public void problem1()
{
AbstractClassRoomUserFactory factory = new OrdinaryClassRoomUserFactory();
IClassRoomUser student = factory.createStudent();
IUserIdentity idCard = new OrdinaryIdCard("987231");
student.SetIdentity(idCard);
idCard = new InternationalIdCard("1234567");
student.SetIdentity(idCard); // <- without Compile-time Error
}
public void doExit(string arg0, string arg1)
{
AbstractClassRoomUserFactory factory = new OrdinaryClassRoomUserFactory();
if (arg0 == "International")
{
factory = new InternationalClassRoomUserFactory();
}
IClassRoomUser person = factory.createClassRoomUser(arg1);
person.Exit();
}
