java一个类里面写两个类

编写一个 java 应用程序，该程序中有两个类Vehicle(用于描述机动
车），一个主类User，其中 Vehicle 的speed 属性用于描述速度,power用于描述功率，setSpeed 方法用于设定机动车的速度值，setPower
用于设定机动车的功率，getSpeed 和 getPower 用于获取机动车的速度和功率，speedUp 和 speedDown 方法用于描述机动车的加速和减速情况。
Vehicle
speed: double
power: int
setSpeed (double): void
getSpeed (): double
speedUp (int): void
speedDown (int): void
setPower (int):
void
getPower (): int

public class Test {
    
    public static class Vehicle{
        
        private double speed;
        private int power;

        public double getSpeed() {
            return speed;
        }

        public void setSpeed(double speed) {
            this.speed = speed;
        }

        public int getPower() {
            return power;
        }

        public void setPower(int power) {
            this.power = power;
        }
        
        public void speedUp(double speedUp) {
            this.speed = speedUp;
        }

        public void speedDown(double speedDown) {
            this.speed = speedDown;
        }
    }

    public static class User{

    }
}

这看上去像是大学作业，建议你如果想做这行自己做，不想做这行就尽早转专业，不浪费自己的时间
public class Vehicle{
private double speed;
private int power;
public void setSpeed(double speed){this.speed=speed;}
public void setPower(int power){this.power=power;}
public double getSpeed(){return this.speed;}
public int getPower(){return this.power;}
}
speedUp 和speedDown 没看懂意思，我也是java新手，估计大概代码就这样吧。如果有正确答案可以提醒我看一下，谢谢

class Vehicle {
    private double speed;
    private int power;

    public Vehicle(double speed, int power) {
        this.speed = speed;
        this.power = power;
    }

    public double getSpeed() {
        return speed;
    }

    public void setSpeed(double speed) {
        this.speed = speed;
    }

    public int getPower() {
        return power;
    }

    public void setPower(int power) {
        this.power = power;
    }

    public void speedUp(){
        System.out.println("汽车正在加速行驶中！");
    }

    public void speedDown(){
        System.out.println("汽车正在减速中！");
    }
}
public class User{

}