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单选题
下列选项中,能实现对父类的getSalary方法重写的是( )。
class Employee{
public double getSalary(){}
}
A
class Manager extends Employee{
public int getSalary(double x){}
}
B
class Manager extends Employee{
public double getSalary(int x,int y){}
}
C
class Manager extends Employee{
public double getSalary(){}
}
D
class Manager extends Employee{
public int getSalary(int x,int y){}
}
参考答案
参考解析
解析:
对一个类的继承是指在现有类(父类)的基础上构建一个新类(子类),子类重用(继承)了父类的方法和属性(该属性和方法不能被private修饰),同时还可以向新类中增添新的方法的状态。所以,在子类中可以进行的操作是添加方法。但是不能减少或更换父类的方法。在对父类的方法进行重写的时候,方法的返回值、返回值类型、参数个数、相应的参数类型都要一一对应,所以对父类的getSalary方法重写的时候,返回值的类型应该是double,没有参数。
更多 “单选题下列选项中,能实现对父类的getSalary方法重写的是( )。 class Employee{ public double getSalary(){} }A class Manager extends Employee{ public int getSalary(double x){} }B class Manager extends Employee{ public double getSalary(int x,int y){} }C class Manager extends Employee{ public double getSalary(){} }D class Manager extends Employee{ public int getSalary(int x,int y){} }” 相关考题
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class A { public A(int x) {} }B
class A {} class B extends A { B() {} }C
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