Creating a Chat Bot in Java: A Step-by-Step Guide for Beginners

Why Java is an Excellent Choice for Creating a Chat Bot?

When it comes to developing chat bots, many immediately think of Python or Node.js. But Java remains a powerful and reliable tool, especially for corporate projects. Reliability, strong typing, and a huge number of libraries make Java ideal for creating bots that must work 24/7 without failures.

In this guide, we will create a simple but functional chat bot in Java for Telegram step by step. You will learn how to set up a project, handle commands, and send messages. By the end of the article, you will have a working bot that you can launch immediately.

Let's dive into the world of chat bots in Java!

What Do We Need?

Before writing code, make sure you have:

• JDK 11 or higher (recommended 17 or 21)
• IntelliJ IDEA (Community Edition will work) or another IDE
• Maven or Gradle (we will use Maven)
• A Telegram account and a smartphone/computer

Everything else — libraries and settings — we will do along the way. If you are a beginner, don't be scared: creating a chat bot in Java is easier than it seems.

Step 1. Registering the Bot in Telegram

First, you need to get a token — a unique key that will allow your code to communicate with Telegram servers.

1. Open Telegram and find the bot @BotFather.
2. Send the command /newbot.
3. Come up with a name (e.g., JavaTestBot) and a username ending in bot (e.g., JavaTestExampleBot).
4. After creation, BotFather will give you a token. Save it — you will need it in the code.

Done! Now we have the "soul" of the future chat bot in Java.

Step 2. Creating a Maven Project

Open IntelliJ and create a new project:

• File → New → Project
• Select Maven and Java 17
• Set GroupId (e.g., com.example) and ArtifactId (e.g., telegram-bot)

Now open the pom.xml file and add a dependency for working with the Telegram API. We will use the popular library TelegramBots:

<dependencies>    <dependency>        <groupId>org.telegram</groupId>        <artifactId>telegrambots</artifactId>        <version>6.9.7.1</version>    </dependency></dependencies>

Save the file and wait for Maven to download the libraries. This is the foundation for any Java Telegram bot.

Step 3. Writing the Main Bot Class

Create a new Java class named MyTelegramBot. It will extend the TelegramLongPollingBot class. Here is the minimal code:

import org.telegram.telegrambots.bots.TelegramLongPollingBot;import org.telegram.telegrambots.meta.api.methods.send.SendMessage;import org.telegram.telegrambots.meta.api.objects.Update;import org.telegram.telegrambots.meta.exceptions.TelegramApiException;

public class MyTelegramBot extends TelegramLongPollingBot {

    @Override    public String getBotUsername() {        return "JavaTestExampleBot"; // replace with your bot's name    }

    @Override    public String getBotToken() {        return "YOUR_TOKEN_HERE"; // insert the token from BotFather    }

    @Override    public void onUpdateReceived(Update update) {        // Check if there is a message        if (update.hasMessage() && update.getMessage().hasText()) {            String messageText = update.getMessage().getText();            long chatId = update.getMessage().getChatId();

            // Simple response to the /start command            if (messageText.equals("/start