Object Oriented Programming (OOP) Aug 10th

print and println:

print------ cursor goes to the next line(similar to \n)

println---- Cursor remains in the same line

Class- In OOP a class is a template defination of methods and variables in a particularkind of objects.

Hence, we can say that class defines the structures and behaviors(data and code) that will be shared by a set of objects.

Objects- Object is the instance of class

A program from schieldt

/* A program that uses the Box class.

Call this file BoxDemo.java

*/

class Box {

double width;

double height;

double depth;

}

// This class declares an object of type Box.

class BoxDemo {

public static void main(String args[]) {

Box mybox = new Box();

double vol;

// assign values to mybox's instance variables

mybox.width = 10;

mybox.height = 20;

mybox.depth = 15;

// compute volume of box

vol = mybox.width * mybox.height * mybox.depth;

System.out.println("Volume is " + vol);

}

}

So, to create an object

Box mybox=new Box();

where Box() is the constructor or class name as both should be same.

statement and funtion:

Box mybox2=mybox; does not create an object rather a reference is created.

If we change the value of any parameters like width,height or depth by mybox2, then the change will also stay if we call by mybox.