请定义一个交通工具(Vehicle)的类，其中有: 属性：速度(speed)，体积(size)等等

有不懂后其他详细需求请追问

public class Vehicle{
private int speed;
private int size;
public Vehicle(){
speed=0;
size=0;
}
public Vehicle(int speed,int size){
this.speed=speed;
this.size=size;
}
public void move(){

}
public void setSpeed(int speed){
this.speed=speed;
}
public void setSize(int size){
this.size=size;
}
public void speedUp(){
speed++;
}
public void speedUp(int n){
speed+=n;
}
public void speedDown(){
speed--;
}
public void speedDown(int n){
speed-=n;
}
public String toString(){
return "speed:"+speed+",size:"+size;
}
public static void main(String[] args) {
Vehicle v=new Vehicle();
v.setSpeed(2);
v.setSize(1);
System.out.println(v);
v.speedUp();
System.out.println(v);
v.speedUp(3);
System.out.println(v);
v.speedDown();
System.out.println(v);
v.speedDown(2);
System.out.println(v);
}
}
没问题请采纳