Using Regex for Capitalization

[Lil_Aziz1]

public class Grammar {
	
	private static String capitalize(String str) {
		return str.toLowerCase().replaceAll("(^|\\s)([a-z])","$1$2".toUpperCase());
		
	}
	
	public static void main(String[] args) {
		System.out.println(capitalize("hi dude"));
	}
}

what's wrong with this? It won't capitalize the first letter of every word. Any help appreciated.

[Fubarable]

It calls toUpperCase on the String literal "$1$2", which does nothing, and then uses that result as the replacement String.

[Lil_Aziz1]

is it possible for me to evaluate $1$2 first?

p.s: I need to do this without using loops, recursive, or anything that is not regex.

[Fubarable]

is it possible for me to evaluate $1$2 first?

I'm not familiar with a way to do this (but this doesn't mean it doesn't exist).

p.s: I need to do this without using loops, recursive, or anything that is not regex.

Why?

[Lil_Aziz1]

:( I can't find anything on google either. I need to do it using regex because it's a challenge from a friend.