Question

I am looking for a regex to split a string containing ().

This is what I have

String regex = "(?=\\()|()"

The first part is correct so that it starts with the “(“. I need the second part to end on the “)”, but if there is a number after the “)” it need to end on the number.

example
Fe2(CH3)2(CH2O)(CH3)

This needs to split into

Fe2

(CH3)2

(CH2O)

(CH3)

The number after the “)” can be either a single or double digit.

I also needs to split Fe(C5H5)2O4(CH3) for example into

Fe

(C5H5)2

O4

(CH3)

Answer 1

Updated, the new logic: match either some letter chars or something parenthesized, followed by optional digits.

final String f = "Fe2(CH3)2O4(CH2O)2(CH3)";
final Matcher m = Pattern.compile("(\\p{L}+|\\(.*?\\))\\d*").matcher(f);
while (m.find()) System.out.println(m.group());