How to install JDK or How to start Java.

Please follow the below link-

https://www.youtube.com/watch?v=3u1fu6f8Hto

Reverse a number or check number is palindrome or not

import java.util.Scanner;

public class ReverseNumber {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.println("Enter a number which you want to reverse: ");
        int a = in.nextInt(), r=0, s=0, p=a;
       
        while(p!=0){
            r = p%10;
            p = p/10;
            s = s*10 + r;
        }
        if(s==a){
            System.out.println("number entered by user "+a+" is a palindrome.");
        }else
            System.out.println("number entered by user "+a+" is not a palindrome.");
    }
}

How to get the dropdown value in notepad ?

Note: FileWriter("path of the directory with filename.txt");

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.interactions.Actions;


public class DropdownNotepad extends Thread {
    public static WebDriver driver;
    public static void main(String[] args) throws IOException {
        driver = new FirefoxDriver();
        driver.get("http://www.etouch.net/home/index.html");
        WebElement service = driver.findElement(By.xpath("//a[text()='Services']"));
        Actions act = new Actions(driver);
        act.moveToElement(service).perform();
        List<WebElement> dropdown = driver.findElements(By.xpath("//li[@id='services']//ul//ul/li"));
        System.out.println(dropdown.size());
       
        FileWriter fileWriter = new FileWriter("C:\\selenium\\out1.txt");
        BufferedWriter bufferedWriter = new BufferedWriter(fileWriter);
       
       
       
        for(WebElement ele: dropdown){
            System.out.println(ele.getText());
            bufferedWriter.write(ele.getText()+"\n");
        }
        bufferedWriter.close();
       
        driver.close();
    }
}

Write a program to check number is Palindrome or not / Write a program to reverse a number.

import java.util.Scanner;

class Palindrome{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        System.out.println("enter a number");
        int n = in.nextInt();
        int a = n;
        int palindrome =0;
        int r = 0;
        while(n>0){
            r = n%10;
            n = n/10;
            palindrome = palindrome*10 + r;
        }
        System.out.println("Reverse of the entered num is: "+palindrome);
        if(palindrome==a){
            System.out.println(a+" number is palindrome.");
        }else{
            System.out.println(a+" number is not palindrome.");
        }
    }
}

How to swap the two numbers without using 3rd variable.

import java.util.Scanner;

public class Swapping{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        System.out.println("enter 1st number a: ");
        int a = in.nextInt();
        System.out.println("enter 2nd number b: ");
        int b = in.nextInt();
       
        System.out.println("before swapping a="+a+" and b= "+b);
        a = a+b;
        b = a-b;
        a = a-b;
        System.out.println("after swapping a="+a+" and b= "+b);
    }
}

How to login, get the number of mails in inbox and logout from the gmail account.

import java.util.List;
import java.util.Scanner;
import java.util.concurrent.TimeUnit;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;

public class InboxCount {

    public static void main(String[] args) {
        Scanner kb = new Scanner(System.in);
        System.out.println("enter ur gmail id: ");
        String id = kb.nextLine();
        System.out.println("enter ur gmail pass: ");
        String password = kb.nextLine();
       
       
        WebDriver driver = new FirefoxDriver();
        driver.manage().timeouts().implicitlyWait(50, TimeUnit.SECONDS);
        driver.get("https://accounts.google.com/ServiceLogin?service=mail&passive=true&rm=false&continue=https%3A%2F%2Fmail.google.com%2Fmail%2F&ss=1&scc=1&ltmpl=default&ltmplcache=2&hl=en&emr=1&elo=1");
        driver.findElement(By.id("Email")).sendKeys(id);
        driver.findElement(By.xpath("//input[@id='Passwd']")).sendKeys(password);
        driver.findElement(By.xpath("//input[@type='checkbox']")).click();
        driver.findElement(By.name("signIn")).click();
       
        String inbox = driver.findElement(By.xpath("//a[@href='https://mail.google.com/mail/u/0/#inbox']")).getText();
        System.out.println(inbox);
       
        //sign out
        driver.findElement(By.xpath("//span[@class='gb_V gbii']")).click();
        driver.findElement(By.linkText("Sign out")).click();
       
        driver.close();
       
    }
}

How to get the suggestion's text by google which come as dropdown while typing in the search box of google.

package BhanuSir;

import java.io.File;
import java.io.IOException;
import java.util.List;
import java.util.Scanner;
import java.util.concurrent.TimeUnit;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.firefox.FirefoxProfile;

public class GoogleSearch {
    public static void main(String[] args) {
        System.out.println("Enter the word which u want to search in Google: ");
        Scanner in = new Scanner(System.in);
        String srchWord = in.nextLine();
        WebDriver driver = new FirefoxDriver();
        driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
        driver.get("https://www.google.co.in/");
       
        driver.findElement(By.name("q")).sendKeys(srchWord);
        //get the test suggested by google from the dropdown.
        List<WebElement> sugg = driver.findElements(By.xpath("//table[@class='gssb_m']/tbody/tr"));
        for(WebElement ele: sugg){
            System.out.println(ele.getText());
        }
        driver.close();
    }
}

How to get the current date and time.

import java.util.*;

class GetCurrentDateAndTime
{
   public static void main(String args[])
   {
      int day, month, year;
      int second, minute, hour;
      GregorianCalendar date = new GregorianCalendar();

      day = date.get(Calendar.DAY_OF_MONTH);
      month = date.get(Calendar.MONTH);
      year = date.get(Calendar.YEAR);

      second = date.get(Calendar.SECOND);
      minute = date.get(Calendar.MINUTE);
      hour = date.get(Calendar.HOUR);
     
      System.out.println("Current date is  "+day+"/"+(month+1)+"/"+year);
      System.out.println("Current time is  "+hour+" : "+minute+" : "+second);
   }
}   

write a program to get the Factorial of a number

import java.util.Scanner;

public class Fac{
    public static void main(String args[]){
        Scanner in = new Scanner(System.in);
        System.out.println("enter the num for which u want the factorial");
        int num = in.nextInt();
        for(int i=num-1; i>0; i-- ){
            num = num*i;
        }
        System.out.println(num);
    }
}

Wrapper Class

coming soon.

Exception Handling

coming soon.

String Class

coming soon.

Object Class

coming soon.

Array Class

coming soon.

Inharitance

coming soon.

Polymorphism

coming soon.

Encapsulation

coming soon.

Interface

coming soon.

Type Casting

coming soon.

Constructor

coming soon.