НП Календар на настани

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Comparator;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;

public class EventCalendarTest {
    public static void main(String[] args) throws ParseException {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        scanner.nextLine();
        int year = scanner.nextInt();
        scanner.nextLine();
        EventCalendar eventCalendar = new EventCalendar(year);
        DateFormat df = new SimpleDateFormat("dd.MM.yyyy HH:mm");
        for (int i = 0; i < n; ++i) {
            String line = scanner.nextLine();
            String[] parts = line.split(";");
            String name = parts[0];
            String location = parts[1];
            Date date = df.parse(parts[2]);
            try {
                eventCalendar.addEvent(name, location, date);
            } catch (WrongDateException e) {
                System.out.println(e.getMessage());
            }
        }
        Date date = df.parse(scanner.nextLine());
        eventCalendar.listEvents(date);
        eventCalendar.listByMonth();
    }
}

// vashiot kod ovde

class Event implements Comparable<Event>{
    String name;
    String location;
    Date date;
    public Event(String name, String location, Date date) {
        super();
        this.name = name;
        this.location = location;
        this.date = date;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getLocation() {
        return location;
    }
    public void setLocation(String location) {
        this.location = location;
    }
    public Date getDate() {
        return date;
    }
    public void setDate(Date date) {
        this.date = date;
    }
    @Override
    public String toString() {
        DateFormat df = new SimpleDateFormat("dd MMM, YYY HH:mm");
        String dateFormatted = df.format(date);
        return String.format("%s at %s, %s", dateFormatted,location,name);
    }
    @Override
    public int compareTo(Event o) {
        return Comparator.comparing(Event::getDate)
                .thenComparing(Event::getName).compare(this, o);
    }

}

class EventCalendar{
    Map<String,TreeSet<Event>> map;
    Map<Integer,Integer> mesecno;
    int year;

    public EventCalendar(int year) {
        super();
        this.year = year;
        map=new HashMap<>();
        mesecno=new HashMap<>();
    }

    public void addEvent(String name, String location, Date date)  throws WrongDateException{
        if(date.getYear()!=year-1900) {
            throw new WrongDateException(date);
        }

        int mesec=date.getMonth();

        mesecno.computeIfPresent(mesec, (key,value) -> ++value);

        mesecno.computeIfAbsent(mesec, (key)->{
            return 1;
        });

        String data=date.getMonth()+" "+date.getDate();

        map.computeIfPresent(data, (key,value)->{
            value.add(new Event(name,location,date));
            return value;
        });

        map.computeIfAbsent(data, (key)->{
            TreeSet<Event> set=new TreeSet<>();
            set.add(new Event(name,location,date));
            return set;
        });


    }

    public void listEvents(Date date) {
        String data=date.getMonth()+" "+date.getDate();
        if(map.get(data)==null) {
            System.out.println("No events on this day!");
            return;
        }


        map.get(data).stream().forEach(System.out::println);
    }


    public void listByMonth() {
        for(int i=0;i<12;i++) {
            if(mesecno.get(i)!=null) {
            System.out.printf("%d : %d\n", i+1,mesecno.get(i));
            }else {
                System.out.printf("%d : %d\n", i+1,0);
            }
        }


    }



}

class WrongDateException extends Exception{
    public WrongDateException(Date date) {
        super(String.format("Wrong date: %s", date.toString().replaceAll("GMT", "UTC")));
    }
}