Object Oriented Programming
TeguhSutanto Si | STIKOM Surabaya
[email protected]|+628563076813|http://teguhsutanto.blogspot.com|http://blog.stikom.edu/teguh
GOAL 1.Students can understand the Object Oriented Programming concepts 2.Students can make a program in accordance with the rules of Object Oriented Programming
Object-oriented programming (OOP) is a programming paradigm using "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs
Object-oriented programming (OOP) is a programming language model organized around "objects" rather than "actions" and data rather than logic. Historically, a program has been viewed as a logical procedure that takes input data, processes it, and produces output data
Why OOP? 1. Object-oriented systems can be easily upgraded from small to large scale. 2. It is easy to partition the work in a project based on objects. 3. Object-oriented programming offers a new and powerful model for writing computer software. 4. It reduces software maintenance and developing costs. 5. Changes in user requirements or later developments have always been a major problem. 6. Object-orientation or object oriented programming (OOP) should help one in developing high quality software easily.
Concept of Class and Object • “Class” refers to a blueprint. It defines the variables and methods the objects support • “Object” is an instance of a class. Each object has a class which defines its data and behavior
Concept of Class and Object
Classes reflect concepts, objects reflect instances that embody those concepts object
Jodie
class
Daria
Jane
girl
Brittany
Class:A class can have three kinds of members:
Attribute/Field/Data
Method
Field Declaration • a type name followed by the field name, and optionally an initialization clause • primitive data type vs. Object reference o
boolean, char, byte, short, int, long, float, double
• field declarations can be preceded by different modifiers o o o
access control modifiers static final
Acces Control Modifier 1.private: private members are accessible only in the class itself 2.package: package members are accessible in classes in the same package and the class itself 3.protected: protected members are accessible in classes in the same package, in subclasses of the class, and in the class itself 4.public: public members are accessible anywhere the class is accessible
com Person MainMenu
• name: String • address: String # age: int +getName(): String
X
X
Employee
HRD
Pencil.java
public class Pencil { public String color = “red”; public int length; public float diameter; private float price; public static long nextID = 0; public void setPrice (float newPrice) { price = newPrice; } }
CreatePencil.java public class CreatePencil {
public static void main (String args[]){ Pencil p1 = new Pencil(); p1.price = 0.5f; }
} %> javac Pencil.java %> javac CreatePencil.java CreatePencil.java:4: price has private access in Pencil p1.price = 0.5f; ^