如何检查对象是否实现了接口？

Question

如何检查某个类是否实现了接口？当有:

Character.Gorgon gor = new Character.Gorgon();

如何检查gor实现Monster接口？

public interface Monster {

    public int getLevel();

    public int level = 1;
}

public class Character {
    public static class Gorgon extends Character implements Monster {
        public int level;
        @Override
        public int getLevel() { return level; }

        public Gorgon() {
            type = "Gorgon";
        }
    }
}

---

该方法是否getLevel()被Gorgon正确覆盖,因此它可以返回level新gor创建的？

Answer 1

例如

Character.Gorgon gor = new Character.Gorgon();

然后做

gor instanceof Monster

对于Class实例来说

Class<?> clazz = Character.Gorgon.class;
Monster.class.isAssignableFrom(clazz);

Answer 2

使用

if (gor instanceof Monster) {
    //...
}

Answer 3

通常,对于AnInterface和anInstance任何类的:

AnInterface.class.isAssignableFrom(anInstance.getClass());