1. An interrupt-driven system for controlling a spray system including a plurality of spray nozzles, a fluid supply, and a spray controller having a processing unit and memory, said system comprising: an application file residing in the memory, the application file being a binary version of a functional block representation created using an object-oriented software program, the block diagram including a plurality of software objects representing the physical and logical properties of the spray system, the plurality of objects being interconnected to create the functional block representation; and a runtime engine residing in the memory for processing the application file, said runtime engine enabling communication between the plurality of objects and for processing interrupt signals provided by at least one of the plurality of objects, the interrupt signals being responsive to a stimulus detected by the spray controller.