NAME – Akash chakraborty
STUDENT ID – 161001102037
STREAM – iMCA2
SEMESTER – 8TH
SUBJECT – OOP IN JAVA LAB ASSIGNMENT
1. Write a java program to draw different patterns.
import java.util.*;
class Pattern{
public static void main(String args[]){
Scanner s=new Scanner(System.in);
int n,i,j;
System.out.println("Enter a number:");
n=s.nextInt();
for(i=0;i<n;i++){
for(j=0;j<=i;j++)
System.out.print("*");
System.out.println(" ");
}
}
}
Output:
import java.util.*;
class Pattern1{
public static void main(String args[]){
Scanner s=new Scanner(System.in);
int n,i,j,k;
System.out.println("Enter a number:");
n=s.nextInt();
for(i=0;i<n;i++){
for(k=30-i;k>n;k--)
System.out.print(" ");
for(j=0;j<=2*i;j++)
System.out.print("*");
System.out.println(" ");
}
}
}
Output:
2. Write a java program to implement menu driven calculator.
import java.util.*;
class Menu{
int result;
public static void main(String args[]){
Scanner s=new Scanner(System.in);
System.out.println("Enter two numbers:");
int a=s.nextInt();
int b=s.nextInt();
System.out.println("For Addition press 1");
System.out.println("For Subtraction press 2");
System.out.println("For Multiplication press 3");
System.out.println("For Division press 4");
System.out.println("For Exit press 9");
System.out.println("Enter choice:");
int ch=s.nextInt();
int result;
switch(ch){
case 1:
result=a+b;
System.out.println("Result of addition="+result);
break;
case 2:
result=a-b;
System.out.println("Result of subtraction="+result);
break;
case 3:
result=a*b;
System.out.println("Result of multiplication="+result);
break;
case 4:
result=a/b;
System.out.println("Result of multiplication="+result);
break;
case 9:
System.out.println("Thanks for watching:");
System.exit(0);
break;
default:
System.out.println("Wrong choice...enter again");
break;
}
}
}
Output:
3. Write a java program to calculate area of a box by using dot
operator.
class Area1{
public double length, width;
public static void main(String args[]){
Area1 a=new Area1();
Area1 b=new Area1();
a.length=10.2;
b.length=19;
a.width=31.3;
b.width=24.5;
double a1=a.length*a.width;
double a2=b.length*b.width;
System.out.println("Area of box a is="+a1);
System.out.println("Area of box b is="+a2);
}
}
Output:
4. Write a java program to calculate area of a box by using a
method.
class Area{
double l,w,area;
void cal(double x,double y){
l=x;
w=y;
area=l*w;
}
void display(){
System.out.println("Area of the box="+area);
}
public static void main(String args[]){
Area a=new Area();
Area b=new Area();
a.cal(4.7,5.7);
b.cal(3.7,8.4);
b.display();
a.display();
}
}
Output:
5. Write a java program to calculate area of a box by using
constructor.
class Box{
double len,br;
Box(double x,double y)
len=x;
br=y;
Box(double x){
len=x;
br=x;
void display()
double area;
area=len*br;
System.out.println("Area of the box:"+area);
class RoomTest{
public static void main(String args[ ]){
Box a=new Box(10.5,12.2);
Box b=new Box(15.5);
a.display();
b.display();
Output:
6. Write a java program to store and display information about
students by using scanner class.
import java.util.*;
class Information{
public static void main(String args[]){
String name;
int roll_no,phy,math,eng,ben,che;
Scanner s=new Scanner(System.in);
System.out.println("Enter the Student name:");
name=s.nextLine();
System.out.println("Enter the Student roll_no:");
roll_no=s.nextInt();
System.out.println("Enter the marks of 5 subject of the Student:");
phy=s.nextInt();
math=s.nextInt();
eng=s.nextInt();
ben=s.nextInt();
che=s.nextInt();
double total=phy+math+eng+ben+che;
double p=total/500*100;
System.out.println("Display the details of the student:");
System.out.println("Student
name="+name+"\troll_no="+roll_no+"\tTotal="+total+"\tPercentage="+p);
}
}
Output:
7. Write a java program to implement command line argument.
class Command{
public static void main(String x[]){
int i;
for(i=0;i<x.length;i++){
System.out.println("The elements of args["+i+"] ="+x[i]);
Output:
8. Write a java program to perform addition of two numbers by
using scanner class.
import java.util.*;
class Add{
public static void main(String args[]){
Scanner s=new Scanner(System.in);
System.out.println("Enter 1st number:");
int a=s.nextInt();
System.out.println("Enter 2nd number:");
int b=s.nextInt();
int result=a+b;
System.out.println("Addition="+result);
Output:
9. Write a java program to implement constructor overloading.
class Room{
double len,wid;
Room(){
len=0;
wid=0;
}
Room(double x,double y){
len=x;
wid=y;
}
Room(double x){
len=x;
wid=x;
}
void display(){
double area=len*wid;
System.out.println("Area of a Room="+area);
}
}
class Constructor{
public static void main(String args[]){
Room b=new Room();
Room c=new Room(3);
Room d=new Room(2.7,8.4);
b.display();
c.display();
d.display();
}
}
Output:
10. Write a java program to implement method overloading.
class Over{
void volumn(double r,double h){
double v=3.14*(r*r)*h;
System.out.println("Volumn of the cylinder is = "+v);
}
void volumn(double r,int h){
double v=(3.14*(r*r)*h)/3;
System.out.println("Volumn of the circular cone is = "+v);
}
void volumn(double r){
double v=(4*3.14*(r*r*r))/3;
System.out.println("Volumn of the sphere is = "+v);
}
int volumn(int r){
return(r*r*r);
}
}
class Overload{
public static void main(String args[]){
Over o=new Over();
o.volumn(1.2,4);
o.volumn(5.2,4.3);
o.volumn(2.1);
int v=o.volumn(3);
System.out.println("Volumn of the cube is = "+v);
}
}
Output:
11. Write a java program to implement method overriding.
class A{
int a=2;
void show(){
System.out.println("The results of a="+a);
}
}
class B extends A{
int b=3;
void show(){
System.out.println("The results of b="+b);
}
}
class Override{
public static void main(String args[]){
B ob=new B();
A oc=new B();
A od=new A();
ob.show();
oc.show();
od.show();
}
}
Output:
12. Write a java program to implement single inheritance.
class A{
int a=2;
void showA(){
System.out.println("a="+(a+2));
}
}
class B extends A{
int b=6;
void showB(){
System.out.println("b="+(b*2));
}
}
class Single{
public static void main(String args[]){
B ob=new B();
ob.showA();
ob.showB();
}
}
Output:
13. Write a java program to implement multilevel inheritance.
class X
{
public void methodX()
{
System.out.println("class X method");
}
}
class Y extends X
{
public void methodY()
{
System.out.println("class Y method");
}
}
class Z extends Y
{
public void methodZ()
{
System.out.println("class Z method");
}
}
class Multilevel
{
public static void main(String args[])
{
Z obj = new Z();
obj.methodX();
obj.methodY();
obj.methodZ();
}
}
14. Write a java program to implement hierarchical inheritance.
class E{
int a,b;
void addE(int x,int y){
a=x;
b=y;
int s=a+b;
System.out.println("Sum ="+s);
}
}
class F extends E{
void showF(){
System.out.println("method of F class");
}
}
class G extends E{
void showG(){
System.out.println("method of G class");
}
}
class H extends E{
void showH(){
System.out.println("method of H class");
}
}
class Hierarchical{
public static void main(String args[]){
F f=new F();
G g=new G();
H h=new H();
f.showF();
f.addE(12,14);
g.showG();
g.addE(42,13);
h.showH();
h.addE(6,52);
}
}
Output:
15. Write a java program to implement multiple inheritance.
class Student
{
String name;
int roll;
Student(String n, int r)
{
name=n;
roll=r;
}
void show()
{
System.out.println("Name is: " +name);
System.out.println("Roll is: " +roll);
}
}
class Test extends Student
{
int part1,part2;
Test(String n, int r, int p1, int p2)
{
super(n, r);
part1=p1;
part2=p2;
}
void show()
{
super.show();
System.out.println("Marks of part1: " +part1);
System.out.println("Marks of part2: " +part2);
}
}
interface Sports
{
int score=10;
void showSports();
}
class Result extends Test implements Sports
{
int total;
Result (String n, int r, int p1, int p2)
{
super (n,r,p1,p2);
total = part1 + part2 + score;
}
public void showSports()
{
System.out.println("Score in Sports: " +score);
}
void show()
{
super.show();
showSports();
System.out.println("Total is: " +total);
}
}
class TestResult
{
public static void main(String args[])
{
Result r = new Result("Niru", 06, 73, 74);
r.show();
}
}
16. Write a java program to implement hybrid inheritance.
class C
{
public void disp()
{
System.out.println("C");
}
}
class A extends C
{
public void disp()
{
System.out.println("A");
}
}
class B extends C
{
public void disp()
{
System.out.println("B");
}
}
class D extends A
{
public void disp()
{
System.out.println("D");
}
}
class Hybrid
{
public static void main(String args[])
{
D obj = new D();
obj.disp();
}
}
OUTPUT:-
17. Write a java program to implement abstract class.
abstract class P{
int p;
int m;
public P(){
p=2;
m=6;
}
abstract void f();
void display(){
System.out.println(p);
System.out.println(m=m+2);
}
}
abstract class Q extends P{
abstract void f1();
}
class R extends Q{
int r;
public R(){r=3;}
void f(){
System.out.println("In class R "+r);
}
void f1(){
System.out.println("In class R from Q");
}
}
class TestAbs{
public static void main(String ar[]){
R or=new R();
or.f();
or.f1();
or.display();
}
}
Output:
18. Write a java program to implement interface.
interface I1{
public static final int x=5;
public static final int y=10;
public abstract void m();
}
interface I2 extends I1{
public static final int z=7;
public abstract void m1();
}
class A implements I2{
int a=4;
int c;
void get_a()
{
System.out.println(a);
}
public void m(){
c=x+y;
System.out.println(c);
System.out.println(y);
}
public void m1(){
System.out.println(z);
}
}
class TextB extends A{
public static void main(String args[]){
TextB ob=new TextB();
System.out.println("Output are..");
ob.get_a();
ob.m();
ob.m1();
System.out.println(x);
}
}
Output:
19. Write a java program to implement try catch.
class Excep1{
public static void main(String args[]){
try{
int n=Integer.parseInt(args[0]);
int n1=Integer.parseInt(args[1]);
int n2=n+n1;
System.out.println("addition="+n2);
}
catch(Exception ex){
System.out.println(ex);
}
}
}
Output:
20. Write a java program to implement multiple try catch.
import java.util.*;
class Excep2{
public static void main(String args[]){
try{
Scanner s=new Scanner(System.in);
int a,b,c,ar;
int arr[]={6,8,9};
System.out.println("Enter a,b:");
a=s.nextInt();
b=s.nextInt();
c=a/b;
System.out.println("division is "+c);
ar=arr[0]+arr[5];
}
catch(ArithmeticException ex){
System.out.println("Arithmetic Exception :"+ex.getMessage());
}
catch(NumberFormatException ex){
System.out.println("Format Exception :"+ex.getMessage());
}
catch(Exception ex){
System.out.println("Exception :"+ex);
}
}
}
Output:
21. Write a java program to implement use of throws.
import java.io.*;
class Testthrows{
void m()throws IOException{
throw new IOException("Device error");
}
void n()throws IOException{
m();
}
void p(){
try{
n();}
catch(Exception e){
System.out.println("Exception handled");}
}
public static void main(String args[]){
Testthrows obj=new Testthrows();
obj.p();
System.out.println("Normal flow...");
}
}
Output:
22. Write a java program to implement user defined exception.
import java.lang.Exception;
class MyException extends Exception{
MyException(String message){
super(message);
}
}
class TestMyException{
public static void main(String args[]){
int x=5,y=1000;
try{
float z=(float) x/(float) y;
if(z<0.01){
throw new MyException("Number is too small");
}
}
catch(MyException e){
System.out.println("Caught my exception");
System.out.println(e.getMessage());
}
finally{
System.out.println("I am always here");
}
}
}
Output:
23. Write a java program to implement user defined package.
/*package treepackage;
public class tree
{
public void disp()
{
int i,j,k,l;
for(i=1;i<=5;i++)
{
for(j=5;j>=i;j?)
{
System.out.print(? ?);
}
for(k=1;k<=i;k++)
{
System.out.print(?*?);
}
for(l=i-1;l>=1;l?)
{
System.out.print(?*?);
}
System.out.print(?\n?);
}}
public void root()
{
int k,i,j;
for( i=1;i<=5;i++)
-{
for( j=1;j<5;j++)
{
System.out.print(? ?);
}
for(k=1;k<=3;k++)
{
System.out.print(?*?);
}
System.out.println(? ?);
}
}
}//Save this package as tree.java
*/
import treepackage.tree;
class UserDefinedPackageDemo{
public static void main(String args[]){
UserDefinedPackageDemo obj=new UserDefinedPackageDemo();
obj.disp();
obj.disp();
obj.disp();
obj.disp();
obj.root();
}
}Sample Output
Output is:
*
***
*****
*******
*********
*
***
*****
*******
*********
*
***
*****
*******
*********
*
***
*****
*******
*********
***
***
***
***
***
24. Write a java program to implement different string class
method.
import java.io.*;
class TR2{
public static void main(String args[]){
try{
File f=new File("TestA.txt");
BufferedReader br=new BufferedReader(new FileReader(f));
String st=br.readLine();
System.out.println(st);
PrintWriter pw=new PrintWriter(new FileWriter(f,true));
pw.write("..Welcome to tamluk");
pw.close();
System.out.println("after write");
br=new BufferedReader(new FileReader(f));
st=br.readLine();
System.out.println(st);
}catch(Exception ie){System.out.println(ie);}
}
}
Output:
25. Write a java program to implement sorting of 10 integer
numbers.
import java.util.*;
class BubbleSort{
void cal(int a[],int n){
int temp=0;
for(int i=0;i<n-1;i++){
for(int j=0;j<n-i-1;j++){
if(a[j]>a[j+1]){
temp=a[j];
a[j]=a[j+1];
a[j+1]=temp;
}
}
}
}
void display(int a[],int n){
System.out.println();
System.out.println("After sorting the results will be:");
System.out.println();
for(int i=0;i<n;i++){
System.out.print("\t"+a[i]);
}
}
}
class Sort2{
public static void main(String args[]){
Scanner s=new Scanner(System.in);
int a[],n;
System.out.println("Enter how many array elements will be present:");
n=s.nextInt();
a=new int [n];
System.out.println("Enter "+n+" array elements:");
for(int i=0;i<n;i++){
a[i]=s.nextInt();
}
System.out.println("Before sorting the array elements are:");
System.out.println();
for(int i=0;i<n;i++){
System.out.print("\t"+a[i]);
}
BubbleSort ob=new BubbleSort();
ob.cal(a,n);
ob.display(a,n);
}
}
Output:
26. Write a java program to display string by using applet.
import java.awt.*;
import java.applet.*;
public class AppletHelloJava extends Applet
{
public void init()
{
setBackground(Color.YELLOW);
setForeground(Color.RED);
}
public void paint (Graphics g)
{
g.drawString("Hello java", 20, 30);
}
}
Compile:-
Javac AppletHelloJava.java
Run:-
Java AppletHelloJava
27.) Write a java program to draw a line.
import java.awt.*;
import javax.swing.*;
import java.awt.geom.Line2D;
class MyCanvas extends JComponent {
public void paint(Graphics g)
{
// draw and display the line
g.drawLine(30, 20, 80, 90);
}
}
public class GFG1 {
public static void main(String[] a)
{
// creating object of JFrame(Window popup)
JFrame window = new JFrame();
// setting closing operation
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// setting size of the pop window
window.setBounds(30, 30, 200, 200);
// setting canvas for draw
window.getContentPane().add(new MyCanvas());
// set visibility
window.setVisible(true);
}
}
Output :
28.) Write a java program to draw a triangle.
import java.lang.*;
import java.util.*;
import java.util.List;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
public class DrawTriangle extends Frame {
public Polygon mypolygon = new Polygon();
public void paint(Graphics g) {
Graphics2D ga = (Graphics2D)g;
ga.setPaint(Color.red);
ga.drawPolygon(mypolygon);
}
public static void main(String args[]) {
List< Integer > srcpoints = new ArrayList< Integer >();
srcpoints.add(200);srcpoints.add(200);
srcpoints.add(75);srcpoints.add(75);
srcpoints.add(100);srcpoints.add(200);
srcpoints.add(srcpoints.get(0));
srcpoints.add(srcpoints.get(1));
DrawTriangle frame = new DrawTriangle();
for(int i = 0; i < srcpoints.size(); i++)
{
int x = srcpoints.get(i++);
int y = srcpoints.get(i);
frame.mypolygon.addPoint(x, y);
}
frame.addWindowListener(
new WindowAdapter()
{
public void windowClosing(WindowEvent we)
{
System.exit(0);
}
}
);
frame.setSize(400, 400);
frame.setVisible(true);
}
}
Output
29) Write a java program to create child thread from main thread.
public class Test extends Thread
{
public static void main(String[] args)
{
Thread t = Thread.currentThread();
System.out.println("Current thread: " + t.getName());
t.setName("Geeks");
System.out.println("After name change: " + t.getName());
System.out.println("Main thread priority: "+ t.getPriority());
t.setPriority(MAX_PRIORITY);
System.out.println("Main thread new priority: "+ t.getPriority());
for (int i = 0; i < 5; i++)
{
System.out.println("Main thread");
}
ChildThread ct = new ChildThread();
System.out.println("Child thread priority: "+ ct.getPriority());
ct.setPriority(MIN_PRIORITY);
System.out.println("Child thread new priority: "+ ct.getPriority());
ct.start();
}
}
class ChildThread extends Thread
{
@Override
public void run()
{
for (int i = 0; i < 5; i++)
{
System.out.println("Child thread");
}
}
}
Output:
Current thread: main
After name change: Geeks
Main thread priority: 5
Main thread new priority: 10
Main thread
Main thread
Main thread
Main thread
Main thread
Child thread priority: 10
Child thread new priority: 1
Child thread
Child thread
Child thread
Child thread
Child thread
30.) Write a java program to implement thread by runnable interface.
class Multi3 implements Runnable
{
public void run()
{
System.out.println("thread is running...");
}
public static void main(String args[])
{
Multi3 m1 = new Multi3();
Thread t1 = new Thread(m1);
t1.start();
}
}
OUTPUT:-
thread is running………
