java - 确定 String 的最长、最长和最长的 ArrayList

Question

我有三 (3) 个不同大小的 ArrayList，我想知道哪个是长的、更长的和最长的。我想出了这个解决方案，效果很好，但看起来还不够优化。我希望有人为我优化它。提前致谢。

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class LongLongerLongest {


    public static void main(String[] args){

        /**
         * Generated ArrayLists for testing
         */
        List<String> first = Arrays.asList("qw", "sd", "asw");
        List<String> second = Arrays.asList("qw", "sd", "r4", "asw", 
"qw", "sd", "r4", "asw", "r4", "asw");
        List<String> third = Arrays.asList("qw", "sd", "r4", "asw", 
"r4", "asw", "oiu");


        String result = sortLists(first,second, third);
        System.out.println(result);
    }



    static String sortLists(List<String> firstList, List<String> 
secondList, List<String> thirdList) {

        /**
         * declare a list to hold all sizes
         */
        List<Integer> listOfSizes = new ArrayList<>();

        List<String> longList;
        List<String> longerList;
        List<String> longestList;

        /**
         * Add the size of all array to the listOfSizes list and sort
         */
        listOfSizes.add(firstList.size());
        listOfSizes.add(secondList.size());
        listOfSizes.add(thirdList.size());
        Collections.sort(listOfSizes);

        /**
         * Searching for the longest
         */
        if (firstList.size() == listOfSizes.get(2)) {
            longestList = firstList;
        }
        else if (secondList.size() == listOfSizes.get(2)) {
            longestList = secondList;
        } else {
            longestList = thirdList;
        }

        /**
         * Searching for the longer
         */
        if (firstList.size() == listOfSizes.get(1)) {
            longerList = firstList;
        }
        else if (secondList.size() == listOfSizes.get(1)) {
            longerList = secondList;
        } else {
            longerList = thirdList;
        }

        /**
         * Searching for the long
         */
        if (firstList.size() == listOfSizes.get(0)) {
            longList = firstList;
        }
        else if (secondList.size() == listOfSizes.get(0)) {
            longList = secondList;
        } else {
            longList = thirdList;
        }

        String result = "long: " + longList.toString() + ", longer: " + 
longerList.toString() + ", longest: " + longestList.toString();
        return result;
    }

}

我上面的内容是为了找到三者的交集。但对于错误处理，我决定从最大的向下排序以避免空列表。

Answer 1

以下是减少代码量的 Stream API 方法:

static String sortLists(List<String> firstList, List<String> secondList, List<String> thirdList) {
     return Stream.of(firstList, secondList, thirdList)
                  .sorted(Comparator.comparingInt(List::size))
                  .collect(collectingAndThen(toList(), f -> "long: " + f.get(0) + ", longer: " +
                         f.get(1) + ", longest: " + f.get(2)));
}

从三个列表创建一个流，然后按其大小排序，最后应用整理函数以获得预期的格式。

需要导入:

import static java.util.stream.Collectors.*;
import java.util.stream.*;