Java demo: How it works
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import java . . . . .

This is the equivalent of #import in C or Uses in Pascal - tells
the compiler what extra information is needed to compile the
program.

public class banner extends java.applet.Applet{

1. The main class MUST have the same name as the file.
2. Unlike C/Pascal, file names ARE case sensitive
3. The main class MUST be declared "public" so that the browser
	can load it.
4. ALL Java code for a browser will "extend" (i.e. be derived
	from) the base class, java.applet.Applet

	String StrLine[]= new String[1];
	Font appFont;

Java has built in String functions and the first line creates
a new, empty, string in memory. appFont is a variable of type
Font. (Pascal note: the keyword var is not accepted.)

   public void paint(Graphics g){
	FontMetrics fm;
	fm=g.getFontMetrics(appFont);
	Rectangle r = bounds();
	g.setColor(Color.red);
	g.setFont(appFont);
   	g.drawString(StrLine[0], (r.width - 
fm.stringWidth(StrLine[0]))/2, (r.height - fm.getHeight())/2);
	stop();
   }
}

paint has similar functions to Paint under Windows. FontMetrics
too is similar, containing details of the measurements of the
current font. Rectangle is self-explanatory.
Note that bounds() is pre-defined within Java as returning the
bounds of the applet as a rectangle. drawString needs to be told
where to draw the text. Rectangle includes two members, width
and height. FontMetrics also contains two measurements,
stringWidth(String) and getHeight().  Note that r.width is a 
variable but fm.getHeight() is a function (similar to a Pascal
procedure).

stop(); just notifies the browser that the applet has completed
and the document can now be shown as "Done.".