用于将JSON列表聚合到组中的Java流

import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class JsonGroupingExample {
    public static void main(String[] args) {
        // 假设有一个JSON列表
        String json = "[{\"name\":\"Alice\",\"age\":25},{\"name\":\"Bob\",\"age\":30},{\"name\":\"Alice\",\"age\":35}]";

        try {
            // 将JSON转换为Java对象列表
            ObjectMapper objectMapper = new ObjectMapper();
            List<Map<String, Object>> jsonList = objectMapper.readValue(json, List.class);

            // 使用Java流将JSON列表按照name属性分组
            Map<String, List<Map<String, Object>>> groupedMap = jsonList.stream()
                    .collect(Collectors.groupingBy(obj -> (String) obj.get("name")));

            // 输出每个组的结果
            groupedMap.forEach((name, group) -> {
                System.out.println("Group: " + name);
                group.forEach(System.out::println);
                System.out.println();
            });
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}