SCJP題庫第043題


1. class Plant{
2.   private String name;
3.   public Plant(String name){this.name = name;}
4.   public String getName(){return name;}
5. }
6. public class Tree extends Plant{
7.   public void growFruit(){}
8.   public void dropLeaves(){}
9. }

What statement is true?
A. The code will compile without changes.
B. The code will compile if public Tree(){Plant();} is added to the Tree class.
C. The code will compile if public Plant(){Tree();} is added to the Plant class.
D. The code will compile if public Plant(){this("fern");} is added to the Plant class.
E. The code will compile if public Plant(){Plant("fern");} is added to the Plant class.

Ans:D

解說:
Tree的預設建構子有super(),父類別必須有無參數的建構子

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