I'm sure this is a silly question, but I'd like to iterate through the
system properties, and can't figure out from the Sun tutorial how to do
this.  Modifying the simplest HelloWorldApp:

---start---
import java.util.*;

class HelloWorldApp {
   public static void main(String[] args) {
       System.out.println("Hello World!"); //Display the string.

       Properties myprops = System.getProperties();
       // need to loop around these somehow and print out...
       for (Iterator i = myprops.iterator(); myprops.hasNext(); ) {
       }
   }
}
---end---

This won't compile:

HelloWorldApp.java:13: cannot find symbol
symbol  : method iterator()
location: class java.util.Properties
               for (Iterator i = myprops.iterator();
myprops.hasNext(); ) {
                                        ^
HelloWorldApp.java:13: cannot find symbol
symbol  : method hasNext()
location: class java.util.Properties
               for (Iterator i = myprops.iterator();
myprops.hasNext(); ) {
                                                            ^
2 errors

No doubt I am doing something really crass -- anyone care to help me?

Thanks,

Roger Pearse