Experiment No:$1$ IMPLEMENTATION OF INHERITANCE

AIM: Write a Java Program to implement multilevel inheritance by applying various access controls to

its data members and methods.

DESCRIPTION:

The base class Student provides methods to read details of students. The class Marks is inherited from

Student which possesses methods to accept and prints marks of student. Class Result is derived from

class Marks which computes the result.

ALGORITHM:

$1.$ Create base class Student and define its methods.

$2.$ Derive class Marks from Student and define its data members and methods

$3.$ Derive subclass Result from Marks and define its data members and methods.

$4.$ Create objects of class Result.

$5.$ Invoke appropriate methods using the created object.

$6.$ Stop.

PROGRAM

import java.io$.$DataInputStream;

class Student

$\{$

private int rollno;

private String name;

DataInputStream dis$=$new DataInputStream$($System$.$in$)$;

public void getrollno$()$

$\{$

try $\{$

System.out.println$("$Enter rollno $")$;

rollno$=$Integer.parseInt$($dis$.$readLine$())$;

System.out.println$("$Enter name $")$;

name$=$dis.readLine$()$;

$\}$

catch$($Exception e$)\{\}$

$\}$

void putrollno$()$

$\{$

System.out.println$("$Roll No $="+$rollno$)$;

System.out.println$("$Name $="+$name$)$;

$\}$

$\}$

class Marks extends Student

$\{$

protected int m$1,$m$2,$m$3$;

void getmarks$()$

$\{$

try

$\{$

System.out.println$("$Enter marks :$")$;

m$1=$Integer.parseInt$($dis$.$readLine$())$;

m$2=$Integer.parseInt$($dis$.$readLine$())$;

m$3=$Integer.parseInt$($dis$.$readLine$())$;

$\}$

catch$($Exception e$)\{\}$

$\}$

void putmarks$()$

$\{$

System.out.println$("$m$1="+$m$1)$;

System.out.println$("$m$2="+$m$2)$; System.out.println$("$m$3="+$m$3)$;

$\}$

$\}$

class Result extends Marks

$\{$

private float total;

void compute$\_$display$()$

$\{$

total$=$m$1+$m$2+$m$3$;

System.out.println$("$Total marks :$"+$total$)$;

$\}$

$\}$

class Multilevel

$\{$

public static void main$($String arg$[])$

$\{$

Result r$=$new Result$()$;

r$.$getrollno$()$;

r$.$getmarks$()$;

r$.$putrollno$()$;

r$.$putmarks$()$;

r$.$compute$\_$display$()$;

$\}$

$\}$

SAMPLE OUTPUT

C:$\backslash$jdk$1\mathrm{.}6\mathrm{.}0\_26\backslash$bin$>$javac Multilevel.java

Note: Multilevel.java uses or overrides a deprecated API.

Note: Recompile with $$Xlint:deprecation for details.

C:$\backslash$jdk$1\mathrm{.}6\mathrm{.}0\_26\backslash$bin$>$java Multilevel

Enter rollno $12345$

Enter name

Avinash

Enter marks :

$54$

$78$

$46$

Roll No $=12345$

Name $=$Avinash

m$1=54$

m$2=78$

m$3=46$

Total marks :$178\mathrm{.}0$