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Charles Cusack
Computer Science
Hope College
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CountDown


Description

Run it
Download jar file (Right click)

CountDown.java
CountDownApplet.java

Description
CountDown is a simple demonstration of how to animate a drawing when a recursive method is involved. It is more complicated than other sorts of animation because if the recursive method just runs, only the final step of the animation will show. Thus, we need a way to slow it down.

One might think using the following would work:

      try { Thread.sleep(500); }
      catch (InterruptedException e){ }
However, this will not work if there are Swing/AWT components involved. For instance, if you click a button to make the animation start, the entire recursive method must finish executing before the button "unclicks" and the GUI updates. Thus, you get no animation.

The solution is to create a new Thread which executes the recursive method.

The JAR file is executable and contains BlueJ project files.