Star Enigma

import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class StarEnigma {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int countMessages = Integer.parseInt(scanner.nextLine());

        String regex = "@(?<planetName>[A-Za-z]+)[^@!:>-]*:(?<population>[0-9]+)[^@!:>-]*!(?<attack>[AD])![^@!:>-]*->(?<soldierCount>[0-9]+)";
        Pattern pattern = Pattern.compile(regex);

        List<String> attackersPlanets = new ArrayList<>();
        List<String> destroyedPlanets = new ArrayList<>();

        for (int messageCount = 1; messageCount <= countMessages; messageCount++) {
            String encryptedMessage = scanner.nextLine();

            String decryptedMessage = getDecryptedMessage(encryptedMessage);
            Matcher matcher = pattern.matcher(decryptedMessage);

            if (matcher.find()) {
                String planetName = matcher.group("planetName");
                //    int planetPopulation = Integer.parseInt(matcher.group("planetPopulation"));
                String attackType = matcher.group("attack");
                //    int soldierCount = Integer.parseInt(matcher.group("soldierCount"));

                if (attackType.equals("A")) {
                    attackersPlanets.add(planetName);
                } else if (attackType.equals("D")) {
                    destroyedPlanets.add(planetName);
                }
            }
        }
        System.out.println("Attacked planets: " + attackersPlanets.size());
        Collections.sort(attackersPlanets);
        attackersPlanets.forEach(planet -> System.out.println("-> " + planet));

        System.out.println("Destroyed planets: " + destroyedPlanets.size());
        Collections.sort(destroyedPlanets);
        destroyedPlanets.forEach(planet -> System.out.println("-> " + planet));
    }

    private static String getDecryptedMessage(String encryptedMessage) {
        int countLetters = getSpecialLetterCounts(encryptedMessage);
        StringBuilder decryptedMessage = new StringBuilder();

        for (char symbol : encryptedMessage.toCharArray()) {
            char newSymbol = (char) (symbol - countLetters);
            decryptedMessage.append(newSymbol);
        }
        return decryptedMessage.toString();
    }

    private static int getSpecialLetterCounts(String encryptedMessage) {
        int counter = 0;
        for (char symbol : encryptedMessage
                .toLowerCase(Locale.ROOT)
                .toCharArray()) {
            if (symbol == 's' || symbol == 'a'
                    || symbol == 't' || symbol == 'r') {
                counter++;
            }
        }
        return counter;
    }
}