java - 如何在构造函数中使用 Car 对象引用？

Question

我正在练习制作自己的类(class)，最终我想制作一个包含这 3 辆车的车队并计算平均 MPG。我在将汽车加入车队时遇到了麻烦。我认为我的问题在于实例变量，但我不知道该怎么做。

import java.util.Scanner;

class CarFleet {

    Car car1;
    Car car2;
    Car car3;

    CarFleet(first, second, third) {
        car1 = first;
        car2 = second;
        car3 = third;
    }
}

<小时/>

class Car {

    double startMiles;
    double endMiles;
    double gallons;

    Car(double initialMiles, double endingMiles, double tankGals) {
        startMiles = initialMiles;
        endMiles = endingMiles;
        gallons = tankGals;
    }

    public double calculateMPG() {
        return (endMiles - startMiles) / gallons;
    }
}

<小时/>

class MPG {

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);
        //System.out.println("Initial miles for trip: ");
        //double initMiles = scan.nextDouble();
        //System.out.println("End miles for trip: ");
        //double endMiles = scan.nextDouble();
        //System.out.println("Gallons used for trip: ");
        //double gals = scan.nextDouble();

        Car Lambo = new Car(0, 335, 9.5);
        String car1 = "Lambo";
        System.out.println("Your " + car1 + " goes " + Lambo.calculateMPG() + "        MPG");

        Car Honda = new Car(0, 24, 2);
        String car2 = "Honda";
        System.out.println("Your " + car2 + " goes " + Honda.calculateMPG() + " MPG");

        Car Eclipse = new Car(0, 48, 3);
        String car3 = "Eclipse";
        System.out.println("Your " + car3 + " goes " + Eclipse.calculateMPG() + " MPG");

        CarFleet coolCars = new CarFleet(Lambo, Honda, Eclipse);
    }
}

Answer 1

像这样

CarFleet(Car first, Car second,Car third) {
 this.car1 = first;
 this.car2 = second;
 this.car3 = third;
}