classes and objects in java with realtime examples

Class object and Method

The java program to dismonstrate the concept of Class,object and Method

• Step 1: Define a class by name Rectangle.
• Step 2: Declare Two Instance Variable Length and Width.
• Step 3: Declare and define Two Method Set Data and Call Area get Value and
•              to return area of Rectangle.
• Step 4: Define a Class Rectangle Demo.
• Step 5: Define a Main() and Create Object to rectangle Class.
• Step 5: The using Println()Show the Area of rectengle.

CLASS OBJECT AND METHOD

Program

class Rectangle
{
int length,width;
void setdata(int l, int w)
{
length=l;
width=w;
}
int calArea()
{
int area;
area=length * width;
return area;
}
}
class RectangleDemo
{
public staic void main (String args[])
{
Rectangle r1=new Rectangle();
r1.length=15;
r1.width=4;
System.out.println("Area of First Rectangle is ="+r1.length*r1.width);
Rectangle r2=new Rectangle();
r2.setData(5,3);
System.out.println("Area of Second Rectangle is ="+r2.calArea());
}
}

Output:

C:\class\java>javac RectangleDemo.java
C:\class\java>java RectangleDemo

Area of First Rectangle is=60
Area of Second Rectangle is =15

RESULT:
    Thus the program Succesfully Exected.