java - 如何使用另一个数组中的对象初始化新数组(我获取地址，而不是值)

Question

我在初始化数组时遇到问题。它显示了一个新的内存地址数组，而不是值。我错了，但我找不到错误。这可能很容易，但我希望你能帮助我。

public static void searchCarByBrand(Car[] cars, char ch) {

    System.out.println("the method searchCarByBrand was called with ch = " + ch);
    int carsLenght = cars.length;
    Car[] carsArray = new Car[carsLenght];

    for(Car aCars : cars) {
        System.out.println("this is for each");

        if(getBrand().charAt(0) == ch) {
            System.out.println("this is if");

            for(int i = 0; i< carsArray.length; i++) {
                carsArray[i] = new Car();
                System.out.println("carsArray[" + i + "]: " + carsArray[i]);
            }
        }
    }
}
public class Car {
private static String brand;
private String model;
// private String model;
private String color;
private int horsePower;
private String engineType;
private String gearBoxType;
private String dateOfManufacture;

}

   public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    Car car1 = new Car("Mercedes", "slk", "blue", 199, "bnz", "r",
            "18 August 2005");
    Car car2 = new Car("peugeot", "206 cc", "blue", 165,"bnz", "r", "200");
    Car car3 = new Car("peugeot", "206" , "red", 155, "bnz", "r", "2005");

    Car[] carArray = new Car[3];
    carArray[0] = car1;
    carArray[1] = car2;
    carArray[2] = car3;

    System.out.println("this is the result from the 1st method:");
    System.out.println("enter brand:");
    char ch =  scan.next().charAt(0);
    searchCarByBrand(carArray,ch);

}

Answer 1

如果您想在控制台上打印，请尝试在汽车类中添加 public String toString() 方法。
另外，在您的数组中，您添加了一个空的汽车对象，因此它不会打印任何值

carsArray[i] = new Car(); System.out.println("carsArray[" + i + "]: " + carsArray[i]);

在汽车类中添加toString方法

    @Override
public String toString() {
    return "Car{" +
            "model='" + model + '\'' +
            ", color='" + color + '\'' +
            ", horsePower=" + horsePower +
            ", engineType='" + engineType + '\'' +
            ", gearBoxType='" + gearBoxType + '\'' +
            ", dateOfManufacture='" + dateOfManufacture + '\'' +
            '}';
}

代码中似乎存在一些逻辑错误
if(aCars.getBrand().charAt(0) == ch)
和
carsArray[i] = new Car() aCars;

for(Car aCars:汽车) { System.out.println("这是针对每个的");

    if(aCars.getBrand().charAt(0) == ch) {
        System.out.println("this is if");

        for(int i = 0; i< carsArray.length; i++) {
            carsArray[i] = aCars;
            System.out.println("carsArray[" + i + "]: " + carsArray[i]);
        }
    }
}

}