Equals.java

class Equals {
    public static void main(String[] args) {
        Car car1 = new Car(12345);
        Car car2 = new Car(12345);
        Car car3 = car1;

        System.out.println(car1.equals(car2));
        System.out.println(car1.equals(car3));
    }
}

class Car {
    protected int speedMax = 100;
    private long id;

    public Car(long id) {
        this.id = id;
    }

    public Car() {

    }

    public int getSpeedMax() {
        return speedMax;
    }

    public String toString() {
        return "This is car";
    }
}

class SportCar extends Car {
    protected int speedMax = 300;

    public int getSpeedMax() {
        return speedMax;
    }
}