Which class design is better? [closed]

Question

Which class design is better and why?

public class User {     public String UserName;     public String Password;     public String FirstName;     public String LastName; }  public class Employee : User {     public String EmployeeId;     public String EmployeeCode;     public String DepartmentId; }  public class Member : User {     public String MemberId;     public String JoinDate;     public String ExpiryDate; } 

OR

public class User {     public String UserId;     public String UserName;     public String Password;     public String FirstName;     public String LastName; }  public class Employee {     public User UserInfo;     public String EmployeeId;     public String EmployeeCode;     public String DepartmentId; }  public class Member {     public User UserInfo;     public String MemberId;     public String JoinDate;     public String ExpiryDate; } 

Answer 1

The question is simply answered by recognising that inheritance models an "IS-A" relationship, while membership models a "HAS-A" relationship.

• An employee IS A user
• An employee HAS A userinfo

Which one is correct? This is your answer.

Answer 2

I don't like either one. What happens when someone is both a member and an employee?