OOP_IO-2x_2023-mirror/lab4

import java.util.Arrays;
import java.util.Comparator;
import java.util.Scanner;

public class Lab4 {

    public static class Student {
        private int grBook;
        private String name;
        private int age;
        private double gpa;
        private String faculty;

        public Student(int grBook, String name, int age, double gpa, String faculty) {
            this.grBook = grBook;
            this.name = name;
            this.age = age;
            this.gpa = gpa;
            this.faculty = faculty;
        }

        public int getGrBook() {
            return grBook;
        }

        public String getName() {
            return name;
        }

        public int getAge() {
            return age;
        }

        public double getGpa() {
            return gpa;
        }

        public String getFaculty() {
            return faculty;
        }
    }

    public static void main(String[] args) {

        int C11 = 2430 % 11;
        System.out.println("\n  ----------------------------------------------------------------------------------------------------------");
        System.out.println("          C17 = " + C11 + ", So, the task is:  Define the student class, which consists of at least 5 fields.");
        System.out.println("  ----------------------------------------------------------------------------------------------------------");

        Student[] students = {
                new Student(1010, "Вікторія", 21, 84.6, "ФІОТ"),
                new Student(2010, "Дарія", 20, 79.8, "РТФ"),
                new Student(3010, "Анатолій", 19, 94.3, "ХТФ"),
                new Student(4040, "Генадій", 22, 62.0, "ІХФ"),
                new Student(5050, "Борис", 18, 89.1, "ФММ")
        };

        Scanner scanner = new Scanner(System.in);
        boolean quit = false;
        while (!quit) {

            System.out.print("\nEnter the field to sort by (greed book, name, age, gpa, faculty) or enter 'quit' to exit: ");
            String input = scanner.nextLine();

            if (!input.equals("greed book") && !input.equals("name") && !input.equals("age") && !input.equals("gpa") && !input.equals("faculty") && !input.equals("quit")) {
                System.out.println("Invalid field to sort by! Please enter 'grBook', 'name', 'age', 'gpa', or 'faculty'.");
                continue;
            }
            if (input.equals("quit")) {
                quit = true;
                System.out.println("Thank you for using my program:)");
                continue;
            }

            String field = input;
            System.out.print("Enter the sort order (asc or desc): ");
            String order = scanner.nextLine();

            if (!order.equals("asc") && !order.equals("desc")) {
                System.out.println("Invalid sort order! Please enter 'asc' or 'desc'.");
                continue;
            }
            
            Comparator<Student> comparator = null;
            switch (field) {
                case "greed book":
                    comparator = Comparator.comparingInt(Student::getGrBook);
                    break;
                case "name":
                    comparator = Comparator.comparing(Student::getName);
                    break;
                case "age":
                    comparator = Comparator.comparingInt(Student::getAge);
                    break;
                case "gpa":
                    comparator = Comparator.comparingDouble(Student::getGpa);
                    break;
                case "faculty":
                    comparator = Comparator.comparing(Student::getFaculty);
                    break;
            }
            if (order.equals("desc")) {
                comparator = comparator.reversed();
            }
            Arrays.sort(students, comparator);
            
            System.out.println("\nSorted by " + field + " (in " + order + "ending order):");
            System.out.println(String.format("%n%-15s | %-20s | %-4s | %-4s | %-10s", "Greed book", "Name", "Age", "GPA", " Faculty"));
            System.out.println("----------------------------------------------------------------");
            for (Student student : students) {
                System.out.println(String.format("%-15d | %-20s | %-4d | %-3.1f | %-10s", student.getGrBook(), student.getName(), student.getAge(), student.getGpa(), student.getFaculty()));
            }
        }
    }
}