泛型+集合+比较的练习

public class test{
    public static void main(String[] args) {

        ArrayList<Employee> employees = new ArrayList();

        employees.add(new Employee("tom",2200,new Mydate(2002,8,1)));
        employees.add(new Employee("milan",2000,new Mydate(2010,5,1)));
        employees.add(new Employee("jack",4400,new Mydate(1998,4,1)));
        employees.add(new Employee("john",1000,new Mydate(2001,10,1)));

        employees.sort(new Comparator<Employee>() {
            @Override
            public int compare(Employee o1, Employee o2) {

                if(!(o1 instanceof Employee && o2 instanceof Employee)){
                    return 0;
                }

//                int i = o1.getName().compareTo(o2.getName());
//                if(i != 0){
//                    return i;
//                }

                int j = o1.getName().length() - o2.getName().length();
                if(j != 0){
                    return j;
                }

                int i1 = o1.getBirthday().getYear() - o2.getBirthday().getYear();
                if(i1 != 0){
                    return i1;
                }
                int i2 = o1.getBirthday().getMonth() - o2.getBirthday().getMonth();
                if(i2 != 0){
                    return i2;
                }
                return o1.getBirthday().getDay() - o2.getBirthday().getDay();

            }
        });
        Iterator<Employee> iterator = employees.iterator();
        while (iterator.hasNext()) {
            Employee employee =  iterator.next();
            System.out.println(employee);

        }
    }
}

class Mydate{

    private int year;
    private int month;
    private int day;

    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 +
                '}';
    }
}
class Employee implements Comparable<Employee>{
    private String name;
    private double sal;
    private Mydate birthday;

    public Employee(String name, double sal, Mydate birthday) {
        this.name = name;
        this.sal = sal;
        this.birthday = birthday;
    }

    public String getName() {
        return name;
    }

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

    public double getSal() {
        return sal;
    }

    public void setSal(double sal) {
        this.sal = sal;
    }

    public Mydate getBirthday() {
        return birthday;
    }

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

    @Override
    public int compareTo(Employee o) {
        return Double.compare(this.getSal(),o.getSal());
    }

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