java - 错误: " is not abstract and does not override abstract method "

Question

错误:

java:com.company.Bicycle is not abstract and does not override abstract method applyBreakes(int) in com.company.Vehicle and same for the Bike class.

package com.company;

interface Vehicle {

//all are the abstract method.
void changeGear(int a);
void speedUp(int a);
void applyBreakes(int a);
}



class Bicycle implements Vehicle {

int speed;
int gear;

//to change speed
@Override
public void changeGear(int newGear) {

    gear = newGear;

}

//to increase speed
@Override
public void speedUp(int increment) {

    speed = speed + increment;

}

//to decrease speed
public void applyBreaks(int decrement) {

    speed = speed - decrement;

}

public  void  printStates() {

    System.out.println("speed: " + speed + " gear: " + gear);
}

}

class Bike implements  Vehicle {

int speed;
int gear;

//to change gear
@Override
public void changeGear(int newGear) {

    gear = newGear;

}

//to increase speed
@Override
public void speedUp(int increment) {

    speed = speed + increment;

}

//to decrease speed
public void applyBreaks(int decrement) {

    speed = speed - decrement;

}

public void printStates() {

    System.out.println("speed: " + speed + " gear: " + gear);
}

}




class GFG {

public static void main(String[] args) {

    //creating an instance of Bicycle
    //doing some operations
    Bicycle bicycle = new Bicycle();
    bicycle.changeGear(2);
    bicycle.speedUp(3);
    bicycle.applyBreaks(1);

    System.out.println("Bike present state :");
    bicycle.printStates();

    //creating instance of bike.
    Bike bike = new Bike();
    bike.changeGear(1);
    bike.speedUp(4);
    bike.applyBreaks(3);

    System.out.println("Bike present state :");
    bike.printStates();

}
}

Answer 1

因为您在接口(interface)(和/或实现)中拼错了方法名称。

接口(interface)方法名称为applyBreaks，而实现则将其称为applyBreaks。因此，这些类不会实现接口(interface)方法，而是定义新的(不相关的)方法。

<小时/>

附注正确的拼写(英语)是“applyBrakes”。