How to add whitepaces between each capital letter?

Question

I try to write a regular expression in order to:

Add white spaces between each capital letter.
Remove all numbers.

I have the text: ClassNameOne839, and I want to get the text: Class Name One

There is a library function which do it? or any regular expression?

i doubt that there is a library for that. try to write the regex and we might help you — Philipp Sander, Dec 19 '13 at 09:07
possible duplicate of http://stackoverflow.com/q/272633/2006839 — Lakshmi, Dec 19 '13 at 09:09
String s = MyDocumentFileIsHere; String textWithSpace = s.replaceAll("(.)([A-Z])", "$1 $2"); holder.titleTxt.setText(textWithSpace); — Fakhar, Aug 07 '14 at 12:39

Keppil · Accepted Answer · 2013-12-19T09:16:18.017

21

You can use a combination of replaceAll() calls like this:

String text = "ClassNameOne839";
String cleanText = text.replaceAll("\\d+", "").replaceAll("(.)([A-Z])", "$1 $2");

This first removes all numbers, and then adds a space before all upper-case letters that are not at the beginning of the String. $1 and $2 are references to the first and second groups of the regex.

edited Dec 19 '13 at 09:16

answered Dec 19 '13 at 09:10

Keppil

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In case you want to preserve numbers and Google brought you here, try this: String cleanText = text.replaceAll("(.)([A-Z0-9]\\w)", "$1 $2"); Output: "Class Name One 839" – Zeek Aran Nov 23 '18 at 15:51

score 1 · Answer 2 · answered Dec 19 '13 at 09:39

org.apache.commons.lang.StringUtils.splitByCharacterTypeCamelCase

Does almost everything you need ;) Try this one:

cleanText = StringUtils.join(StringUtils.splitByCharacterTypeCamelCase(in.replaceAll("\\d+", "")), " ");

Should be much faster than regexps.

Bart Enkelaar · Answer 3 · 2013-12-19T09:17:41.033

The following regular expression [A-Z][a-z]+(?=[A-Z\s\b0-9]) Would match each individual capitalized word followed by another capital letter, a space character or digit. Simply print each result in a row with a space behind it and you're set

Edit: This is ofcourse given that your capitalized names don't contain weird characters, the use would be something like this:

Matcher matcher = Pattern.compile("[A-Z][a-z]+(?=[A-Z\s\b0-9])").matcher(input);
while(matcher.find()) {
   string = string + matcher.group();
}
Sytem.out.println(string);

score 0 · Answer 4 · answered Dec 19 '13 at 09:16

String result = "ClassName399".replaceAll("\\d", "").replaceAll("([A-Z])", "$1 ");

The first expression will detect all integers in the string (\\d) and delete them, the second looks for any capital letter (using the range operator []) and then takes what you found $1 and adds a space after it.

Please refer to Java Pattern class for more info on regular expressions.

How to add whitepaces between each capital letter?

4 Answers4