Chat Games Setup

Let's make group chat games! To distinguish each group we use the update.getMessage().getChatId() function since each chat has a unique id. So let's start off with the basics: We need an object to hold data about the progress of the current game, and each chat must have its own object. We will accomplish this with a HashMap which will link each chat ID to a game object:

// to play separate games on separate groups
private static HashMap<Long, Game> games = new HashMap<>();

Create a new file in your src directory named GameHandler.java to keep the bot class clean. We are going to create a static class Game in GameHandler.java which will hold all games being played and their progress:

private static class Game {
    // for upcoming tutorial
    // private ImageGuess guessGame = null;
}

GameHandler will have a static check function that will be called from the KodeCentralBot onUpdateReceived function. Check function:

public static void check(KodeCentralBot kodeCentralBot, Update update) {
    Game current = null;
    long chat_id = update.getMessage().getChatId();
    if (games.containsKey(chat_id))
        current = games.get(chat_id);
    // check what game, etc.. (future)
}

That's all the new code for now.

KodeCentralBot.java

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;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class KodeCentralBot extends TelegramLongPollingBot {
    @Override
    public void onUpdateReceived(Update update) {

        // We check if the update has a message and the message has text
        if (update.hasMessage() && update.getMessage().hasText()) {

            // get the username, id, and the message text
            String username = update.getMessage().getChat().getUserName();
            long user_id = update.getMessage().getChat().getId();
            String message_text = update.getMessage().getText();
            long chat_id = update.getMessage().getChatId();

            SendMessage message = new SendMessage() // Create a message object object
                    .setChatId(chat_id)
                    .setText(message_text);

            // echo bot: the bot response is the same as the incoming update message text
            log(username, Long.toString(user_id), message_text, message_text);

            // NEW:
            GameHandler.check(this, update);
            try {
                execute(message); // Sending our message object to user
            } catch (TelegramApiException e) {
                e.printStackTrace();
            }
        }
    }

    private void log(String username, String chatId, String textReceived, String botResponse) {
        System.out.println("----------------------------\n");
        // print out in PM/AM time
        DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd h:mm a");
        Date date = new Date();
        System.out.println(dateFormat.format(date));
        System.out.println("Message from " + username + ". (id = " + chatId + ") \n Text - " + textReceived);
        System.out.println("Bot answer: \n Text - " + botResponse);
    }

    @Override
    public String getBotUsername() {
        // Return bot username
        // If bot username is @KodeCentralBot, it must return 'KodeCentralBot'
        return "KodeCentralBot";
    }

    @Override
    public String getBotToken() {
        // Return bot token from BotFather
        return "token";
    }
}

GameHandler.java

import org.telegram.telegrambots.meta.api.objects.Update;

import java.util.HashMap;

public class GameHandler {

    private static class Game {

        // for upcoming tutorial
        //private ImageGuess guessGame = null;
    }

    // to play separate games on separate groups
    private static HashMap<Long, Game> games = new HashMap<>();

    public static void check(KodeCentralBot kodeCentralBot, Update update) {
        Game current = null;
        long chat_id = update.getMessage().getChatId();
        if (games.containsKey(chat_id))
            current = games.get(chat_id);

        // check what game, etc.. (future)
    }
}

And that's it for the setup! We will use this code for all future games!