Q1 Java Program to Read The Number From Standard Input
Ans1-> public class ReadNumberExample1
{
public static void main(String[] args)
{
//object of the Scanner class
Scanner sc=new Scanner(System.in);
System.out.print("Enter a number: ");
//invoking nextInt() method that reads an integer input by keyboard
//storing the input number in a variable num
int num = sc.nextInt();
//closing the Scanner after use
sc.close();
//prints the number
System.out.println("The number entered by the user is: "+num);
}
}
Q2 Write a program that print your name on the screen.
Ans2->
public class PrintName {
public static void main(String[] args)
{
String name = "Your Name";
System.out.println("Hello, " + name + "!");
}
}
Q3 Write a program that fine the size of int, float, double and char.
Ans-> import java.util.*;
/* how to find size of variable in java */
class SizeofdataTypes
{
public static void main(String[] args) {
System.out.println("Size of int: " + (Integer.SIZE / 8) + " bytes.");
System.out.println("Size of long: " + (Long.SIZE / 8) + " bytes.");
System.out.println("Size of char: " + (Character.SIZE / 8) + " bytes.");
System.out.println("Size of float: " + (Float.SIZE / 8) + " bytes.");
System.out.println("Size of double: " + (Double.SIZE / 8) + " bytes.");
}
}
Q4 Write a program that check whether character is vowel or consonant.
Ans-> import java.io.*;
class Prep {
static void Vowel_Or_Consonant(char y)
{
if (y == 'a' || y == 'e' || y == 'i' || y == 'o'
|| y == 'u' || y == 'A' || y == 'E' || y == 'I'
|| y == 'O' || y == 'U')
System.out.println("It is a Vowel.");
else
System.out.println("It is a Consonant.");
}
static public void main(String[] args)
{
Vowel_Or_Consonant('W');
Vowel_Or_Consonant('I');
}
}
Q5 Write a program that find the larger number among three number.
Ans-> import java.io.*;
class PrepBytes {
// Function to find the biggest of three numbers
static int biggestOfThree(int x, int y, int z)
{
return z > (x > y ? x : y) ? z : ((x > y) ? x : y);
}
// Main driver function
public static void main(String[] args)
{
// Declaring variables for 3 numbers
int a, b, c;
// Variable holding the largest number
int largest;
a = 5;
b = 10;
c = 3;
// Calling the above function in main
largest = biggestOfThree(a, b, c);
// Printing the largest number
System.out.println(largest
+ " is the largest number.");
}
}
Q6 Write a program that fine the ASCII value of Character.
Ans-> public class AsciiValue
{
public static void main(String[] args)
{
char ch = 'a';
int ascii = ch;
// You can also cast char to int
int castAscii = (int) ch;
System.out.println("The ASCII value of " + ch + " is: " + ascii);
System.out.println("The ASCII value of " + ch + " is: " + castAscii);
}
}
Q7 Write a program that check Whether a number is palindrome or not.
Ans-> import java.util.Scanner;
public class Palindrome
{
public static void main(String args[])
{
int n, m, rev = 0, x;
Scanner s = new Scanner(System.in);
System.out.print("Enter the number:");
n = s.nextInt();
m = n;
while(n > 0)
{
x = n % 10;
rev = rev * 10 + x;
n = n / 10;
}
if(rev == m)
{
System.out.println(" "+m+" is a palindrome number");
}
else
{
System.out.println(" "+m+" is not a palindrome number");
}
}
}
Q8 Write a program that display the factor of a number.
Ans-> public class Main
{
public static void main(String[] args) {
int num = 10;
System.out.println( "Factors of " + num + " are " );
// finding and printing factors b/w 1 to num
for(int i = 1; i <= num; i++)
{
if(num % i == 0)
System.out.println(i + " ");
}
}
}
// Time Complexity : O(n)
// Auxiliary Space : O(1)
Q9 Write a program that create star pyramid on the screen.
Ans-> import java.io.*;
// Java code to demonstrate star patterns
public class GeeksForGeeks
{
// Function to demonstrate printing pattern
public static void printStars(int n)
int i, j;
// outer loop to handle number of rows
// n in this case
for(i=0; i<n; i++)
{
// inner loop to handle number of columns
// values changing acc. to outer loop
for(j=0; j<=i; j++)
// printing stars
System.out.print("* ");
// ending line after each row
System.out.println();
// Driver Function
public static void main(String args[])
int n = 5;
printStars(n);
}
}
Q10 Write a program that fine the area of rectangle and triangle by using the two different
function.
Ans-> class Rectangle implements Area
{
public double Compute(double l, double b)
{
return (l*b);
}
}
class Triangle implements Area
{
public double Compute(double b, double h)
{
return (b*h/2);
}
}
public class MainArea
{
public static void main(String args[])
{
Rectangle rect = new Rectangle();
double RArea = rect.Compute(10, 20);
System.out.println("The area of the Rectangle is "+RArea);
Triangle tri = new Triangle();
double TArea = tri.Compute(10, 20);
System.out.println("The area of the triangle is "+TArea);
}
}
Q11 Write a program that make a calculator by using the function.
Ans-> import java.util.Scanner;
public class SimpleCalculator {
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.print("Enter the first number: ");
int firstNumber = sc.nextInt();
System.out.print("Enter the second number: ");
int secondNumber = sc.nextInt();
System.out.print("Enter the type of operation you want to perform (+, -, *, /, %): ");
String operation = sc.next();
int result = performOperation(firstNumber, secondNumber, operation);
System.out.println("Your answer is: " + result);
}
public static int performOperation(int firstNumber, int secondNumber, String operation)
{
int result = 0;
if (operation.equals("+")) {
result = firstNumber + secondNumber;
}
else if (operation.equals("-")) {
result = firstNumber - secondNumber;
}
else if (operation.equals("*")) {
result = firstNumber * secondNumber;
}
else if (operation.equals("%")) {
result = firstNumber % secondNumber;
}
else if (operation.equals("/")) {
result = firstNumber / secondNumber;
}
else {
System.out.println("Invalid operation");
}
return result;
}
}
Q12 Write a program that create the class and object.
Ans-> / Java Program for class example
class Student {
// data member (also instance variable)
int id;
// data member (also instance variable)
String name;
public static void main(String args[])
// creating an object of
// Student
Student s1 = new Student();
System.out.println(s1.id);
System.out.println(s1.name);
}
}
Q13 Write a program that take the student detail and display on the screen by the help of class.
Ans-> //program to get student details
import java.util.Scanner;
public class GetStudentDetails
{
public static void main(String args[])
{
String name;
int roll, math, phy, eng;
Scanner SC=new Scanner(System.in);
System.out.print("Enter Name: ");
name=SC.nextLine();
System.out.print("Enter Roll Number: ");
roll=SC.nextInt();
System.out.print("Enter marks in Maths, Physics and English: ");
math=SC.nextInt();
phy=SC.nextInt();
eng=SC.nextInt();
int total=math+eng+phy;
float perc=(float)total/300*100;
System.out.println("Roll Number:" + roll +"\tName: "+name);
System.out.println("Marks (Maths, Physics, English): " +math+","+phy+","+eng);
System.out.println("Total: "+total +"\tPercentage: "+perc);
}
Q14 Write a program that show the working of Multilevl inheritance.
Ans->class Animal {
// field and method of the parent class
String name;
public void eat() {
System.out.println("I can eat");
}
}
// inherit from Animal
class Dog extends Animal {
// new method in subclass
public void display() {
System.out.println("My name is " + name);
}
}
class Main {
public static void main(String[] args) {
// create an object of the subclass
Dog labrador = new Dog();
// access field of superclass
labrador.name = "Rohu";
labrador.display();
// call method of superclass
// using object of subclass
labrador.eat();
}
}
Q15 Write a program that create the package.
Ans-> package p2;
import java.util.*;
public class Sub
{
int d;
public void diff()
{
System.out.print("Enter the first number: ");
Scanner scan=new Scanner(System.in);
int x=scan.nextInt();
System.out.print("Enter the second number: ");
Scanner scan1=new Scanner(System.in);
int y=scan1.nextInt();
d=x-y;
System.out.println("Difference="+d);
}
}
Q16 Write a program that show the working of JDBC.
Ans-> import java.io.*;
import java.sql.*;
class GFG {
public static void main(String[] args) throws Exception
String url
= "jdbc:mysql://localhost:3306/table_name"; // table details
String username = "rootgfg"; // MySQL credentials
String password = "gfg123";
String query
= "select *from students"; // query to be run
Class.forName(
"com.mysql.cj.jdbc.Driver"); // Driver name
Connection con = DriverManager.getConnection(
url, username, password);
System.out.println(
"Connection Established successfully");
Statement st = con.createStatement();
ResultSet rs
= st.executeQuery(query); // Execute query
rs.next();
String name
= rs.getString("name"); // Retrieve name from db
System.out.println(name); // Print result on console
st.close(); // close statement
con.close(); // close connection
System.out.println("Connection Closed....");
}
}
Q17 Write a program that function over loading. Create minimum same name 4 function.
Ans-> // Java program to demonstrate working of method
// overloading in Java
public class Sum {
// Overloaded sum(). This sum takes two int parameters
public int sum(int x, int y) { return (x + y); }
// Overloaded sum(). This sum takes three int parameters
public int sum(int x, int y, int z)
return (x + y + z);
// Overloaded sum(). This sum takes two double
// parameters
public double sum(double x, double y)
return (x + y);
// Driver code
public static void main(String args[])
Sum s = new Sum();
System.out.println(s.sum(10, 20));
System.out.println(s.sum(10, 20, 30));
System.out.println(s.sum(10.5, 20.5));
}
}
Q18 Write a program that show the working of function hiding.
Ans->// Java program to demonstrate
// method Hiding in java
// Base Class
class Complex {
public static void f1()
System.out.println(
"f1 method of the Complex class is executed.");
}
}
// class child extend Demo class
class Sample extends Complex {
public static void f1()
System.out.println(
"f1 of the Sample class is executed.");
}
}
public class Main {
public static void main(String args[])
Complex d1 = new Complex();
// d2 is reference variable of class Demo that
// points to object of class Sample
Complex d2 = new Sample();
// But here method will be call using type of
// reference
d1.f1();
d2.f1();
}
}
Q19 Write a program for Interface.
Ans-> interface printable{
void print();
}
class A6 implements printable{
public void print(){System.out.println("Hello");}
public static void main(String args[]){
A6 obj = new A6();
obj.print();
}
}
Q20 Write a program show the working of abstract class.
Ans->
// Java Program to implement Abstract Class
// having constructor, data member, and methods
import java.io.*;
abstract class Subject {
Subject() {
System.out.println("Learning Subject");
abstract void syllabus();
void Learn(){
System.out.println("Preparing Right Now!");
}
}
class IT extends Subject {
void syllabus(){
System.out.println("C , Java , C++");
}
}
class GFG {
public static void main(String[] args) {
Subject x=new IT();
x.syllabus();
x.Learn();
}
}
Q21 Write a program show the working of constructor and destructor.
Ans-> public class DestructorExample
{
public static void main(String[] args)
{
DestructorExample de = new DestructorExample ();
de.finalize();
de = null;
System.gc();
System.out.println("Inside the main() method");
}
protected void finalize()
{
System.out.println("Object is destroyed by the Garbage Collector");
}
}
