상속과 생성자

자손 클래스의 생성자 작업을 할 때 부모 클래스의 생성자도 반드시 호출해주어야 합니다. 

package chapter07;

public class exam43 {

	public static void main(String[] args) {
		exam43_SportsCar sportsCar1 = new exam43_SportsCar("red",330);
		
		System.out.println(sportsCar1.color);
		System.out.println(sportsCar1.speedLimit);
	}

}

package chapter07;

public class exam43_Car2 {
	int wheel;
	int speed;
	String color;
	
	exam43_Car2() {};
	
	exam43_Car2 (String color) {
		this.color = color;
	}
}

package chapter07;

public class exam43_SportsCar extends exam43_Car2 {
	int speedLimit;
	
	exam43_SportsCar (String color, int speedLimit) {
		super();
		this.color = color;
		this.speedLimit = speedLimit;
	}
}