16:29

score 3 · Answer 4 · answered Nov 29 '15 at 13:48

3

You could also use the apache library and do this:

StringUtils.split(test, "|");

answered Nov 29 '15 at 13:48

Simon

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score 2 · Answer 5 · edited Nov 05 '16 at 02:08

2

You can also use .split("[|]").

(I used this instead of .split("\\|"), which didn't work for me.)

edited Nov 05 '16 at 02:08

Laurel

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answered Nov 04 '16 at 12:40

Homer

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Both versions should work fine. If one doesn't it suggest problem is somewhere else. – Pshemo Jan 14 '17 at 16:30
@Pshemo This does however add an interesting flavor, that some reserved symbols does not have to be escaped if put inside brackets. – Pax Vobiscum Sep 11 '17 at 09:12

score 1 · Answer 6 · answered Sep 20 '18 at 11:14

1

test.split("\\|",999);

Specifing a limit or max will be accurate for examples like: "boo|||a" or "||boo|" or " |||"

But test.split("\\|"); will return different length strings arrays for the same examples.

use reference: link

answered Sep 20 '18 at 11:14

Ryan Augustine

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score -2 · Answer 7 · answered Aug 20 '13 at 11:02

-2

the split() method takes a regular expression as an argument

answered Aug 20 '13 at 11:02

Stormy

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Splitting a Java String by the pipe symbol using split("|")

7 Answers7

Linked

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