今天在看SCJP 6.0認證教戰手冊 (附光碟)讀到86題這樣寫著：Given:10. abstract class A{11. abstract void a1();12. void a2(){}13. }14. class B extends A{15. void a1(){}16. void a2(){}17. }18. class C extends B{void c1(){}}and:A x = new B(); C y = new C(); A z = new C();What are four valid examples of polymorphic method calls? (Choose four.)A. x.a2();B. z.a2();C. z.c1();D. z.a1();E. y.c1();F. x.a1();答案：ACEF 參考：7-9 多型課本的答案寫A...
