In the following:

public class toupper {

   private static void upper(){

    String a = "chad";
    System.out.println("Upper Case is:" + a.toUpperCase());

   }

   public static void main (String[] args) {
    upper();
   }
}

Why isn't the line
String a = new String();

Necessary? I thought this line might be omitted because for whatever
reasons I was thinking toUpperCase() was a static method. It isn't.
Because when I change the line:

System.out.println("Upper Case is:" + a.toUpperCase());

to

System.out.println("Upper Case is:" + String.toUpperCase());

I get the following:

$javac toupper.java
toupper.java:6: non-static method toUpperCase() cannot be referenced
from a static context
       System.out.println("Upper Case is:" + String.toUpperCase());
                                                   ^
1 error