Trim leading or trailing characters from a string? Trim leading or trailing characters from a string? java java

Trim leading or trailing characters from a string?


You could use

Leading:

System.out.println("//test/me".replaceAll("^/+", ""));

Trailing:

System.out.println("//test/me//".replaceAll("/+$", ""));


You can use Apache StringUtils.stripStart to trim leading characters, or StringUtils.stripEnd to trim trailing characters.

For example:

System.out.println(StringUtils.stripStart("//test/me", "/"));

will output:

test/me

Note that if for some reason you can't use the whole StringUtils library, you could just rip out the relevant parts, as detailed here:


Trim with Character, String, or Regex

If run-time is not a big issue for you, then this code will prove really helpful.

public class StringTrimmer {    public static String trim(String string, char ch){        return trim(string, ch, ch);    }    public static String trim(String string, char leadingChar, char trailingChar){        return string.replaceAll("^["+leadingChar+"]+|["+trailingChar+"]+$", "");    }    public static String trim(String string, String regex){        return trim(string, regex, regex);    }    public static String trim(String string, String leadingRegex, String trailingRegex){        return string.replaceAll("^("+leadingRegex+")+|("+trailingRegex+")+$", "");    }    // test    public static void main(String[] args) {        System.out.println(trim("110100", '1', '0')); // outputs: 01        System.out.println(trim("**Aa0*#**", '*')); // outputs: Aa0*#        System.out.println(trim("123##22222", "12", "22")); // outputs: 3##2        System.out.println(trim("101101##10101", "101")); // outputs: ##10        System.out.println(trim("123##abcde", "\\d", "[c-e]")); // outputs: ##ab    }}