SCJP題庫第101題

Given:

10. package com.sun.scjp;

11. public class Geodetics {

12. public static final double DIAMETER = 12756.32; //kilometers

13. }

Which two correctly access the DIAMETER member of the Geodetics class? (Choose two.)

 

 

A. import com.sun.scjp.Geodetics;

public class TerraCarta{

public double halfway()

{return Geodetics.DIAMETER/2.0;}

B. import static com.sun.scjp.Geodetics;

public class TerraCarta{

public double halfway(){return DIAMETER/2.0;}}

 C import static com.sun.scjp.Geodetics.*;

public class TerraCarta{

public double halfway(){return DIAMETER/2.0;}}

D. package com.sun.scjp;

public class TerraCarta{

public double halfway(){return DIAMETER/2.0;}}

 

Ans: AC

 

解說:

DIAMETER是類別成員，使用時應該是用：類別名.類別成員名字，如A

import static可以簡化使用類別成員時的”類別名.”，可以直接叫用類別成員，如C