Nt1330 Unit 4 Assignment

Homework #1 Assignment
1. What is the OO principle of the inheritance? What benefit is inheritance to systems designers?
Ans: if a language supports oop’s principles then that language called as object oriented programming language.
Inheritance: Acquiring the properties from superclass to subclass is nothing but inheritance.
• By using extends keyword we can perform inheritance between classes.
Class subclass extends superclass
{
}
Inheritance benefits:
• Inheritance hierarchy shows an “is-a” relationship and not a “has-a” relationship.
• Reuse code from the super classes.
• Same class and methods is applicable for different data types.
• The class hierarchy is reasonably shallow, and other developers are not likely to add many more levels.
•

Explain the principle of data encapsulation. Is encapsulation the same thing as information hiding? Why or why not?
Ans: Encapsulation is a mechanism to combined variables and methods in to a single unit.
• Class is the best example for encapsulation
• Encapsulation are two types
1) Tightly encapsulation
2) Loosely encapsulation
• Encapsulation is then the technique for packaging the information in such a way as to hide what should be hidden, and make visible what is intended to be visible. Remembering that encapsulation is achieved through information hiding.
4. List the Systems Development Lifecycle Phases. Discuss the major goals at each stage.
Ans: SDLC is a process followed for a software project, within a software organization. It consists of a detailed plan describing how to develop, maintain, replace and alter or enhance specific software. The life cycle defines a methodology for improving the quality of software and the overall development process.
There are following six phases in every Software development life cycle model:
1. Requirement gathering and analysis
2. Design
3. Implementation or coding
4. Testing
5. Deployment
6.