Java Programing laungage

class is a collection of similar type of object .A class is a blue print for the object, that blueprint describes the each object behaviors and state variable.

A class represent ADT(Abstract Data Type). It acts like a template using which we can create multiple objects. A class Declaration only create a template, it does not create an actual object . A class creates a new data type that can be used to create object. That a class creates a logical framework that defines the relationship between its member. when we declare an object of a class, we are creating an instance of that class. thus a class is a logical construct. An object has physically reality.

Declaration of class:

Access modifiers( public)( abstract | final) class class_name extends
	MySuperClass implements YourInterface
{
	// behaviors and state variables are declared between the { and } characters
}

1. Modifiers declare whether the class is public, abstract, or final.
2. The class declaration must contain the class keyword and the class name of the class that you are defining.
3. The class name, with the initial letter capitalized by convention (Title case).
4. The name of the superclass, if any, preceded by the keyword extends. A class can only extend one subclass.
5. The name of the interfaces implemented by the class, if any, preceded by the keyword implements.
6. A class can implement more than one interface.
7. The class body, surrounded by braces, {}.

Example :

import java.util.Scanner;
    class B
    {
		private int x;
		private float y;
        void getData()//for user input
        {
             Scanner sc;
             sc=new Scanner(System.in);
             System.out.print("Enter Value Of x :");
             x=sc.nextInt();
             System.out.print("Enter value of y :");
             y=sc.nextFloat();
         } 
         void setdata(int x1,float y1)//for testing purpose
         {
                    x=x1;
                    y=y1;
         }
         void display()
         {
                            System.out.println(x+","+y);
         }
    }
    class BTest
    {
         public static void main(String args[])
		{ 
              B a1,a2;
              a1=new B();
              a2=new B();
              //a1.x=5 ;//error
              //a1.getdata();
              //a2.gatdata();
              a1.setdata(10,10.5f);
              a2.setdata(2,5.4f);
              a1.display();
              a2.display();
         }
  }

output :

10,10.5
 2,5.4