java对象转JSON字符串不乱序的问题解决

import com.fasterxml.jackson.annotation.JsonPropertyOrder;
import com.fasterxml.jackson.databind.ObjectMapper;
 
import java.io.IOException;
 
// 使用 @JsonPropertyOrder 注解指定属性顺序
@JsonPropertyOrder({"id", "name", "age"})
class Person {
    private int id;
    private String name;
    private int age;
 
    public Person(int id, String name, int age) {
        this.id = id;
        this.name = name;
        this.age = age;
    }
 
    // Getters and Setters
    public int getId() {
        return id;
    }
 
    public void setId(int id) {
        this.id = id;
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public int getAge() {
        return age;
    }
 
    public void setAge(int age) {
        this.age = age;
    }
}
 
public class JacksonExample {
    public static void main(String[] args) {
        Person person = new Person(1, "John", 30);
        ObjectMapper objectMapper = new ObjectMapper();
        try {
            // 将对象转换为 JSON 字符串
            String json = objectMapper.writeValueAsString(person);
            System.out.println(json);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
 
import java.util.LinkedHashMap;
import java.util.Map;
 
class Person {
    private int id;
    private String name;
    private int age;
 
    public Person(int id, String name, int age) {
        this.id = id;
        this.name = name;
        this.age = age;
    }
 
    // Getters and Setters
    public int getId() {
        return id;
    }
 
    public void setId(int id) {
        this.id = id;
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public int getAge() {
        return age;
    }
 
    public void setAge(int age) {
        this.age = age;
    }
}
 
public class GsonExample {
    public static void main(String[] args) {
        Person person = new Person(1, "John", 30);
        // 创建一个 LinkedHashMap 来保持属性顺序
        Map<String, Object> personMap = new LinkedHashMap<>();
        personMap.put("id", person.getId());
        personMap.put("name", person.getName());
        personMap.put("age", person.getAge());
 
        Gson gson = new GsonBuilder().create();
        // 将 LinkedHashMap 转换为 JSON 字符串
        String json = gson.toJson(personMap);
        System.out.println(json);
    }
}