java元组

public class TwoTuple<A, B> {
    public final A first;
    public final B second;
     
    public TwoTuple(A a, B b) {
        this.first = a;
        this.second = b;
    }
}

public class ThreeTuple<A, B, C> extends TwoTuple<A, B> {
    public final C third;
     
    public ThreeTuple(A a, B b, C c) {
        super(a, b);
        this.third = c;
    }
}