java - 如果我的实例是一个数组，我如何设置它的数组类型变量的值

Question

我有一个名为 Combination 的类，它有一个数组类型变量。我想做的是将 x (预定义)数量的对象放入数组中。让我困惑的是我的实例和它的变量都是数组。我是否需要一维数组来在其中放置对象，或者由于我的变量是数组，所以它必须是二维的吗？

public class Combination {
    public int[] combination = new int[6];

    public Combination(int[] combination) {
        super();
        this.combination = combination;
    }

    public Combination() {
        super();
    }
}

public class Glavna {
    static Scanner s = new Scanner(System.in);

    public static void main(String[] args) {
        System.out.println("Enter number of combinations");
        int combNum = s.nextInt();
        Combination k = new Combination();
        Combination[] array1 = new Combination[combNum];  // which one of these 2 is correct
        Combination[][] array2 = new Combination[combNum][6];  // which one of these 2 is correct
        k.kombinacija[3] = 5;         // This works fine
        array1[0].combination = 1;      //  This throws NullPointerException
        array2[0][0].combination[0] = 1;    //  This throws NullPointerException
    }
}

输入:2
1 2 3 4 5 6 7 8 9 10 11 12
所需输出:
1 2 3 4 5 6
7 8 9 10 11 12

如果输出被称为final[]，那么final[1]是第一行，final[2]是第二行。

谢谢。

Answer 1

请检查此答案是否对您有帮助:

public class Glavna {
static Scanner s = new Scanner(System.in);

public static void main(String[] args) {

    System.out.println("Enter number of combinations");
    int combNum = s.nextInt();
    Combination k = new Combination();
    Combination combination1 = new Combination();  // Combination object 1
    Combination combination2 = new Combination();  // Combination object 2
    System.out.println("Enter inputs");
    for (int i = 0; i < combNum; i++) {
        if (i <= 5) {
            combination1.combination[i] = s.nextInt(); // Assign input set 1 to combination object 1 array
        } else {
            combination2.combination[i-6] = s.nextInt(); // Assign input set 2 to combination object 2 array
        }
    }

    //Print output separately
    System.out.println("Desired output: ");
    for (int l : combination1.combination) {
        System.out.print(l + " ");
    }
    System.out.println();
    for (int l : combination2.combination) {
        System.out.print(l + " ");
    }
}
}