如何使用Jackson处理具有动态根属性键的JSON序列化与反序列化

{
    "random1" : {
        "name" : "john",
        "lastName" : "johnson"
    },
    "nextRandom500" : {
        "name" : "jack",
        "lastName" : "jackson"
    },
    "random100500" : {
        "name" : "jack",
        "lastName" : "johnson"
    }   
}

import com.fasterxml.jackson.annotation.JsonInclude;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.experimental.SuperBuilder;

@Data // Lombok注解，自动生成getter/setter/equals/hashCode/toString
@SuperBuilder(toBuilder=true) // Lombok注解，支持建造者模式，toBuilder允许基于现有对象创建新建造者
@NoArgsConstructor // Lombok注解，生成无参构造函数
@JsonInclude(JsonInclude.Include.NON_NULL) // Jackson注解，序列化时忽略null值字段
public class User {
    private String name;
    private String lastName;
}

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.Map;

public class JsonDeserializationExample {

    public static void main(String[] args) throws JsonProcessingException {
        String jsonString = "{\n" +
                "    \"random1\" : {\n" +
                "        \"name\" : \"john\",\n" +
                "        \"lastName\" : \"johnson\"\n" +
                "    },\n" +
                "    \"nextRandom500\" : {\n" +
                "        \"name\" : \"jack\",\n" +
                "        \"lastName\" : \"jackson\"\n" +
                "    },\n" +
                "    \"random100500\" : {\n" +
                "        \"name\" : \"jack\",\n" +
                "        \"lastName\" : \"johnson\"\n" +
                "    }   \n" +
                "}";

        ObjectMapper objectMapper = new ObjectMapper();

        // 使用TypeReference反序列化到 Map<String, User>
        Map<String, User> usersMap = objectMapper.readValue(jsonString, 
            new TypeReference<Map<String, User>>(){});

        // 打印反序列化结果进行验证
        System.out.println("反序列化结果:");
        usersMap.forEach((key, user) -> 
            System.out.println("  Key: " + key + ", User: " + user.getName() + " " + user.getLastName()));

        /* 预期输出示例:
        反序列化结果:
          Key: random1, User: john johnson
          Key: nextRandom500, User: jack jackson
          Key: random100500, User: jack johnson
        */
    }
}

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.HashMap;
import java.util.Map;

public class JsonSerializationExample {

    public static void main(String[] args) throws JsonProcessingException {
        // 创建一个 Map<String, User> 对象
        Map<String, User> usersToSerialize = new HashMap<>();
        usersToSerialize.put("dynamicKeyA", User.builder().name("Alice").lastName("Smith").build());
        usersToSerialize.put("dynamicKeyB", User.builder().name("Bob").lastName("Johnson").build());

        ObjectMapper objectMapper = new ObjectMapper();

        // 序列化 Map<String, User> 到 JSON 字符串
        String serializedJson = objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(usersToSerialize);

        System.out.println("序列化结果:");
        System.out.println(serializedJson);
        /* 预期输出 (键顺序可能因Map实现而异，但Jackson通常会保持一致或按字母排序):
        序列化结果:
        {
          "dynamicKeyA" : {
            "name" : "Alice",
            "lastName" : "Smith"
          },
          "dynamicKeyB" : {
            "name" : "Bob",
            "lastName" : "Johnson"
          }
        }
        */
    }
}