String From User Not Removing Spaces

I'm not sure why but my infix string isn't removing the spaces. Here is the part of the code:

Scanner s = new Scanner(System.in);
System.out.println("Enter Infix express: ");
String infix = s.nextLine();
infix.replaceAll("\s", "").trim();
System.out.println(infix);
InfixtoPostfix convert = new InfixtoPostfix(infix);
String postfix = convert.toPostFix();
System.out.println("Converted Express: " + postfix);

Is there something I'm doing wrong? Here is the output when I run it:

Enter Infix expression:
(7 + x) * (8 – 2) / 4 + (x + 2)
(7 + x) * (8 – 2) / 4 + (x + 2)
Converted Expression: 7 x+ 8 – 2* /4 x 2++