Advanced Java online training

1
Class and Object in Java

• https//www.gangboard.com/app-programming-scriptin
  g-training/core-java-training

2
Class

• A class is a user defined blueprint or prototype
  from which objects are created.  
• It represents the set of properties or methods
  that are common to all objects of one type. In
  general, class declarations can include these
  components.

3
Class

• Modifiers  A class can be public or has default
  access.
• Class name The name should begin with a initial
  letter (capitalized by convention).
• Superclass(if any) The name of the classs
  parent (superclass), if any, preceded by the
  keyword extends.
• Interfaces(if any) A comma-separated list of
  interfaces implemented by the class, if any,
  preceded by the keyword implements.
• Body The class body surrounded by braces, .

4
Create a Class

• Create a Class called MyClass and a Variable x
• public class MyClass   int x  5

5
Object

• It is a basic unit of Object Oriented
  Programming and represents the real life
  entities.  
• A typical Java program creates many objects,
  which as you know, interact by invoking methods.

6
Object

• State  It is represented by attributes of an
  object. It also reflects the properties of an
  object.
• Behavior  It is represented by methods of an
  object. It also reflects the response of an
  object with other objects.
• Identity  It gives a unique name to an object
  and enables one object to interact with other
  objects.

7
Create an Object

• Create an Object called MyObj and print the
  value x
• public class MyClass   int x  5public static 
  void main(String args)     MyClass myObj  new
   MyClass()    System.out.println(myObj.x) 
  

8
Class and Object Difference

• A class is a blueprint or prototype that defines
  the variables and the methods (functions) common
  to all objects of a certain kind.