Programming with Objects and Classes
) OO Programming Concepts
) Declaring and Creating Objects
) Constructors
) Modifiers (public, private and static)
) Instance and Class Variables and Methods
) Scope of Variables
) Use the this Keyword
) Analyze Relationships among Classes
) Case Studies (Mortgage class and Rational class)
) The Java API and Core Java classes
) Processing Strings (String, StringBuffer, and
StringTokenizer)
, OO Programming Concepts
• Classes are blueprints or structures for defining objects
• Each object is an instance of class
• In Java, each object has data which are used to describe
properties, and methods which are used to describe behaviors
• Each Java file is a class
Class object
, OO Programming Concepts
Class construction Data member1
Data member2
properties
…
Data memberN
Method1
behaviors
Method2
…
MethodM
, Class and Objects
Circle class
Circle Graphical
notation for
radius classes
findArea
new Circle() new Circle()
circle1: Circle circlen: Circle Graphical
notation for
radius = 2 ... radius = 5 objects