[java] 예제 연습하기

class Shape {
    protected int x, y;

    public void draw() {
        System.out.println("Shape Draw");
    }
}

class Rectangle extends Shape {
    private int width, height;

    public void draw() {
        System.out.println("Rectangle Draw");
    }
}

class Triangle extends Shape {
    private int base, height;

    public void draw() {
        System.out.println("Triangle Draw");
    }
}

class Circle extends Shape {
    private int radius;

    public void draw() {
        System.out.println("Circle Draw");
    }
}

public class ShapeTest {
    public static void main(String[] args) {
        Shape s1, s2;

        s1 = new Shape();       // 당연하다
        s2 = new Rectangle();   // Rectangle 객체를 Shape 변수로 가르킬 수 있을까
    }
}

class Date {
    private int year, month, date;

    public Date(int year, int month, int date) {
        this.year = year;
        this.month = month;
        this.date = date;
    }

    @Override
    public String toString() {
        return "Date [year = " + year + ", month = " + month + ", date = " + date + "]";
    }
}

class Employee {
    private String name;
    private Date birthDate;

    public Employee(String name, Date birthDate) {
        this.name = name;
        this.birthDate = birthDate;
    }

    @Override
    public String toString() {
        return "Employee [name = " + name + ", birthDate = " + birthDate + "]";
    }
}


public class EmployeeTest {
    public static void main(String[] args) {
        Date birth = new Date(1990, 1, 1);
        Employee employee = new Employee("홍길동", birth);
        System.out.println(employee);
    }
}