You cannot run any of the Turtle subclasses outside of Jurtle.
Jurtle sets up the appropriate display area that Turtles require.

In theory I could extract the necessary classes for Turtles and
package them in a standalone jar. Then running a Turtle would open a
JFrame with just the Display area. However, this change is not high
on my priority list. If others request it, I will consider doing it
in a future release.


On Jul 13, 2005, at 12:19 PM, chander2010 wrote:

> Is there a way to run the BouncingBalls example from the command
> line? When I try to run the example and include the Jurtle.jar file
> in the classpath I get a NullPointerException. I would like to
> reapply this concept to launch my own graphic program. Is there some
> kind of Graphics or Component layouts that I need to setup before
> instantiating the BouncingBalls object?
>
> Exception in thread "main" java.lang.NullPointerException
> at com.otherwise.jurtle.Turtle.<init>(SourceFile:77)
> at BouncingBalls.<init>(BouncingBalls.java:22)
> at BouncingBalls.main(BouncingBalls.java:70)

--
Bill Tschumy
Otherwise -- Austin, TX
http://www.otherwise.com