Не пропускает валидатор по второму пункту.

package com.javarush.task.task20.task2002;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

/*
Читаем и пишем в файл: JavaRush
*/
public class Solution {
    public static void main(String[] args) {
        //you can find your_file_name.tmp in your TMP directory or adjust outputStream/inputStream according to your file's actual location
        //вы можете найти your_file_name.tmp в папке TMP или исправьте outputStream/inputStream в соответствии с путем к вашему реальному файлу

        try {
            File yourFile = File.createTempFile("your_file_name", null);
            OutputStream outputStream = new FileOutputStream("/Users/NG/Yandex.Disk.localized/Курс javarush/JavaRushTasks/2.JavaCore/src/com/javarush/task/task20/task2002/test1");
            InputStream inputStream = new FileInputStream("/Users/NG/Yandex.Disk.localized/Курс javarush/JavaRushTasks/2.JavaCore/src/com/javarush/task/task20/task2002/test2");

            JavaRush javaRush = new JavaRush();
            //initialize users field for the javaRush object here - инициализируйте поле users для объекта javaRush тут
            User userPiotr = new User();
            userPiotr.setFirstName("Петр");
            userPiotr.setLastName("Иванов");
            SimpleDateFormat sdf = new SimpleDateFormat("dd MM yyyy");
            userPiotr.setBirthDate(sdf.parse("02 11 1988"));
            userPiotr.setMale(true);
            userPiotr.setCountry(User.Country.UKRAINE);

            User userVictor = new User();
            userVictor.setFirstName("Виктор");
            userVictor.setLastName("Иванов");
            userVictor.setBirthDate(sdf.parse("02 11 1988"));
            userVictor.setMale(true);
            userVictor.setCountry(User.Country.UKRAINE);

            User userNull = new User();

            // List<User> users = new ArrayList<>();
            javaRush.users.add(userPiotr);
            javaRush.users.add(userVictor);
            javaRush.users.add(userNull);


            javaRush.save(outputStream);
            outputStream.flush();

            JavaRush loadedObject = new JavaRush();
            loadedObject.load(inputStream);
            boolean check = loadedObject.equals(javaRush);
            //here check that the codeGym object is equal to the loadedObject object - проверьте тут, что javaRush и loadedObject равны

            outputStream.close();
            inputStream.close();

        } catch (IOException e) {
            //e.printStackTrace();
            System.out.println("Oops, something is wrong with my file");
        } catch (Exception e) {
            //e.printStackTrace();
            System.out.println("Oops, something is wrong with the save/load method");
        }


    }

    public static class JavaRush {
        public List<User> users = new ArrayList<>();

        public void save(OutputStream outputStream) throws Exception {
            PrintWriter out = new PrintWriter(outputStream);
            if (users.size() > 0) {
                for (User user : users) {
                    out.println(user.getFirstName() == null ? "null" : user.getFirstName());
                    out.println(user.getLastName() == null ? "null" : user.getLastName());
                    out.println(user.getBirthDate() == null ? "null" : new SimpleDateFormat("dd MM yyyy", Locale.ENGLISH).format(user.getBirthDate()));
                    out.println(user.isMale());
                    out.println(user.getCountry() == null ? "null" : user.getCountry());
                    out.flush();
                }

            }
            else {
                out.println(-1);
                out.flush();
            }
            out.close();
        }

        public void load(InputStream inputStream) throws Exception {
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
            while (reader.ready())
            {
                int x = Integer.parseInt(reader.readLine());
                if (x > 0) {
                    for (int i = 0; i < x; i++) {
                        User user1 = new User();
                        String s = reader.readLine();
                        user1.setFirstName((s == "null" ? null : s));
                        s = reader.readLine();
                        user1.setLastName((s == "null" ? null : s));
                        s = reader.readLine();
                        user1.setBirthDate(s == "null" ? null : new SimpleDateFormat("dd MM yyyy", Locale.ENGLISH).parse(s));
                        user1.setMale(Boolean.valueOf(reader.readLine()));
                        s = reader.readLine();
                        user1.setCountry(s == "null" ? null : (User.Country.valueOf(reader.readLine())));
                        this.users.add(user1);
                    }

                }
                else {users = new ArrayList<>();}

            }
            reader.close();
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;

            JavaRush javaRush = (JavaRush) o;

            return users != null ? users.equals(javaRush.users) : javaRush.users == null;

        }

        @Override
        public int hashCode() {
            return users != null ? users.hashCode() : 0;
        }
    }
}