String.Split - Unexpected behaviour

Question

I am trying to split a string as follows

String string = "mike|ricki"

If I do the following string.split("|") I would expect an array of 2 elements, "mike" and "ricki". Instead I am getting the following

[, m, i, k, e, |, r, i, c, k, i]

Am i doing something fundamentally wrong here?

Related [Using split() with “|” character](http://stackoverflow.com/questions/20409916/using-split-with-character) — Pshemo, Aug 01 '14 at 20:21

score 3 · Accepted Answer · answered Aug 01 '14 at 20:16

Yes. Pipe character | is a special character in regular expressions. You must escape it by using \. The escape string would be \|, but in Java the backslash \ is a special character for escape in literal Strings, so you have to double escape it and use \\|:

String[] names = string.split("\\|");
System.out.println(Arrays.toString(names));

Roberto Linares · Answer 2 · 2014-08-01T20:53:31.417

2

If you read the String.split() Java Documentation, it says that it can receive a Regular Expression as an input.

The Pipe character | is a special character in regular expressions so if you want to use it as a literal you have to escape it like \\|

So your code have to be:

String[] splitted = string.split("\\|");

EDIT : Corrected sample code.

edited Aug 01 '14 at 20:53

answered Aug 01 '14 at 20:16

Roberto Linares

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-1: Your answer was right until you added that very odd line of code at the end of your answer =\. You need to escape the regular expression, not the String where you will apply the regex. – Luiggi Mendoza Aug 01 '14 at 20:18
You don't need the original string to change, just the regex you're matching in the split – Paolo Aug 01 '14 at 20:18
Ups! I will corect it. – Roberto Linares Aug 01 '14 at 20:52

score 0 · Answer 3 · answered Aug 01 '14 at 20:17

0

String.split takes a regular expression. The pipe character has a special meaning in regex so it's not matching as you were expecting.

Try String.split("\\|") instead.

The backslash tells regex to treat the pipe as a literal character.

answered Aug 01 '14 at 20:17

Paolo

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String.Split - Unexpected behaviour

3 Answers3