Quantum Cookbook

General Introduction

Hierarchical State Machines (HSMs) are a superb formalism for specifying and implementing event-driven systems. Active objects in the UML specification are the roots of threads of control in multitasking systems and engage one another asynchronously via events. The UML further proposes the UML variant of statecharts, with which to model the behavior of event-driven active objects. Here you can find a brief introduction to these profound concepts.

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State Machine Recipes

State Machine recipes provide step-by-step instructions for coding state machines. You'll learn how to code hierarchical states, transitions, internal transitions, initial transitions, entry/exit actions, guards, choice-points, etc.

RECIPE: Designing a HSM

Designing a Hierarchical State Machine (HSM) is not a strict science. Typically it is an iterative and incremental process: you design a little, code a little, test a little, and so on. In that manner you may converge at a correct design in many different ways, and typically also, more than one correct HSM design exists. To focus the discussion, this recipe walks you through a design of a simple four-operation calculator. Obviously, the presented solution is just one of the many possible.

RECIPE: Coding a HSM in C

This recipe walks you through the details of implementing a nontrivial Hierarchical State Machine (HSM) in C.

RECIPE: Coding a HSM in C++

This recipe walks you through the details of implementing a nontrivial Hierarchical State Machine (HSM) in C++.

RECIPE: Coding a HSM in Java

This recipe walks you through the details of implementing a nontrivial Hierarchical State Machine (HSM) in Java.

RECIPE: Coding a HSM in Action Script

This recipe walks you through the details of implementing a nontrivial Hierarchical State Machine (HSM) in Action Script.

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Active Objects Recipes

Active Object recipes provide step-by-step instructions for coding active objects. You'll learn how to derive your own active objects, how to add state behavior, how to start an active object, how to pass events, etc.

Object Oriented Recipes

Object Oriented Programming (OOP) is a fundamental way of design, and not the use of a particular language or a design-automation tool. Here you can learn how to implement the most important OOP concepts in C