Split by capital letters in Java

Question

I need to split a string by capitals and preferably make subsequent words lower case;

for example

ThisIsAString becomes This is a string

Thanks

have you copied question from http://stackoverflow.com/questions/3752636/java-split-string-when-an-uppercase-letter-is-found — Jama A., Feb 10 '12 at 16:49
possible duplicate of [How do I convert CamelCase into human-readable names in Java?](http://stackoverflow.com/questions/2559759/how-do-i-convert-camelcase-into-human-readable-names-in-java) — Andrew, Feb 10 '12 at 17:04
Does this answer your question? [How do I convert CamelCase into human-readable names in Java?](https://stackoverflow.com/questions/2559759/how-do-i-convert-camelcase-into-human-readable-names-in-java) — Pino, May 20 '21 at 08:02

score 4 · Answer 1 · edited Nov 22 '19 at 02:26

4

If you want a string you can do so:

String str = "ThisIsAString";
String res = "";
for(int i = 0; i < str.length(); i++) {
   Character ch = str.charAt(i);
     if(Character.isUpperCase(ch))
       res += " " + Character.toLowerCase(ch);
     else
       res += ch;
}

edited Nov 22 '19 at 02:26

Marvin

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answered Feb 10 '12 at 17:04

Figus

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score 3 · Accepted Answer · edited May 23 '17 at 12:13

3

It looks like you want to convert camelcase into readable language. Is that the case?

If so, this solution should work for you - How do I convert CamelCase into human-readable names in Java?

If you want subsequent words lowercased, you'll have to split to handle that yourself.

edited May 23 '17 at 12:13

Community

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answered Feb 10 '12 at 16:55

I82Much

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score 1 · Answer 3 · answered Feb 10 '12 at 17:05

public static String cpt(String cpt){
    String new_string = "";
    for (int i=0; i < cpt.length(); i++){
        char c = cpt.charAt(i);
        if(Character.isUpperCase(c)){               
            new_string = new_string + " " + Character.toLowerCase(c);
        }
        else {
            new_string = new_string + c;
        }
    }
    return new_string;
}

score 0 · Answer 4 · answered Jul 28 '19 at 06:34

Total Number of Words in a Camel Case word using char casing identification

Solution: to Hacker Rank camel case problem: https://www.hackerrank.com/challenges/camelcase/problem

public static void camelCaseWordWithIndexs(String s) {


    int startIndex = 0;
    int endIndex = 0;

    for (int i = 0; i < s.length(); i++) {
        if (Character.isUpperCase(s.charAt(i)) || i == s.length() - 1) {
            startIndex = endIndex;
            endIndex = i != s.length() - 1 ? i : i + 1;
            System.out.println(s.substring(startIndex, endIndex));
        }
    }


}

Split by capital letters in Java

4 Answers4