looking for non-applet science simulations

[Bill Stanard]

For my programming students, I'm looking for non-applet (and non-JApplet) science simulations written in java. Most simulations seem to be in applet or JApplet format. Any suggestions on where to look for simulations that would be interesting to programmers and science (physics, chemistry, biology, et cetera) students?

cheers!
Bill

<[e-mail]>

[Ernest Friedman-Hill]

Why non-Applet?

Most Applets and JApplets can be run as applications with the addition of a suitable main() routine:

import java.applet.*;
import java.awt.*;
 
class SimulationRunner {
  public static void main(String[] argv) {
    Applet a = new TheApplet();
    Frame f = new Frame();
    f.add(a);
    f.setSize(600, 400); // Whatever size the applet wants to be
    f.setVisible(true);
    a.init();
    a.start();
  }
}

As I said, this will work for many applets -- but not all.

[Bill Stanard]

Assuming a simple applet such as the following...

  
import java.awt.*;
import java.applet.*;
 
public class WelcomeApplet extends Applet
   {
      Label helloLabel = new Label("Welcome to Java!");    
       public void init()
      {
         setForeground(Color.red);
         add(helloLabel);
      }
   }

...where do I add the code that you suggest? Or do I rewrite my code to fit the pattern that you suggest? Sorry to be so thick...

[Ernest Friedman-Hill]

The important part of this is the main() method. I showed inside an entirely separate class, but you can just take the "public static void main() { ... }" part and put it into the WelcomeApplet class itself. Change "TheApplet" in my code to "WelcomeApplet", compile the applet, and then run the result with

java WelcomeApplet

from the command line.

[Layne Lund]

Of course, if you don't want to "pollute" your applet class, you can use Ernest's example as a separate class in a separate file basically as it is.

Layne

[Henry Wong]

Is the "appletviewer" option still available? That use to be my favorite option to run applets from the command line.

Henry

[Bill Stanard]

Thanks, Ernest & Layne,
It works... but... I need to grab and then resize the frame before it shows anything (in the case of the WelcomeApplet, the helloLabel). Any idea why this is? I've noticed it a lot with some of the applets I write, that text fields or labels are quite often hidden until the applet (frame) is grabbed and resized. Then all is well.
cheers!
Bill

[Ernest Friedman-Hill]

Because the components are added after the applet is visible on the screen; the LayoutManager needs a special notification that you're done changing the screen before it actually does anything. You should be able to fix this by moving the init() call to just before the setVisible() call -- I suppose I've misled you in not doing it that way in the first place.