已知：class Employee;class Manager extends Employee;class Director extends Employee;则以下语句能通过编译的有哪些？
A: Employee e = new Manager();
B: Director d = new Manager();
C: Director d = new Employee();
D: Manager m = new Director()
A: Employee e = new Manager();
B: Director d = new Manager();
C: Director d = new Employee();
D: Manager m = new Director()
举一反三
- class Employee; class Manager extends Employee; class Director extends Employee;
- 已知类的继承关系 class Employee; class Manager extends Employee; class Director extands Employee; class Director extands Employee; 下语句能通过编译的有哪些?
- 已知类的继承关系如下： A: Employee e=new Manager(); B: Director d=new Manager(); C: Director d=new Employee(); D: Manager m=new Director();
- 已知类的继承关系如下： class Employee; class Manager extends Employee; class Director extends Employee; 则以下语句能通过编译的有哪些？
- 已知类关系如下:ClassEmployee{}ClassManagerextendsEmployee{}ClassDirectorextendsEmployee{}则下列语句正确的是:()。 A: Employee e=new Manager(); B: Director d=new Manager(); C: Director d =new Employee (); D: Manager m=new Director ();