fastjson 自定义序列化

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.ObjectSerializer;
import java.io.IOException;
import java.lang.reflect.Type;

public class CustomSerializerExample {

    public static void main(String[] args) {
        User user = new User("John", "Doe");
        String jsonString = JSON.toJSONString(user, new UserSerializer());
        System.out.println(jsonString); // 输出: {"lastName":"Doe","firstName":"John"}
    }

    static class User {
        private String firstName;
        private String lastName;

        public User(String firstName, String lastName) {
            this.firstName = firstName;
            this.lastName = lastName;
        }

        // getters and setters...
    }

    static class UserSerializer implements ObjectSerializer {
        @Override
        public void write(JSONSerializer serializer, Object object, Object fieldName, Type fieldType, int features) throws IOException {
            if (object instanceof User) {
                User user = (User) object;
                serializer.write(new String[]{user.getLastName(), user.getFirstName()});
            }
        }
    }
}