The purpose of the Technology Viewpoint is to classify the elements of the problem and the solution around well-known software paradigms and technologies.

Views

The following traceable architectural views explain the applied programming paradigms and technologies:

SAS_QP_OO

Object-oriented view

Description

This architecture specification of the QP Framework assumes an object-oriented view, utilizing the concepts such as:

class
inheritance
polymorphism
object-oriented design patterns
UML notation and semantics

Concerns

programming paradigm
software organization
software interfaces
information hiding

Anti-Concerns: The object-oriented view does not impose the choice of object-oriented programming language. In traditionally procedural languages, such as C, object-oriented concepts can be applied as design patterns. A set of such patterns for the C programming language is described in the reference Object-Oriented Programming in C [OO-in-C:23].

SAS_QP_EDA

Event-driven architecture view

Description: The QP Framework is a reusable event-driven architecture (EDA), where all interactions are triggered by events, which are delivered asynchronously and are processed without blocking.

Concerns

programming paradigm
software organization
real-time processing

Anti-Concerns: The EDA architecture underlying QP Framework is in contrast to the sequential architectures, such as a traditional Real-Time Operating System (RTOS), where the application explicitly awaits events in-line in the hard-coded blocking calls (e.g., time-delay, semaphore, etc.)

SAS_QP_AF

Application framework view

Description: QP Framework is an application framework defined as a reusable architecture for a specific problem domain (embedded, real-time systems in case of QP Framework).

Concerns

Application framework has the following key characteristics:

inversion of control: In a framework, unlike in a toolkit or in a standard end-application, the overall program's flow of control is not dictated by the application, but by the framework (the framework calls the application, not the other way around).
extensibility: application developers can extend the framework by deriving and specializing base classes provided inside the framework.
non-modifiable framework code: the framework code is not supposed to be modified, while accepting application-implemented extensions. In other words, developers can extend the framework, but cannot modify the framework.

Anti-concerns: Software organized as a framework significantly differs from software organized as a "toolkit", such as a traditional Real-Time Operating System (RTOS).

About this DocumentContext Viewpoint