Main ----- package E5_FootballTeamGenerator;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

        String line;

        Map<String, Team> storeTeams = new HashMap<>();

        while (!"END".equals((line = reader.readLine()))) {
            String[] tokens = line.split(";");
            String cmd = tokens[0];
            String teamName = tokens[1];

            try {

                switch (cmd.toLowerCase()) {
                    case "team":
                        storeTeams.putIfAbsent(teamName, new Team(teamName));


                        break;
                    case "add":
                        if (!storeTeams.containsKey(teamName)) {
                            throw new IllegalArgumentException("Team " + teamName + " does not exist.");
                        }

                        Player player = new Player(tokens[2], Integer.parseInt(tokens[3]), Integer.parseInt(tokens[4]),
                                Integer.parseInt(tokens[5]), Integer.parseInt(tokens[6]), Integer.parseInt(tokens[7]));
                        storeTeams.get(teamName).addPlayer(player);

                        break;
                    case "remove":
                        storeTeams.get(teamName).removePlayer(tokens[2]);
                        break;
                    case "rating":
                        if (!storeTeams.containsKey(teamName)) {
                            throw new IllegalArgumentException("Team " + teamName + " does not exist.");
                        }
                        System.out.println(storeTeams.get(teamName).toString());
                        break;
                }

            } catch (IllegalArgumentException e) {
                System.out.println(e.getMessage());
            }

        }
    }
}
Player ---------

package E5_FootballTeamGenerator;

public class Player {
    private String name;
    private int endurance;
    private int sprint;
    private int dribble;
    private int passing;
    private int shooting;

    public Player(String name, int endurance, int sprint, int dribble, int passing, int shooting) {
        this.setName(name);
        this.setEndurance(endurance);
        this.setSprint(sprint);
        this.setDribble(dribble);
        this.setPassing(passing);
        this.setShooting(shooting);
    }


    public String getName() {
        return this.name;
    }

    private void setName(String name) {
        if (name.trim().isEmpty()) {
            throw new IllegalArgumentException("A name should not be empty.");
        }
        this.name = name;
    }

    private void setEndurance(int endurance) {
       validateStats("Endurance",endurance);
        this.endurance = endurance;
    }

    private void setSprint(int sprint) {
        validateStats( "Sprint",sprint);
        this.sprint = sprint;
    }

    private void setDribble(int dribble) {
        validateStats("Dribble", dribble);
        this.dribble = dribble;
    }

    private void setPassing(int passing) {
        validateStats("Passing", passing);
        this.passing = passing;
    }

    private void setShooting(int shooting) {
        validateStats("Shooting", shooting);
        this.shooting = shooting;
    }

    private void validateStats(String source, int value) {
        if (value < 0 || value > 100) {
            throw new IllegalArgumentException(source + " should be between 0 and 100.");
        }
    }

    public double overallSkillLevel() {
        double sum = this.endurance +
                this.sprint +
                this.dribble +
                this.passing +
                this.shooting;

        return sum / 5;
    }

}

Team --------

package E5_FootballTeamGenerator;

import java.util.ArrayList;
import java.util.List;

public class Team {
    private String name;
    private List<Player> players;

    public Team(String name) {
        this.setName(name);
        this.players = new ArrayList<>();
    }


    public String getName() {
        return this.name;
    }

    private void setName(String name) {
        if (name == null || name.trim().isEmpty()) {
            throw new IllegalArgumentException("A name should not be empty.");
        }
        this.name = name;
    }


    public void addPlayer(Player player) {
        this.players.add(player);
    }

    public void removePlayer(String name) {
        Player player = this.players.stream().filter(e -> e.getName().equals(name)).findFirst().orElse(null);
        if(player != null){
            this.players.remove(player);
        }else{
            throw new IllegalArgumentException("Player "+ name +" is not in Arsenal team.");
        }

    }

    public double getRating() {
        return Math.round(this.players.stream()
                .mapToDouble(Player::overallSkillLevel)
                .average()
                .orElse(0));
    }


    @Override
    public String toString() {
        return String.format("%s - %.0f", this.name, this.getRating());
    }
}