根据条件合并两个列表，并使用java 8将结果推送到映射

import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

List<String> list1 = List.of("A", "B", "C");
List<String> list2 = List.of("C", "D", "E");

List<String> mergedList = Stream.concat(list1.stream(), list2.stream())
        .filter(item -> item.startsWith("C"))
        .collect(Collectors.toList());

Map<String, Integer> resultMap = mergedList.stream()
        .collect(Collectors.toMap(item -> item, item -> item.length()));

import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class Main {
    public static void main(String[] args) {
        List<String> list1 = List.of("A", "B", "C");
        List<String> list2 = List.of("C", "D", "E");

        List<String> mergedList = Stream.concat(list1.stream(), list2.stream())
                .filter(item -> item.startsWith("C"))
                .collect(Collectors.toList());

        Map<String, Integer> resultMap = mergedList.stream()
                .collect(Collectors.toMap(item -> item, item -> item.length()));

        System.out.println(resultMap);
    }
}