断言两个列表具有相同的长度。创建所有姓名和姓氏的列表

Question

    static List<String> ex2(List<String> names, List<String> surnames) {
        if (names.size() != surnames.size()) {
    throw new IllegalArgumentException("the two lists are not the same length");
    }
    List<String> n = names.stream().map(e -> 
    e.toUpperCase()).collect(Collectors.toList());
    surnames.stream().map(e -> n.add(e)).collect(Collectors.toList());
    return n;
    }

List<String> fname = List.of("A", "B", "C", "D", "E", "F");
List<String> lname = List.of("G", "H", "I", "J", "K", "L");

输出:[A,B,C,D,E,F,G,H,I,J,K,L]

Answer 1

您可以使用stream.concat()和stream.sorted()函数。例如：

    public static void main(String[] args) {
        List<String> fname = List.of("A", "B", "C", "D", "E", "F");
        List<String> lname = List.of("G", "H", "I", "J", "K", "L");
        List<String> together = Stream.concat(fname.stream(), lname.stream()).sorted().collect(Collectors.toList());
        System.out.println(together);
    }