Visualising Components

Question!

Hav yuh luk inside komputer?

Check for the damaged component

Components! ForTheWin

Components?

“A software component is a software element that conforms to a component model and can be independently deployed and composed without modification according to composition standard.” - Council and Heinmann

Components are:

1. Implemented as program units
2. Self-contained System
3. Independently Deployable and Composable
4. Loosely Coupled

Design Principles

• Independent
• Hidden Implementation Complexity
• Well Defined Interfaces

Standards

Needs to be Defined for

• Inter-operability

Examples:

• Java Beans
• COM and .NET
• CORBA's CCM

But Too Much Standards has hindered to uptake of CBSE

Two Perspectives

Two Perspectives

1. Implementation
2. Architectural Abstraction

Component Model

Defines standards for component implementation, documentation and deployment

Component Model: Elements

• Interfaces
• Usage Information
• Deployment and Use

Interfaces

• Interface Definition
• Composition
• Specific Interface

Usage Information

• Naming Convention
• Meta-Data Function
• Customization

Deployment

• Packaging

Technologies and Framework

• Enforce a Component Model
• Support Limited Range of Component Types and Interaction among them

Pros and Cons

Pros!

• Remove Complexity
• Rapid Assembly
• Well Defined Software Architecture

Cons!

• Costly Development and Maintenance
• Difficulty in QA