Software Reuse Landscape Overview

System Reuse

Reusing complete systems, including multiple application programs.

Application Reuse

Reusing an application by incorporating it into others or developing application families.

Component Reuse

Reusing components of an application, from sub-systems to single objects.

Object and Function Reuse

Reusing small-scale software components implementing a single object or function.

Accelerated Development

Speeding up system production by reducing development and validation time through software reuse.

Effective Use of Specialists

Developing reusable software by specialists to encapsulate their knowledge.

Increased Dependability

Reused software is more dependable due to prior testing and fixing of design and implementation faults.

Lower Development Costs

Reducing costs by writing fewer lines of code through software reuse.

Reduced Process Risk

Knowing existing software costs versus uncertain development costs reduces project cost estimation errors.

Standards Compliance

Implementing standards like user interface standards using reusable components for consistency.

Creating a Component Library

Populating and ensuring usability of a reusable component library, adapting development processes.

Adapting Reusable Components

Discovering, understanding, and sometimes modifying reusable components for new environments.

Increased Maintenance Costs

Higher maintenance costs if source code of reused software is unavailable, leading to compatibility issues.

Lack of Tool Support

Some tools do not support development with reuse, complicating integration with component libraries.

Not-Invented-Here Syndrome

Engineers rewriting components due to trust issues or the challenge of creating original software.

Range of Reuse Approaches

Various levels of reuse from simple functions to complete application systems.

Application Frameworks

Collections of abstract and concrete classes adapted to create application systems.

Application System Integration

Integrating multiple application systems for extended functionality.

Architectural Patterns

Using standard software architectures to support common application system types.

Aspect-Oriented Software Development

Weaving shared components into applications at different stages during compilation.

Component-Based Software Engineering

Developing systems by integrating collections of objects conforming to component-model standards.

Configurable Application Systems

Designing domain-specific systems configurable to specific customer needs.

Design Patterns

Representing generic abstractions across applications as design patterns.

ERP Systems

Configuring large-scale systems encapsulating generic business functionality for organizations.

Legacy System Wrapping

Providing access to legacy systems through defined interfaces.

Model-Driven Engineering

Representing software as domain models and generating code from these models.

Program Generators

Systems embedding knowledge to generate domain-specific systems from user-supplied models.

Program Libraries

Class and function libraries for commonly used abstractions available for reuse.

Service-Oriented Systems

Developing systems by linking shared services, which may be externally provided.

Software Product Lines

Generalizing application types around a common architecture for adaptation to different customers.

Systems of Systems

Integrating two or more distributed systems to create a new system.

Framework Definition

An integrated set of software artifacts collaborating to provide a reusable architecture for related applications.

Framework Complexity

Frameworks provide a skeleton architecture but can be complex, requiring time to use effectively.

System Infrastructure Frameworks

Supporting the development of system infrastructures like communications, user interfaces, and compilers.

Middleware Integration Frameworks

Standards and classes supporting component communication and information exchange.

Middleware integration frameworks

Support component communication and information exchange

Enterprise application frameworks

Aid in developing specific application types like telecommunications

Software product lines

Applications with generic functionality adaptable for specific contexts

Software product line

Set of applications with shared components but specialized for different needs

Adaptation in product lines

Involves component/system configuration, adding new components, selecting from a library, and modifying components

Core components

Provide infrastructure support, remain unmodified in new product line instances

Configurable components

Modified and specialized for new applications, may use a built-in configuration language

Domain-specific components

Specialized components replaced in new product line instances

Object-oriented features in frameworks

Application frameworks use polymorphism for extensions, unlike product lines

Architectures in product lines

Structured to separate subsystems and allow modifications

Elicit stakeholder requirements

Use existing family members as prototypes to understand needs

Design time configuration

Modifying a common product line core to create a new system

Deployment time configuration

Generic system designed for customer configuration using embedded data

Component selection

Choosing modules providing required functionality in a system

Workflow and rule definition

Defining information processing workflows and validation rules

Parameter definition

Specifying values for system parameters reflecting the application instance

Application system product

Adaptable software system without changing source code, with generic features

Configurable application systems

Generic systems designed to support specific business types or activities

Domain-specific systems

Support business functions likely needed by various users

Integrated application systems

Include multiple application system products or legacy systems

Service-oriented approach

Access application system functionality through standard service interfaces

Software reuse benefits

Lower costs, faster development, increased dependability

Application frameworks

Collections of objects designed for reuse through specialization

Application system reuse

Reusing large-scale off-the-shelf systems to reduce costs and development time

Potential problems with system reuse

Lack of control over functionality, system evolution, inter-operability, and vendor support

Design patterns in frameworks

Incorporate good design practices for reuse and specialization