現(xiàn)有:
class Pencil {
public void write (String content){ System.out.println ("Write"+content); } }
class RubberPencil extends Pencil{ public void erase (String content){ System.out.println ("Erase"+content); } }
執(zhí)行下列代碼的結(jié)果是哪項(xiàng)?()
Pencil pen=new RubberPencil();
pen.write ("Hello");
pen.erase ("Hello");
A. Write Hello Erase Hello
B. Erase Hello Write Hello
C.編譯錯(cuò)誤
D.運(yùn)行時(shí)拋出異常
A. as
B. is
C. instanceof
D. extends