Replace multiple spaces

Given a sentence with multiple spaces between words and also spaces in front and back of sentence how do you remove these extra spaces
-- during interview, try to give solution that use linux command or regex. It may be not what interviewer want, but show that u know something. and can solve things in different ways.
https://github.com/mission-peace/interview/blob/master/src/com/interview/regex/MultiSpaceReplacement.java
    public void replace(String str){
        Pattern pattern = Pattern.compile("^ +|  +| +$");
        Matcher matcher = pattern.matcher(str);
        System.out.println(matcher.replaceAll(""));
       
    }
   
    public static void main(String args[]){
        String str = "     This is Tushar  Roy  ";
        MultiSpaceReplacement mrs = new MultiSpaceReplacement();
        mrs.replace(str);
    }