java元组里面套元组

Java中没有元组（tuple）的概念，但是可以通过使用嵌套类或者数组来实现类似于元组的功能。在Java中嵌套类可以嵌套多层，因此可以创建一个类似于元组里面套元组的结构。举个例子，以下代码实现了一个三元组套四元组的结构：

public class TupleExample {
    public static void main(String[] args) {
        Tuple3<Tuple4<Integer, Integer, Integer, Integer>, Tuple4<Integer, Integer, Integer, Integer>, Tuple4<Integer, Integer, Integer, Integer>> tuple = new Tuple3<>(
                new Tuple4<>(1, 2, 3, 4),
                new Tuple4<>(5, 6, 7, 8),
                new Tuple4<>(9, 10, 11, 12)
        );
        System.out.println(tuple);
    }
}

class Tuple3<A, B, C> {
    public final A a;
    public final B b;
    public final C c;

    public Tuple3(A a, B b, C c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    @Override
    public String toString() {
        return "(" + a.toString() + ", " + b.toString() + ", " + c.toString() + ")";
    }
}

class Tuple4<A, B, C, D> {
    public final A a;
    public final B b;
    public final C c;
    public final D d;

    public Tuple4(A a, B b, C c, D d) {
        this.a = a;
        this.b = b;
        this.c = c;
        this.d = d;
    }

    @Override
    public String toString() {
        return "(" + a.