1. Write a program to find greatest among 3 numbers using nested if-else.
import java.util.Scanner;
public class GreatestAmongThree {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.println("Enter three numbers: ");
int a = scanner.nextInt();
int b = scanner.nextInt();
int c = scanner.nextInt();
if (a > b) {
if (a > c) {
System.out.println("Greatest number is: " + a);
} else {
System.out.println("Greatest number is: " + c);
}
} else {
if (b > c) {
System.out.println("Greatest number is: " + b);
} else {
System.out.println("Greatest number is: " + c);
}
}
}
}
2. Write a program to check if user entered password contains Uppercase, Lowercase, and no. Characters
using logical operators.
import java.util.Scanner;
public class PasswordChecker {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.println("Enter your password: ");
String password = scanner.nextLine();
boolean hasUpperCase = false;
boolean hasLowerCase = false;
boolean hasNumber = false;
for (char c : password.toCharArray()) {
if (Character.isUpperCase(c)) {
hasUpperCase = true;
} else if (Character.isLowerCase(c)) {
hasLowerCase = true;
} else if (Character.isDigit(c)) {
hasNumber = true;
}
}
if (hasUpperCase && hasLowerCase && hasNumber) {
System.out.println("Password is valid.");
} else {
System.out.println("Password is invalid. Make sure it contains uppercase, lowercase, and
numeric characters.");
}
}
}
3. Write any program to check switch-case statement using character datatype.
public class SwitchCaseChar {
public static void main(String[] args) {
char grade = 'B';
switch (grade) {
case 'A':
System.out.println("Excellent!");
break;
case 'B':
System.out.println("Good!");
break;
case 'C':
System.out.println("Fair!");
break;
case 'D':
System.out.println("Needs Improvement!");
break;
default:
System.out.println("Invalid Grade!");
}
}
}
4. Develop a program to print command line argument using for loop.
public class CommandLineArguments {
public static void main(String[] args) {
for (int i = 0; i < args.length; i++) {
System.out.println(args[i]);
}
}
}
5. Write a program to display the following star pattern using for loop.
*
**
***
****
public class StarPattern {
public static void main(String[] args) {
int rows = 5;
for (int i = 1; i <= rows; i++) {
for (int j = 1; j <= i; j++) {
System.out.print("*");
}
System.out.println();
}
}
}
6. Write a program to display multiplication table of 7 using do-while loop.
public class MultiplicationTableSeven {
public static void main(String[] args) {
int num = 7;
int i = 1;
do {
System.out.println(num + " x " + i + " = " + (num * i));
i++;
} while (i <= 10);
}
}
7. Write a program to implicitly typecast lower range data type to larger storage size data type.
public class TypeCasting {
public static void main(String[] args) {
int numInt = 100;
long numLong = numInt;
float numFloat = numLong;
System.out.println("Integer value: " + numInt);
System.out.println("Implicitly casted to long: " + numLong);
System.out.println("Implicitly casted to float: " + numFloat);
}
}
8. Write a program to convert variable of basic data types and shows result of explicit typecasting.
public class TypeCastingExplicit {
public static void main(String[] args) {
double numDouble = 10.5;
int numInt = (int) numDouble;
long numLong = (long) numDouble;
System.out.println("Double value: " + numDouble);
System.out.println("Explicitly casted to int: " + numInt);
System.out.println("Explicitly casted to long: " + numLong);
}
}
9. Write a program to perform constructor overloading.
public class ConstructorOverloading {
private int value;
// Default constructor
public ConstructorOverloading() {
this.value = 0;
}
// Parameterized constructor
public ConstructorOverloading(int value) {
this.value = value;
}
public int getValue() {
return value;
}
public static void main(String[] args) {
ConstructorOverloading obj1 = new ConstructorOverloading();
ConstructorOverloading obj2 = new ConstructorOverloading(10);
System.out.println("Value of obj1: " + obj1.getValue());
System.out.println("Value of obj2: " + obj2.getValue());
}
}
10. Write a program to show the use any 6 methods of string class.
public class StringMethods {
public static void main(String[] args) {
String str = "Hello, World!";
System.out.println("Length: " + str.length());
System.out.println("Substring: " + str.substring(7));
System.out.println("Index of 'o': " + str.indexOf('o'));
System.out.println("Uppercase: " + str.toUpperCase());
System.out.println("Lowercase: " + str.toLowerCase());
System.out.println("Replace: " + str.replace("World", "Java"));
}
}
11. Write a program to use 4 methods string buffer class.
public class StringBufferMethods {
public static void main(String[] args) {
StringBuffer buffer = new StringBuffer("Hello");
System.out.println("Initial Buffer: " + buffer);
buffer.append(" World");
System.out.println("Appended Buffer: " + buffer);
buffer.insert(6, ", Java");
System.out.println("Inserted Buffer: " + buffer);
buffer.delete(5, 10);
System.out.println("Deleted Buffer: " + buffer);
buffer.reverse();
System.out.println("Reversed Buffer: " + buffer);
}
}
12. Write a program to implement 3 X 3 matrix multiplication.
public class MatrixMultiplication {
public static void main(String[] args) {
int[][] matrix1 = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
int[][] matrix2 = {{9, 8, 7}, {6, 5, 4}, {3, 2, 1}};
int[][] result = new int[3][3];
// Perform matrix multiplication
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
for (int k = 0; k < 3; k++) {
result[i][j] += matrix1[i][k] * matrix2[k][j];
}
}
}
// Display the result
System.out.println("Resultant Matrix:");
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
System.out.print(result[i][j] + " ");
}
System.out.println();
}
}
}
13. Write a program to display elements of array using for-each loop.
public class DisplayArray {
public static void main(String[] args) {
int[] array = {1, 2, 3, 4, 5};
for (int element : array) {
System.out.print(element + " ");
}
}
}
14. Write a program to insert different elements in the vector and display it.
import java.util.Vector;
public class VectorExample {
public static void main(String[] args) {
Vector<Integer> vector = new Vector<>();
// Inserting elements into the vector
vector.add(10);
vector.add(20);
vector.add(30);
vector.add(40);
// Displaying elements of the vector
System.out.println("Elements of the vector:");
for (int i = 0; i < vector.size(); i++) {
System.out.println(vector.get(i));
}
}
}
15. Write a program to convert
(I) Primitive data type into string object
(II) String value into Integer Wrapper class object.
public class TypeConversion {
public static void main(String[] args) {
// (I) Primitive data type to string object
int num = 10;
String str = Integer.toString(num);
System.out.println("String representation of primitive data type: " + str);
// (II) String value into Integer Wrapper class object
String numberStr = "100";
Integer integerObj = Integer.valueOf(numberStr);
System.out.println("Integer wrapper class object: " + integerObj);
}
}
16. Develop a program to extend ‘dog’ from ‘animal’ to override ‘move()’ method using super keyword.
class Animal {
void move() {
System.out.println("Animals can move");
}
}
class Dog extends Animal {
void move() {
super.move(); // Calling move() method of super class
System.out.println("Dogs can walk and run");
}
}
public class SuperExample {
public static void main(String[] args) {
Dog dog = new Dog();
dog.move(); // This will call overridden move() method of Dog class
}
}
17. Write a program to display rate of interest of bank using method overriding.
class Bank {
double getRateOfInterest() {
return 0;
}
}
class SBI extends Bank {
@Override
double getRateOfInterest() {
return 7.5;
}
}
class ICICI extends Bank {
@Override
double getRateOfInterest() {
return 8.0;
}
}
public class MethodOverridingExample {
public static void main(String[] args) {
SBI sbi = new SBI();
ICICI icici = new ICICI();
System.out.println("Rate of interest in SBI: " + sbi.getRateOfInterest());
System.out.println("Rate of interest in ICICI: " + icici.getRateOfInterest());
}
}
18. Write a program to calculate area and volume of room using single inheritance.
class Room {
double length;
double width;
Room(double length, double width) {
this.length = length;
this.width = width;
}
double calculateArea() {
return length * width;
}
}
class Room3D extends Room {
double height;
Room3D(double length, double width, double height) {
super(length, width);
this.height = height;
}
double calculateVolume() {
return length * width * height;
}
}
public class SingleInheritanceExample {
public static void main(String[] args) {
Room3D room = new Room3D(10, 5, 3);
System.out.println("Area of the room: " + room.calculateArea());
System.out.println("Volume of the room: " + room.calculateVolume());
}
}
19. Develop a program for implementation of multiple inheritance using interface.
interface A {
void methodA();
}
interface B {
void methodB();
}
class MyClass implements A, B {
public void methodA() {
System.out.println("Method A");
}
public void methodB() {
System.out.println("Method B");
}
}
public class MultipleInheritanceExample {
public static void main(String[] args) {
MyClass obj = new MyClass();
obj.methodA();
obj.methodB();
}
}
20. Define a package named ‘College’ include class named as ‘Dept’ with one method to display the name
of the department. Develop a program to import this package in a java application and call the method
defined in the package.
// College/Dept.java
package College;
public class Dept {
public void displayDepartment() {
System.out.println("Computer Science Department");
}
}
// Importing package in Java application
import College.Dept;
public class PackageImportExample {
public static void main(String[] args) {
Dept department = new Dept();
department.displayDepartment();
}
}
21. Develop a program to implement multithreading by creating two threads “even” and “odd”.
public class EvenOddThread {
public static void main(String[] args) {
EvenThread evenThread = new EvenThread();
OddThread oddThread = new OddThread();
evenThread.start();
oddThread.start();
}
}
class EvenThread extends Thread {
public void run() {
for (int i = 2; i <= 10; i += 2) {
System.out.println("Even: " + i);
try {
Thread.sleep(1000); // Sleep for 1 second
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
class OddThread extends Thread {
public void run() {
for (int i = 1; i <= 10; i += 2) {
System.out.println("Odd: " + i);
try {
Thread.sleep(1000); // Sleep for 1 second
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
22. Write a program to implement the different priorities in multithreading.
public class ThreadPriorityExample {
public static void main(String[] args) {
Thread t1 = new Thread(new MyThread(), "Thread 1");
Thread t2 = new Thread(new MyThread(), "Thread 2");
// Setting priorities
t1.setPriority(Thread.MIN_PRIORITY);
t2.setPriority(Thread.MAX_PRIORITY);
t1.start();
t2.start();
}
}
class MyThread implements Runnable {
public void run() {
for (int i = 0; i < 5; i++) {
System.out.println(Thread.currentThread().getName() + ": " + i);
try {
Thread.sleep(500); // Sleep for 0.5 seconds
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
23. Develop a program to catch “DivideByZeroException”.
public class DivideByZeroExceptionExample {
public static void main(String[] args) {
int numerator = 10;
int denominator = 0;
try {
int result = numerator / denominator;
System.out.println("Result: " + result);
} catch (ArithmeticException e) {
System.out.println("Error: " + e.getMessage());
}
}
}
24. Define a Exception called “NotMatchException” that is thrown when a string is not equal to “msbte”.
Write a program that uses this exception.
import java.io.*;
class NoMatchException extends Exception
{
NoMatchException(String s)
{
super(s);
}
}
class test1
{
public static void main(String args[]) throws IOException
{
BufferedReader br= new BufferedReader(new InputStreamReader(System.in) );
System.out.println("Enter a word:");
String str= br.readLine();
try
{
if (str.compareTo("MSBTE")!=0) // can be done with equals()
throw new NoMatchException("Strings are not equal");
else
System.out.println("Strings are equal");
}
catch(NoMatchException e)
{
System.out.println(e.getMessage());
}
}
}
25. Develop a basic applet to display “Welcome to the world of Applet”.
import java.applet.Applet;
import java.awt.Graphics;
public class WelcomeApplet extends Applet {
public void paint(Graphics g) {
g.drawString("Welcome to the world of Applet", 50, 50);
}
}
<!DOCTYPE html>
<html>
<head>
<title>Applet Example</title>
</head>
<body>
<applet code="WelcomeApplet.class" width="300" height="200">
</applet>
</body>
</html>
26. Develop a program to accept username and password and check if password is greater than 8 letters
using <param> tag.
import java.applet.Applet;
import java.awt.Graphics;
public class PasswordApplet extends Applet {
String username, password;
public void init() {
username = getParameter("username");
password = getParameter("password");
if (password.length() > 8) {
System.out.println("Password length is greater than 8 characters.");
} else {
System.out.println("Password length is not greater than 8 characters.");
}
}
public void paint(Graphics g) {
g.drawString("Username: " + username, 50, 50);
g.drawString("Password: " + password, 50, 70);
}
}
<!DOCTYPE html>
<html>
<head>
<title>Password Applet</title>
</head>
<body>
<applet code="PasswordApplet.class" width="300" height="200">
<param name="username" value="john">
<param name="password" value="password123">
</applet>
</body>
</html>
27. Write a program to draw a polygon.
import java.awt.*;
import javax.swing.*;
public class PolygonDrawing extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
int[] xPoints = {50, 100, 150, 100};
int[] yPoints = {50, 100, 50, 0};
int nPoints = 4;
g.drawPolygon(xPoints, yPoints, nPoints);
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new PolygonDrawing());
frame.setSize(200, 200);
frame.setVisible(true);
}
}
28. Write a program to draw circle inside a square.
import java.awt.*;
import javax.swing.*;
public class CircleInSquare extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
int squareSize = 100;
int circleDiameter = 80;
int squareX = (getWidth() - squareSize) / 2;
int squareY = (getHeight() - squareSize) / 2;
g.drawRect(squareX, squareY, squareSize, squareSize);
g.drawOval(squareX + (squareSize - circleDiameter) / 2, squareY + (squareSize - circleDiameter)
/ 2, circleDiameter, circleDiameter);
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new CircleInSquare());
frame.setSize(200, 200);
frame.setVisible(true);
}
}
29. Develop a program to copy the content of one file into another.
import java.io.*;
public class FileCopy {
public static void main(String[] args) {
try {
FileReader source = new FileReader("source.txt");
FileWriter destination = new FileWriter("destination.txt");
int c;
while ((c = source.read()) != -1) {
destination.write(c);
}
source.close();
destination.close();
System.out.println("File copied successfully.");
} catch (IOException e) {
System.out.println("Error: " + e.getMessage());
}
}
}
30. Write a program to count the number of words in file.
import java.io.*;
public class WordCount {
public static void main(String[] args) {
try {
FileReader fileReader = new FileReader("input.txt");
BufferedReader bufferedReader = new BufferedReader(fileReader);
String line;
int wordCount = 0;
while ((line = bufferedReader.readLine()) != null) {
String[] words = line.split("\\s+");
wordCount += words.length;
}
bufferedReader.close();
System.out.println("Number of words in the file: " + wordCount);
} catch (IOException e) {
System.out.println("Error: " + e.getMessage());
}
}
}
