Java Run Help

Question

I just started learning Java yesterday. I haven?t programmed since Basic. I wrote the first sample code from the training material and compiled it successfully. When I try and run the .class file I get what is shown in the screenshot below. I tried the code from my work computer and it ran just fine. Does anyone know what the error in the screenshot means?
Screenshot
Here is the code:
import java.awt.Frame;
import java.awt.Label;
public class HowdyWindow extends Frame {
    public static void main(String arg[]) {
        new HowdyWindow();
    HowdyWindow() {
        Label label;
        label = new Label("Howdy!");
        add(label);
        pack();
        show();
}Edited by: madlduke on Jun 4, 2010 7:49 PM
Edited by: madlduke on Jun 4, 2010 7:52 PM

Answer 1

It means what it says: it can't find the classes. The JVM uses a list of places to look for class files, called the "classpath". You have to tell it what that list is, otherwise it can't find the files.
Try this:
java -cp . HowdyWindowas long as you're in the directory where the class files are, it should work (at least it should find and try to run the class). -cp is an alias for -classpath; you can use either.
By the way, you should put the error message in your post rather than linking to a screenshot. Just cut-and-paste it into your post.