模糊的JAVA接口

Question

如何定义类/接口Adult，Student和Engineer，以便下一个序列只在指定的地方给出编译错误？

class Test {
public static void main(String args[]) {
Adult a = new Student(); //without giving compilation error
Adult b = new Engineer();//without giving compilation error
a.explorare(); //without giving compilation error
b.explorare(); //without giving compilation error
a.afisare(); //without giving compilation error
b.afisare(); //compilation error

Answer 1

这是不可能的，如果a.afisare()编译那么b.afisare()也是如此。