讓有下面的類圖作爲例子接口和Java中的類
我做了Java中類似的類像下面
public class B {
}
public interface C {
}
public class A extends B implements C {
}
public class D {
C c = new A();
C c1 = new B(); // Error, Type mismatch: cannot convert from B to C. WHY ?
C c2 = (C) new B(); // Works fine. This makes me confuse ... What does this actually mean ?
}
任何人能解釋一下嗎?
爲什麼我的問題是downvoted? – Junaid
@Junaid忽略那些沒有評論的downvotes。 –