Control as a State Machine Engine

First let us define the state machine: "the state machine is a machine which is an object but not an application object. It is a part of language substrate to support syntax of application object". The normal approach to implement control is to have a few ways of explicitly representing and executing state machines. For illustration, a general "state machine engine" class can provide capability to execute a state machine represented by table of transitions and actions provided by application. As you know, each object consists of its own independent state variable and can call on the state engine to determine next state and action.

This approach helps quickly progress from analysis model to a skeleton prototype of system by defining classes from object model, state machines from dynamic model and creating "stubs" of action routines. A stub can be termed as "the minimal definition of a subroutine or function without any internal code". So, if every stub-print out own name, this technique permits you to execute skeleton application to verify which the basic flow of control is correct or not.

State machine mechanisms can be created easily using the object oriented language.