1.
Operators
public class BasicOperations {
public static void main(String[] args) {
int a = 10, b = 5;
System.out.println("Arithmetic Operations:");
System.out.println("a + b = " + (a + b));
System.out.println("a - b = " + (a - b));
System.out.println("a * b = " + (a * b));
System.out.println("a / b = " + (a / b));
System.out.println("a % b = " + (a % b));
System.out.println("\nRelational Operations:");
System.out.println("a == b: " + (a == b));
System.out.println("a != b: " + (a != b));
System.out.println("a > b: " + (a > b));
System.out.println("a < b: " + (a < b));
System.out.println("a >= b: " + (a >= b));
System.out.println("a <= b: " + (a <= b));
boolean x = true, y = false;
System.out.println("\nLogical Operations:");
System.out.println("x && y: " + (x && y));
System.out.println("x || y: " + (x || y));
System.out.println("!x: " + (!x));
System.out.println("\nBitwise Operations:");
System.out.println("a & b: " + (a & b));
System.out.println("a | b: " + (a | b));
System.out.println("a ^ b: " + (a ^ b));
System.out.println("~a: " + (~a));
System.out.println("\nUnary Operations:");
int c = 10;
System.out.println("Initial c = " + c);
System.out.println("++c = " + (++c));
System.out.println("--c = " + (--c));
System.out.println("c++ = " + (c++));
System.out.println("c-- = " + (c--));
System.out.println("Final c = " + c);
System.out.println("\nTernary Operation:");
int max = (a > b) ? a : b;
System.out.println("Max of a and b is: " + max);
System.out.println("\nShift Operations:");
System.out.println("a << 1: " + (a << 1));
System.out.println("a >> 1: " + (a >> 1));
System.out.println("a >>> 1: " + (a >>> 1));
2a.Salary
import java.util.Scanner;
public class GrossSalaryCalculator {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter Basic Salary (bs): ");
double bs = scanner.nextDouble();
double hra = 0, da = 0, gs;
if (bs <= 10000) {
hra = 0.20 * bs;
da = 0.80 * bs;
} else if (bs <= 20000) {
hra = 0.25 * bs;
da = 0.90 * bs;
} else if (bs <= 30000) {
hra = 0.30 * bs;
da = 0.95 * bs;
} else {
System.out.println("This program supports basic salary up to ₹30000 only.");
scanner.close();
return;
gs = bs + hra + da;
System.out.println("Gross Salary: " + gs);
scanner.close();
2b.menudriven
import java.util.Scanner;
public class MenuDrivenProgram {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int choice, num;
do {
System.out.println("\n----- MENU -----");
System.out.println("1. Factorial");
System.out.println("2. Prime or Not");
System.out.println("3. Even or Odd");
System.out.println("4. Exit");
System.out.print("Enter your choice (1-4): ");
choice = sc.nextInt();
switch (choice) {
case 1:
System.out.print("Enter a number: ");
num = sc.nextInt();
long fact = 1;
for (int i = 1; i <= num; i++) {
fact *= i;
System.out.println("Factorial of " + num + " is " + fact);
break;
case 2:
System.out.print("Enter a number: ");
num = sc.nextInt();
boolean isPrime = true;
if (num <= 1) {
isPrime = false;
} else {
for (int i = 2; i <= Math.sqrt(num); i++) {
if (num % i == 0) {
isPrime = false;
break;
if (isPrime)
System.out.println(num + " is a Prime Number.");
else
System.out.println(num + " is Not a Prime Number.");
break;
case 3:
System.out.print("Enter a number: ");
num = sc.nextInt();
if (num % 2 == 0)
System.out.println(num + " is Even.");
else
System.out.println(num + " is Odd.");
break;
case 4:
System.out.println("Exiting the program. Goodbye!");
break;
default:
System.out.println("Invalid choice! Please enter 1 to 4.");
} while (choice != 4);
sc.close();
}
}
2c.pattern
public class PyramidNumberPattern {
public static void main(String[] args) {
int rows = 5;
for (int i = 1; i <= rows; i++) {
for (int space = 1; space <= rows - i; space++) {
System.out.print(" ");
for (int j = i; j >= 1; j--) {
System.out.print(j);
for (int j = 2; j <= i; j++) {
System.out.print(j);
System.out.println();
3a.no. of 2s
import java.util.Scanner;
public class DigitCounter {
public static int countTwos(int num) {
int count = 0;
while (num > 0) {
if (num % 10 == 2) {
count++;
num /= 10;
return count;
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a non-negative integer: ");
int number = scanner.nextInt();
if (number < 0) {
System.out.println("Invalid input. Please enter a non-negative integer.");
} else {
System.out.println("The number is: " + number);
int twosCount = countTwos(number);
System.out.println("Number of 2s: " + twosCount);
scanner.close();
3b.fibonacci
public class FibonacciSeries {
public static void main(String[] args) {
int n = 10;
int a = 0, b = 1;
System.out.println("First " + n + " numbers of the Fibonacci series:");
for (int i = 1; i <= n; i++) {
System.out.print(a + " ");
int next = a + b;
a = b;
b = next;
4a.parameter books
class Book {
String title;
String author;
double price;
Book() {
title = "Unknown Title";
author = "Unknown Author";
price = 0.0;
System.out.println("Default Constructor:");
printDetails();
Book(String title, String author) {
this.title = title;
this.author = author;
this.price = 0.0; // Default price
System.out.println("\nConstructor with 2 parameters (title, author):");
printDetails();
Book(String title, String author, double price) {
this.title = title;
this.author = author;
this.price = price;
System.out.println("\nConstructor with 3 parameters (title, author, price):");
printDetails();
void printDetails() {
System.out.println("Title: " + title);
System.out.println("Author: " + author);
System.out.println("Price: ₹" + price);
public class BookTest {
public static void main(String[] args) {
Book b1 = new Book(); // default
Book b2 = new Book("Wings of Fire", "Dr. A.P.J. Abdul Kalam"); // 2 parameters
Book b3 = new Book("Clean Code", "Robert C. Martin", 599.99); // 3 parameters
4b.parameter accounts
class Accounts {
String accNo;
double balance;
Accounts(String accNo, double balance) {
boolean isValid = true;
if (accNo == null || accNo.trim().isEmpty()) {
System.out.println("Error: Account number must not be null or empty.");
isValid = false;
if (balance < 0) {
System.out.println("Error: Balance cannot be negative.");
isValid = false;
if (isValid) {
this.accNo = accNo;
this.balance = balance;
System.out.println("\nAccount created successfully:");
printDetails();
} else {
System.out.println("Account creation failed due to invalid data.");
void printDetails() {
System.out.println("Account Number: " + accNo);
System.out.println("Balance: ₹" + balance);
public class AccountTest {
public static void main(String[] args) {
Accounts acc1 = new Accounts("A123456", 5000.00);
Accounts acc2 = new Accounts("", 2000.00);
Accounts acc3 = new Accounts("B7891011", -100.00);
Accounts acc4 = new Accounts(null, -50.00);
5a.sport extend
class Sports {
void play() {
System.out.println("Playing some sport...");
class Football extends Sports {
void play() {
System.out.println("Playing Football on the field.");
class Basketball extends Sports {
void play() {
System.out.println("Dribbling and shooting in Basketball.");
class Rugby extends Sports {
void play() {
System.out.println("Tackling hard in Rugby.");
}
}
public class SportsTest {
public static void main(String[] args) {
Sports s1 = new Football();
Sports s2 = new Basketball();
Sports s3 = new Rugby();
s1.play();
s2.play();
s3.play();
5b.book details
class Publisher {
String name;
Publisher(String name) {
this.name = name;
void display() {
System.out.println("Publisher: " + name);
class Book extends Publisher {
String title;
double price;
Book(String name, String title, double price) {
super(name);
this.title = title;
this.price = price;
void display() {
System.out.println("Book Title: " + title);
System.out.println("Price: ₹" + price);
System.out.println("Publisher: " + name);
public class BookTestjava {
public static void main(String[] args) {
Book b = new Book("Penguin Books", "The Alchemist", 399.00);
b.display();
6.calculate interest
interface Transaction {
void deposit(double amount);
void withdraw(double amount);
class SavingsAccount implements Transaction {
double balance;
SavingsAccount(double balance) {
this.balance = balance;
}
public void deposit(double amount) {
balance += amount;
System.out.println("Deposited ₹" + amount + " in Savings Account.");
public void withdraw(double amount) {
if (amount <= balance) {
balance -= amount;
System.out.println("Withdrew ₹" + amount + " from Savings Account.");
} else {
System.out.println("Insufficient balance in Savings Account.");
void displayBalance() {
System.out.println("Savings Account Balance: ₹" + balance);
class CurrentAccount implements Transaction {
double balance;
CurrentAccount(double balance) {
this.balance = balance;
public void deposit(double amount) {
balance += amount;
System.out.println("Deposited ₹" + amount + " in Current Account.");
}
public void withdraw(double amount) {
if ((balance - amount) >= 2000) {
balance -= amount;
System.out.println("Withdrew ₹" + amount + " from Current Account.");
} else {
System.out.println("Minimum balance of ₹2000 must be maintained in Current
Account.");
void displayBalance() {
System.out.println("Current Account Balance: ₹" + balance);
class RateOfInterest {
void calculateInterest(double balance, double rate, int years) {
double interest = (balance * rate * years) / 100;
System.out.println("Interest for ₹" + balance + " at " + rate + "% for " + years + " years is ₹" +
interest);
public class BankTest {
public static void main(String[] args) {
SavingsAccount sa = new SavingsAccount(5000);
sa.deposit(1000);
sa.withdraw(2000);
sa.displayBalance();
CurrentAccount ca = new CurrentAccount(6000);
ca.deposit(1500);
ca.withdraw(5000);
ca.displayBalance();
RateOfInterest roi = new RateOfInterest();
roi.calculateInterest(sa.balance, 4.0, 2);
roi.calculateInterest(ca.balance, 3.5, 2);
7.zipcode
import java.util.*;
class CityNotFoundException extends Exception {
CityNotFoundException(String message) {
super(message);
class City {
HashMap<Integer, String> cityMap;
City() {
cityMap = new HashMap<>();
cityMap.put(110001, "Delhi");
cityMap.put(400001, "Mumbai");
cityMap.put(560001, "Bangalore");
cityMap.put(700001, "Kolkata");
cityMap.put(600001, "Chennai");
}
void findCityByZipCode(int zip) throws CityNotFoundException {
if (cityMap.containsKey(zip)) {
System.out.println("City for ZIP " + zip + ": " + cityMap.get(zip));
} else {
throw new CityNotFoundException("City not found for ZIP: " + zip);
public class CityTest {
public static void main(String[] args) {
City city = new City();
try {
city.findCityByZipCode(560001);
city.findCityByZipCode(123456);
} catch (CityNotFoundException e) {
System.out.println(e.getMessage());
8.password
import java.util.Scanner;
public class PasswordValidator {
static boolean isValidPassword(String password) {
if (password.length() < 8)
return false;
int digitCount = 0;
for (char ch : password.toCharArray()) {
if (Character.isDigit(ch))
digitCount++;
if (digitCount < 2 || digitCount > 4)
return false;
return true;
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter password: ");
String password = sc.nextLine();
if (isValidPassword(password)) {
System.out.println("Password valid: " + password);
} else {
System.out.println("Password invalid.");
9.linkedlist
import java.util.LinkedList;
public class LinkedListDemo {
public static void main(String[] args) {
LinkedList<String> cities = new LinkedList<>();
cities.add("Delhi");
cities.add("Mumbai");
cities.add("Chennai");
cities.add("Kolkata");
System.out.println("Original List: " + cities);
String firstCity = cities.get(0);
System.out.println("First City: " + firstCity);
cities.set(1, "Bangalore");
System.out.println("After Update: " + cities);
cities.remove("Chennai");
System.out.println("After Removal: " + cities);
10.copy content
import java.io.*;
public class FileCopy {
public static void main(String[] args) {
try {
FileInputStream in = new FileInputStream("source.txt");
FileOutputStream out = new FileOutputStream("destination.txt");
int byteData;
while ((byteData = in.read()) != -1) {
out.write(byteData);
}
in.close();
out.close();
System.out.println("File copied successfully.");
} catch (IOException e) {
System.out.println("Error: " + e.getMessage());
