Java 다형성 - 인터페이스 & 상속

ihongjun@ihongjun-ui-iMac:~/Funny/java/Pure$ tree
.
├── bin
└── src
    └── Goose.java

2 directories, 1 file

ihongjun@ihongjun-ui-iMac:~/Funny/java/Pure$ cat src/Goose.java
interface Flyable {
	public String fly();
}

abstract class Bird implements Flyable {
	public String fly() {
		return "A bird fly";
	}
}

class Owl extends Bird { }

class Chicken extends Bird {
	public String fly() {
		return "Chicken can't fly";
	}
}

public class Goose extends Bird {
	public static void main(String[] args) {
		Flyable[] f = new Flyable[3];
		f[0] = new Chicken();
		f[1] = new Owl();
		f[2] = new Goose();
		for(int x = 0; x < 3; x++) {
			System.out.println(f[x].fly() + " " + f[x].getClass());
		}
	}
}

ihongjun@ihongjun-ui-iMac:~/Funny/java/Pure$ javac -d bin src/Goose.java

ihongjun@ihongjun-ui-iMac:~/Funny/java/Pure$ java -cp bin Goose
Chicken can't fly class Chicken
A bird fly class Owl
A bird fly class Goose

ihongjun@ihongjun-ui-iMac:~/Funny/java/Pure$ tree
.
├── bin
│   ├── Bird.class
│   ├── Chicken.class
│   ├── Flyable.class
│   ├── Goose.class
│   └── Owl.class
└── src
    └── Goose.java

2 directories, 6 files