Interview Question Remove all Spaces in String

package com.javacoding;

public class RemoveAllSpaceOfString {
public static String replaceAllSpace(String s1) {
  String s2=s1.replaceAll("\\s", "");
System.out.println(s2);
return s1;
}
public static void main(String[] args) {
replaceAllSpace("ahfajk    asf   fgdss");

}

}