[게임 프로그래밍 패턴] 4. 프로토타입 패턴

프로토타입 패턴 (Prototype Pattern)

기본 원형이 되는 인스턴스를 사용해서 생성할 객체의 종류를 명시하고 이렇게 만들어진 객체를 복사해서 새로운 객체를 생성하는 패턴
89 : 핵심은 어떤 객체가 자기와 비슷한 객체를 스폰할 수 있다는 점이다.

public abstract class Monster {
    int health_, speed_;
    Monster(int health, int speed) {
        this.health_ = health;
        this.speed_ = speed;
    }
    public abstract Monster clone() throws CloneNotSupportedException;
    public void print() {
        System.out.println(this.getClass() + " health_ = " + health_ + " speed_ = " + speed_);
    }
}

public class Ghost extends Monster {
    public Ghost(int health, int speed) {
        super(health, speed);
    }
    @Override    
    public Monster clone() throws CloneNotSupportedException {
        return new Ghost(health_, speed_);
    }
}

public class Demon extends Monster {
    public Demon(int health, int speed) {
        super(health, speed);
    }
    @Override    
    public Monster clone() throws CloneNotSupportedException {
        return new Demon(health_, speed_);
    }
}

public class Sorcerer extends Monster {
    public Sorcerer(int health, int speed) {
        super(health, speed);
    }
    @Override    
    public Monster clone() throws CloneNotSupportedException {
        return new Sorcerer(health_, speed_);
    }
}

public class Spawner {
    private final Monster monster;
    public Spawner(Monster monster) {
        this.monster = monster;
    }
    public Monster spawn() throws CloneNotSupportedException {
        return monster.clone();
    }
}

public class Main {
    public static void main(String[] args) throws CloneNotSupportedException {
        Demon demon = new Demon(15, 15);
        Spawner demonSpawner = new Spawner(demon);

        Ghost ghost = new Ghost(5, 20);
        Spawner ghostSpawner = new Spawner(ghost);

        Sorcerer sorcerer = new Sorcerer(20, 10);
        Spawner sorcererSpawner = new Spawner(sorcerer);

        demonSpawner.spawn().print();
        ghostSpawner.spawn().print();
        sorcererSpawner.spawn().print();
    }
}

// 실행결과
class prototype.Demon health_ = 15 speed_ = 15
class prototype.Ghost health_ = 5 speed_ = 20
class prototype.Sorcerer health_ = 20 speed_ = 10