spring boot 4.* 自定义序列化器的实现

package com.auy.conf;

import org.springframework.boot.jackson.JacksonComponent;
import tools.jackson.core.JacksonException;
import tools.jackson.core.JsonGenerator;
import tools.jackson.core.JsonParser;
import tools.jackson.databind.*;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;

/**
 * Spring Boot 4 兼容的 Jackson 配置
 * 核心适配点：
 * 1. 继承新版ValueSerializer/ValueDeserializer基类
 * 2. 使用@JacksonComponent注解实现组件自动注册
 * 3. 适配Java 8时间类型的序列化/反序列化逻辑
 */
@JacksonComponent//：标记为Jackson组件，Spring Boot 4会自动扫描并注册
public class JacksonConfig {

    // 全局时间格式配置（从AuyConfig读取自定义格式，可根据业务调整为固定格式）
    public static final DateTimeFormatter DATE_FORMATTER = DateTimeFormatter.ofPattern(AuyConfig.get().getDateTimeFormat().getDatePattern());
    public static final DateTimeFormatter TIME_FORMATTER = DateTimeFormatter.ofPattern(AuyConfig.get().getDateTimeFormat().getTimePattern());
    public static final DateTimeFormatter DATE_TIME_FORMATTER = DateTimeFormatter.ofPattern(AuyConfig.get().getDateTimeFormat().getDateTimePattern());

    /**
     * LocalDate 自定义序列化器
     */
    public static class CustomLocalDateSerializer extends ValueSerializer<LocalDate> {
        @Override
        public void serialize(LocalDate v, JsonGenerator g, SerializationContext c) throws JacksonException {
            // 序列化逻辑：LocalDate转指定格式的字符串，null值返回null
            g.writeString(v != null ? DATE_FORMATTER.format(v) : null);
        }
    }

    /**
     * LocalDate 自定义反序列化器
     */
    public static class CustomLocalDateDeserializer extends ValueDeserializer<LocalDate> {
        @Override
        public LocalDate deserialize(JsonParser p, DeserializationContext c) throws JacksonException {
            // 反序列化逻辑：字符串转LocalDate，空值返回null
            String s = p.getValueAsString();
            return s == null || s.isEmpty() ? null : LocalDate.parse(s, DATE_FORMATTER);
        }
    }

    /**
     * LocalTime 自定义序列化器
     */
    public static class CustomLocalTimeSerializer extends ValueSerializer<LocalTime> {
        @Override
        public void serialize(LocalTime v, JsonGenerator g, SerializationContext c) throws JacksonException {
            g.writeString(v != null ? TIME_FORMATTER.format(v) : null);
        }
    }

    /**
     * LocalTime 自定义反序列化器
     */
    public static class CustomLocalTimeDeserializer extends ValueDeserializer<LocalTime> {
        @Override
        public LocalTime deserialize(JsonParser p, DeserializationContext c) throws JacksonException {
            String s = p.getValueAsString();
            return s == null || s.isEmpty() ? null : LocalTime.parse(s, TIME_FORMATTER);
        }
    }

    /**
     * LocalDateTime 自定义序列化器
     */
    public static class CustomLocalDateTimeSerializer extends ValueSerializer<LocalDateTime> {
        @Override
        public void serialize(LocalDateTime v, JsonGenerator g, SerializationContext c) throws JacksonException {
            g.writeString(v != null ? DATE_TIME_FORMATTER.format(v) : null);
        }
    }

    /**
     * LocalDateTime 自定义反序列化器
     */
    public static class CustomLocalDateTimeDeserializer extends ValueDeserializer<LocalDateTime> {
        @Override
        public LocalDateTime deserialize(JsonParser p, DeserializationContext c) throws JacksonException {
            String s = p.getValueAsString();
            return s == null || s.isEmpty() ? null : LocalDateTime.parse(s, DATE_TIME_FORMATTER);
        }
    }
}

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>4.0.0</version>
    <relativePath/>
</parent>

<dependencies>
    <!-- JSON核心依赖（包含Jackson，一般不需要引入，web依赖会自动包含它） -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jackson</artifactId>
    </dependency>
</dependencies>

import com.auy.conf.JacksonConfig;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.time.LocalDateTime;

@SpringBootTest
public class JacksonSerializerTest {

    @Autowired
    private ObjectMapper objectMapper;

    @Test
    public void testLocalDateTimeSerializer() throws Exception {
        LocalDateTime now = LocalDateTime.now();
        // 序列化
        String json = objectMapper.writeValueAsString(now);
        System.out.println("序列化结果：" + json);
        // 反序列化
        LocalDateTime parsed = objectMapper.readValue(json, LocalDateTime.class);
        System.out.println("反序列化结果：" + parsed);
    }
}

@JacksonComponent
public static class CustomEnumSerializer extends ValueSerializer<YourEnum> {
    @Override
    public void serialize(YourEnum v, JsonGenerator g, SerializationContext c) throws JacksonException {
        // 自定义枚举序列化逻辑，如返回枚举的描述值
        g.writeString(v != null ? v.getDesc() : null);
    }
}

@JacksonComponent
public static class CustomEnumDeserializer extends ValueDeserializer<YourEnum> {
    @Override
    public YourEnum deserialize(JsonParser p, DeserializationContext c) throws JacksonException {
        String s = p.getValueAsString();
        // 自定义枚举反序列化逻辑
        return s == null ? null : YourEnum.getByDesc(s);
    }
}