TreeSet after class exercises

TreeSet At the bottom are red and black trees , There is order in storage . Here are two small exercises .

package exercise;

/**
 * @author 
 * @create 2022-04-20-18:08
 */
public class MyDate {
    private int year;
    private int month;
    private int day;

    public MyDate() {
    }

    public MyDate(int year, int month, int day) {
        this.year = year;
        this.month = month;
        this.day = day;
    }

    public int getYear() {
        return year;
    }

    public void setYear(int year) {
        this.year = year;
    }

    public int getMonth() {
        return month;
    }

    public void setMonth(int month) {
        this.month = month;
    }

    public int getDay() {
        return day;
    }

    public void setDay(int day) {
        this.day = day;
    }

    @Override
    public String toString() {
        return "MyDate{" +
                "year=" + year +
                ", month=" + month +
                ", day=" + day +
                '}';
    }
}

package exercise;

/**
 * @author 
 * @create 2022-04-20-18:10
 */
public class Employee implements Comparable{
    private String name;
    private int age;
    private MyDate birthday;

    public Employee() {
    }

    public Employee(String name, int age, MyDate birthday) {
        this.name = name;
        this.age = age;
        this.birthday = birthday;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public MyDate getBirthday() {
        return birthday;
    }

    public void setBirthday(MyDate birthday) {
        this.birthday = birthday;
    }

    @Override
    public String toString() {
        return "Employee{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", birthday=" + birthday +
                '}';
    }

    @Override
    public int compareTo(Object o) {
        if (o instanceof Employee){
            Employee e=(Employee) o;
            return this.name.compareTo(e.name);
        }
//        return 0;
        throw new RuntimeException(" The incoming data types are inconsistent ！");
    }
}

package exercise;

import org.junit.Test;

import java.util.Comparator;
import java.util.Iterator;
import java.util.TreeSet;

/**
 *  Create five objects of this class , And put these objects in TreeSet Collection ,（TreeSet You need to use generics to define ） Set in the following two ways 
 *  The elements in are sorted , And traverse the output ：
 * （1） send Employee Realization comparable Interface , And press name Sort 
 * （2） establish TreeSet Time passes in comparator object , Sort by birthday date 
 *
 * @author 
 * @create 2022-04-20-18:16
 */
public class EmployeeTest {
    // Question two ： By birthday date 
    @Test
    public void test2(){
        TreeSet set =new TreeSet(new Comparator() {
            @Override
            public int compare(Object o1, Object o2) {
                if (o1 instanceof Employee && o2 instanceof Employee ){
                    Employee e1=(Employee) o1;
                    Employee e2=(Employee) o2;
                    MyDate b1 = e1.getBirthday();
                    MyDate b2 = e2.getBirthday();
                    // Comparison year 
                    int minusYear = b1.getYear() - b2.getYear();
                    if (minusYear!=0){
                        return minusYear;
                    }
                    // Comparison month 
                    int minusMonth=b1.getMonth()-b2.getMonth();
                    if (minusMonth!=0){
                        return minusMonth;
                    }
                    // Comparison day 
                    return b1.getDay()-b2.getDay();


                }
//                return 0;
                throw new RuntimeException(" The incoming data type is incorrect ！");
            }
        });
        Employee e1=new Employee("LiuDeHua",55,new MyDate(1965,5,4));
        Employee e2=new Employee("ZhangXueYou",43,new MyDate(1987,5,4));
        Employee e3=new Employee("GuoFuCheng",44,new MyDate(1987,5,9));
        Employee e4=new Employee("LiMing",51,new MyDate(1954,8,12));
        Employee e5=new Employee("LiangChaoWei",21,new MyDate(1978,5,7));
        set.add(e1);
        set.add(e2);
        set.add(e3);
        set.add(e4);
        set.add(e5);



        Iterator iterator = set.iterator();
        while (iterator.hasNext()){
            System.out.println(iterator.next());
        }

    }

    // Question 1 ： Use natural ordering 

//    @Test
//    public void test1(){
//        TreeSet set =new TreeSet();
//
//        Employee e1=new Employee("LiuDeHua",55,new MyDate(1965,5,4));
//        Employee e2=new Employee("ZhangXueYou",43,new MyDate(1987,5,4));
//        Employee e3=new Employee("GuoFuCheng",44,new MyDate(1987,5,9));
//        Employee e4=new Employee("LiMing",51,new MyDate(1954,8,12));
//        Employee e5=new Employee("LiangChaoWei",21,new MyDate(1978,5,7));
//        set.add(e1);
//        set.add(e2);
//        set.add(e3);
//        set.add(e4);
//        set.add(e5);
//        Iterator iterator = set.iterator();
//        while (iterator.hasNext()){
//            System.out.println(iterator.next());
//        }
//
//    }
}