Clock Applet

The applet uses the Java library classes Thread, Font, Calendar, Date and Graphics. 

The Program

importClass: Applet  java.applet.Applet
importClass: Thread  java.lang.Thread
importClass: Graphics  java.awt.Graphics
importClass: Font  java.awt.Font
importClass: Calendar  java.util.Calendar
importClass: Date  java.util.Date   

importInterface: Runnable  java.lang.Runnable

importMethod: setTime Calendar  setTime ( date -- )
importMethod: calendarGet  Calendar get ( int -- int )
importMethod: setFont  Graphics setFont ( font -- )
importMethod: drawString  Graphics drawString ( string int int -- )
importMethod: repaint  Applet repaint ( -- )
importMethod: startThread  Thread start ( -- )
importMethod: stopThread  Thread stop ( -- )   
importMethod: sleep Thread sleep ( long -- )

static importField: hourOfDay  Calendar HOUR_OF_DAY int
stativ importField: second   Calendar SECOND int
static importField: minute  Calendar MINUTE int
static importField: italic  Font ITALIC int
static importField: bold  Font BOLD int
 

public class: Clock  extends Applet  implements Runnable
 
static Calendar clockCalendar
Thread clockThread 
static Font clockFont 

i: clock.<init>   ( -- )
     InitSuper () ; 

i: clock.init   ( -- )
     CalendarInstance =: clockCalendar
     " TimesRoman" italic bold + 100 
     new clockFont ( string int int -- ) ; 

\ The browser creates an object of class clock and calls start(). The
\ object (this) is also an object of Runnable. 
i: clock.start   ( -- )
     this new Thread ( runnable -- ) =: clockThread
     clockThread startThread  ; 

\ Delivers the int value of the current hour. 
: hours   ( -- int )
     HourOfDay clockCalendar calendarGet  ; 

: minutes   ( -- int )
     Minute clockCalendar CalendarGet  ; 

: seconds   ( -- int )
     Second clockCalendar CalendarGet  ; 

: clockTimeString   ( -- string )
     new Date ()  clockCalendar setTime
     <#   seconds  # #  drop ascii : hold
          minutes  # #  drop ascii : hold      
          hours    # #  #>  ; 

\ Applet.repaint calls update, which clears the graphics and calls paint.
\ Overlays applet.paint. 
i: clock.paint   ( Graphics graf -- )
     clockFont graf setFont
     clockTimeString 40 100 graf DrawString  ; 

i: clock.run    ( -- )
     begin  this repaint
            1000. sleep
     again  ; 

i: clock.stop   ( -- )
     ClockThread stopThread  ; 





1998-2013 Wolf Wejgaard