Object Oriented Programming (Java)
Object Oriented Programming (July Oct 2018)
Introduction
Object-oriented programming (OOP) is a programming paradigm that represents the concept of “objects” that have data fields (attributes that describe the object) and associated procedures known as methods.
This section briefly describe basic idea on class and Objects
Download: 01 Class and Objects
More Methods on a class
Constructors
Constructor is a special type of subroutine called to create an object
Encapsulation
Encapsulation is a language mechanism for restricting access to some of the object’s components
Composition
Composition is a way to combine simple objects or data types into more complex ones
Download:02 Advance Methods on class
Sample Code: (This example demonstrates composition, constructors, methods… )
Inheritance
Object-oriented programming allows classes to inherit commonly used state and behavior from other classes
Download:03 Inheritance
Employee Example
Video Tutorials
More Advance Object Oriented Programming concepts
Overriding, Abstraction, Packages, Polymopism
Download: 04 Advance Methods in OOP
Code Examples (Java classes)
Download: OOP Menu-driven Application development example
Exception Handling
Download : Exception Handling Note
File Handling
Download Lecturer Note (Files) [Download]
Packages
Lab Activity 1:
Bank Account Example
Create a menu driven Java application to handle Bank Account information. Class diagram of the system is given below.
Tasks
- Complete each class
- Add menu for the application with following menu options
- Add new Account
- Deposit or withdraw amount
- Get balance for the given account
- Print all account information
- Exit
- Test your application
Note that: each methods has it normal meaning
Lab Activity 2
Transport Example
“Jaffna Travels” is a pioneer transport service company in Sri Lanka. It provides transport services between Colombo and Jaffna. The management of the company requires to develop an online ticket booking system to reserve the seats in a given bus. Assume that, a bus consists of 50 seats. One passenger can book any number of seats. However, it depends on the seats availability at that time. The passengers are allowed to board into the bus only from Colombo, Jaffna, Anuradhapura and Vavuniya. The passengers who are boarded to the bus from Anuradhapura or Vavuniya have to pay 25% additional charge. However, there are no additional chargers for children (half ticket). The Table 1 shows the price of a ticket for a journey.
Table 1. Price of a ticket
Write a menu driven Java Application to complete the system
The class diagram for the proposed system is given in the below.