java 写一个类:机动车 { 成员变量:发动机:String(型号) 车轱辘:int 方法:获取轱辘:返回车轱辘数量 设置轱辘:设置车轱辘数 ②主类名为:Test 用机动车创建对象:三轮车，小汽车分别设置三轮车和小汽车轱辘数 输出三轮车和小汽车的发动机和车轱辘

好的，以下是你需要的代码：

class MotorVehicle {
    private String engine;
    private int wheels;

    public int getWheels() {
        return wheels;
    }

    public void setWheels(int wheels) {
        this.wheels = wheels;
    }

    public String getEngine() {
        return engine;
    }

    public void setEngine(String engine) {
        this.engine = engine;
    }
}

public class Test {
    public static void main(String[] args) {
        MotorVehicle tricycle = new MotorVehicle();
        tricycle.setWheels(3);
        tricycle.setEngine("三轮车发动机型号");
        System.out.println("三轮车发动机型号：" + tricycle.getEngine() + "，车轱辘数量：" + tricycle.getWheels());

        MotorVehicle car = new MotorVehicle();
        car.setWheels(4);
        car.setEngine("小汽车发动机型号");
        System.out.println("小汽车发动机型号：" + car.getEngine() + "，车轱辘数量：" + car.getWheels());
    }
}

希望能够帮到你！