一.題目
Given:
| class Vehicle{ | |
| Vehicle() { | |
| System.out.println("Vehicle"); | |
| } | |
| } | |
| class Bus extends Vehicle { | |
| Bus() { | |
| System.out.println("Bus"); | |
| } | |
| } | |
| public class Transport { | |
| public static void main(String[] args) { | |
| Vehicle v = new Bus(); | |
| } | |
| } |
What is the result?
A. Vehicle Bus
B. Bus Vehicle
C. Bus
D. The program doesn't print anything
二.答案
A
三.解析
- 建立子類別物件
- 先呼叫父類別無參數的建構方法，印出 Vehicle
- 呼叫子類別無參數的建構方法，印出 Bus
四.參考資料
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