Department of Information Technology
Sub Code: IT 1401 Sub Name: Component Based Technology
Unit : I (Introduction) Year / Sem: IV – VII
Part - A
1. What is the necessity of CBT?
Component Based Technology is a technology, which deals with the study and
developing of various software components for integrated applications.
2. What is a Component? [Univ Nov – 2007 / Reg - 2004]
Component is an Object written to some specification. The Components are mainly
developed for the reusable purpose and can be used in different environments.
3. What are the Characteristics of a Component?
It is a unit of independent deployment.
It is a unit of third-party composition.
It has no (externally) observable state.
4. Define Software Components. [Univ Nov - 2007]
According to the Definition of ECOOP “A Software component is a unit of
composition with contractually specified interfaces and explicit context dependencies only. A
software component can be deployed independently and is subject to composition by third
parties.”
5. Define the five Criteria for S/W components.
Multiple uses.
Non-Context Specific (don’t specific in changing situations).
Compatible with other components.
A unit of independent Deployment and Versioning.
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6. What are the Goals of Software Components?
Software Components are reusable of codes for integrated applications to increase the
programmer’s development or productivity.
Goals:
Reusability, program complexity decreased.
7. State some characteristics of an Object.
It is a unit of instantiation.
It has a unique identity.
It may have state and this can be externally observable.
It encapsulates its state and behaviour.
8. Define Class.
A Plan which exists before the object can come into existence.
Construction plan that describes the state space, initial state and behaviour of a new
object.
9. Define Prototype Object.
The Plan if it available implicitly in the form of an object already exists. In Prototype
object newly instantiated object needs to be set to an initial state and that initial state needs to
be a valid state. Ex: Robot.
10. Define Constructor
The code required controlling the object creation and initialization.
It is a part of the object’s class.
It can be an object of its own called as factory object.
11. What are the Characteristics of the Constructor?
Constructor uses the same name as class name.
While creating objects, the constructors are automatically executed.
Constructor should be declared only in public section.
Constructors don’t have any return type.
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12. Define Modules.
A module is a self-contained component of a system, which has all well-defined
interfaces to the other component.
13. Write some features of the Module?
Modules can easily be connected to or disconnected from the system.
Even modules that don’t contain any classes can function as components.
It doesn’t have the concept of instantiation.
It can contain multiple classes.(JAVA)
14. Define Modulo Programming.
Programming which is used in Modular Language is known as Modulo
Programming.
The entire problem is divided into group of modules.
Each module has its own name and it is used to perform a single task.
15. Name the terms used for Modules in languages.
In Ada Modular language modules are called as Packages.
In Eiffel language modules are called as Class.
In JAVA nested classes can create modules.
16. Define Interfaces.
An interface defines the communication boundary between two entities.
Interface are individual component of grammar which don’t function in isolation
Interface is a set of named operation that can be invoked by clients.
17. Give examples for different types of interfaces.
Interface between a human and computer is called a user interface.
Interface between hardware components are physical interface
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18. Define Access Point.
Access point is a point, which allows clients of a component to access the service,
provide by the components. Components will have multiple interfaces corresponding to the
different Access point. Eg: Data Bus
19. State the Types of interfaces.
Interfaces can be divided into two Direct (Procedure) and Indirect (object).
If a component may directly provide an interface then it is said to be
Procedural interface.
If a component may indirectly provide an interface then it is said to be Object
interface.
20. Define Callbacks.
A Call back is an executable code that is passed as an argument to other code. It is an
procedure that is passed to a library at one point, when the callback is said to be registered with
library.
Call back may also be regarded as a form of runtime binding.(Dynamic binding).
21. Define the features in Callbacks.
One Procedure is written to traverse the list.
Procedure uses application code to operate on each time.
Client never observes any intermediate state that library might go through.
Client has full control over its own state when calling a library procedure.
Introduction 4/8
22. Define Directory Services [Univ Nov - 2007]
Directory Services is a software application that store and organize information about
computer user’s and resources.
It supports callbacks to notify clients of changes in the managed directory.
Useful to keep a visual representation of the directory up to date.
23. What is Architecture?
Architecture is based on the principal consideration of overall functionality,
performance, reliability and security. It is a holistic view of a system.
Eg: Operating System.
24. What is Component Architecture?
Component Architecture is an architecture, which consists of a set of platform
decisions, set of component framework and an interoperation design for the component
framework.
25. Define Middleware.
Middleware is a name for the set of software that sits between various operating
systems and distributed programming platform. Modern Middleware blends both Message
Oriented and Object Oriented.
Introduction 5/8
26. Categorize the Middleware.
• Message oriented middleware (MOM)
• Object oriented middleware (OOM)
27. What is generative programming?
Generative programming aims at transformations approach to the construction of
Software.
28. Specify the areas used in generative approaches.
• Used to produce individual components.
• Used to enhance composed systems.
29. Specify the criteria that are used to fulfill the software definition.
• Multiple uses
• Non-context specific
• Composable with other component.
• Encapsulated.
30. Specify the fundamental properties of component technology.
• If a component fails to function it must not violate system-wide rules.
• Software development processes that do not depending on testing.
• Performance of a component system is affected in non-trivial ways by the
actual composition.
31. What is enhance composed systems and give example.
They need to be positioned in such a way that they do not interfere with the unit of
deployment characteristic of components.
Eg: JIT technique.
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BIG QUESTIONS
1. Explain the fundamental properties of component technology.
• Technological feasibility
• Technical problems
• Integration and testing
• Potential of software components
2. Explain briefly about component architecture.
• Role of architecture
• A tiered component architecture
• Components and middleware
3. Explain briefly about callbacks with example.
• Definition
• Diagram
• Explanation
• Eg: directory service
4. Write short notes on modules, interfaces.
• Modules
• interfaces
5. Write short notes on objects and software components.
• Software components
• Objects
Introduction 7/8
POSSIBLE 16 MARK QUESTIONS
1. What is Components? Explain the Characteristics of the components with objects.
Page No: 36-38.
2. Explain Software Components with example Page No: 41- 42.
3. Explain Interfaces and its types with an example. [Univ Nov - 2007] Page No: 49-53
4. Explain Callbacks with an example. [Univ Nov - 2007] Page No: 58-60.
5. Explain in detail about Directory Services with Component Pascal notation.
Page No: 60-62
6. Explain Modules and its usage in the real world. [Univ Nov - 2007] Page No: 39-40.
7. Explain the Problems faced before and after callbacks. Page No: 58-59.
8. Explain the Component Architecture with an example. Page No: 417-418.
9. What is Middleware and explain the Component and Middleware uses.
[Univ Nov - 2007] Page No: 423-424
10. Explain tiered component architecture. Page No: 421-422
TEXT BOOK:
COMPONENT SOTWARE beyond Object-Oriented Programming
AUTHOR NAME:
CLEMENS SZYPERSKI with Dominik Gruntz and Stephen Murer
Introduction 8/8