Software Design

The Jam-O-Drum’s software library was designed with flexibility and extensibility in mind.  We chose Java as the language of implementation because of its suitability for rapid prototyping as well as its high degree of object orientedness.  We knew from the beginning that we wanted the creation of new experiences to be easy and standardized, so we made a set of interfaces through which all experiences communicate with the system.  We also created a Control Panel that is a centralized way to start and stop the Jam-O-Drum experiences.

There are two main interfaces that experience authors must know about: Controllable and Input.  Every experience created for the Jam-O-Drum needs to implement the Controllable interface. This allows the Control Panel to start and stop the experience.  Controllable is a pure Java interface, so no requirements are made on how the experience interacts with the rest of the system.  There have been experiences implemented in pure Java, and others that use the Java Native Interface to communicate with low-level libraries written in C++ (such as DirectSound).

When starting the experience, the Control Panel passes the Controllable object an instance of the Input object.  This object is the way that input from the various parts of the Jam-O-Drum (the turntables and drumpads) gets sent to the experience.  Interaction with this object is simple – experiences implement the padListener for drumpad input, and diskListener for turntable input, and an instance of each of those listeners is passed to the Input object.  When player interactions are received by the system, the Input object calls the appropriate functions on the Listener objects.