My simulation is coded in Java 1.1.7B. It has been tested using Java SDK 1.1.7_v1a for Linux and Java SDK 1.2 (final) and SDK 1.1.7B on Win32. On these version of Java the appliaction runs fine, but in older version it does not. This means that in order for the following applet to run, you need a new JRE, which your browser should download automatically. In case you do not succeed in running the applet the source for the application is here, while the compiled application can be found here.
Before using the applet, please note the following:
In my implementation each token is run inside a seperate thread, which means that it continuosly checks its two neighbours. This reflects the "real-world" dynamics of the system.
This application/applet is not without its faults. It was a design decision, based on how Java assumes only a single button on a mouse (for compatability), not to make the user able to move tokens once they have been placed on the grid. This could have been fixed by for example allowing the user to move a token if a key is pressed when the mouse button is pushed. But I decided to leave that for the next version. Instead I opted for a simpler solution which gives the same functionality, allow the user to replace tokens by simply dropping a new token on top of it.