So this is the Hypothetical program that allows a person to the travel to the year that he want to go in past.

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
import java.nio.charset.StandardCharsets;

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

public class TimeTraveler {
    public static void main(String[] args) {
        // Create a Scanner object to read input from the console
        Scanner scanner = new Scanner(System.in);
        
        // Prompt the user to enter the desired year
        System.out.println("Welcome, Time Traveler! Please enter the year you want to travel to:");
        int desiredYear = scanner.nextInt();
      
        // Create an instance of the TimeMachine class
        TimeMachine timeMachine = new TimeMachine();
        
        // Retrieve the event for the specified year
        String event = timeMachine.getEventForDate(desiredYear);

        // Check if the event is not empty
        if (!event.isEmpty()) {
            // Print a message indicating the year the user has arrived in
            System.out.println("You've arrived in the year " + desiredYear + ".");
            // Print a message indicating the significant event for the specified year
            System.out.println("Here's a significant event that happened in " + desiredYear + ":");
            // Print the retrieved event
            System.out.println(event);
            
            // Write the event to a file
            writeToFile(event, "event_" + desiredYear + ".txt");
            // Print a message indicating that the event details have been written to the file
            System.out.println("Event details written to file.");
        } else {
            // If no event is found for the specified year, print a message indicating so
            System.out.println("Sorry, no significant event found for the year " + desiredYear + ".");
        }
    }
    
    // Method to write the content to a file
    private static void writeToFile(String content, String filename) {
        try (BufferedWriter writer = new BufferedWriter(new FileWriter(filename, StandardCharsets.UTF_8))) {
            writer.write(content);
        } catch (IOException e) {
            // If an IOException occurs during file writing, print the stack trace
            e.printStackTrace();
        }
    }
}

// Class for fetching event details for a given year
class TimeMachine {
    public String getEventForDate(int year) {
        // Construct the URL for the Wikipedia page for the specified year
        String url = "https://en.wikipedia.org/wiki/"+ year +"_in_India";
        StringBuilder event = new StringBuilder();

        try {
            // Connect to the Wikipedia page and retrieve its HTML document
            Document doc = Jsoup.connect(url).get();
            // Select the body element of the HTML document
            Elements paragraphs = doc.select("body");
            // Iterate over paragraphs in the body element
            for (Element paragraph : paragraphs) {
                // Consider the first non-empty paragraph as the event
                String text = paragraph.text().trim();
                if (!text.isEmpty()) {
                    event.append(text).append("\n\n");
                    break;
                }
            }
        } catch (IOException e) {
            // If an IOException occurs during web scraping, print the stack trace
            e.printStackTrace();
        }

        // Return the retrieved event as a string
        return event.toString().trim();
    }
}

output:

1. TimeTraveler: This class contains the main method, which serves as the entry point of the program. It prompts the user to enter a desired year, retrieves the significant event for that year using the TimeMachine class, prints the event to the console, and writes it to a file.
2. TimeMachine: This class is responsible for fetching the significant event for a given year from the Wikipedia page. It utilizes Jsoup for web scraping to retrieve the HTML content of the Wikipedia page, selects the relevant text, and returns it as a string.

The writeToFile method in the TimeTraveler class is used to write the event details to a file with the specified filename. It utilizes a BufferedWriter to write the content to the file with UTF-8 encoding. If an IOException occurs during file writing, the stack trace is printed to the console.