不能够访问受保护的字段或方法在子调用

Question

我的程序如下：

package pack1; 

public class Parent { 
int i=0; 
protected j =1; 
public k = 2; 
} 

package pack2; 

import pack1.Parent; 
public class Child extends Parent { 

public static void main (String args[]) { 
    Child c1 = new Child(); 
    c1.j = 100; // This is working fine 

    Parent c2 = new Child(); 
    c2.j=200; // Compilation error 

} 
} 

我的问题是：为什么我们也不能够与“C2”访问保护成员在父类。

Answer 1

不能与被争论的答案为“是因为规范是这么说的”：

A protected member of a base class is accessible in a derived class only if the access occurs through the derived class type. 

，你将不得不作出成员内部（或公共）。