今天群友问了个问题，关于 LocalDateTime 序列化的问题

这里记录下解决办法

1、添加依赖

<dependency>
	<groupId>com.fasterxml.jackson.datatype</groupId>
	<artifactId>jackson-datatype-jsr310</artifactId>
	<version>2.8.9</version>
</dependency>

2、添加配置

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

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

@Configuration
public class MvcConfig {

    @Bean
    public ObjectMapper initObjectMapper() {
        ObjectMapper objectMapper = new ObjectMapper();

        JavaTimeModule javaTimeModule = new JavaTimeModule();
        javaTimeModule.addDeserializer(LocalDateTime.class, new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        javaTimeModule.addSerializer(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        // localDateTime按照 "yyyy-MM-dd HH:mm:ss"的格式进行序列化、反序列化
        objectMapper.registerModule(javaTimeModule);

        return objectMapper;
    }
}

3、测试

1）创建实体类

import lombok.Data;
import org.springframework.format.annotation.DateTimeFormat;

import java.time.LocalDateTime;


@Data
public class User {

    @DateTimeFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private LocalDateTime localDateTime = LocalDateTime.now();
}

2）控制器，分别演示返回和接收参数

import com.example.demo.dto.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class DemoController {


    /**
     * 返回参数 序列化测试
     * @return
     * @throws Exception
     */
    @GetMapping("/test")
    public User test() throws Exception {
        User user = new User();;
        return user;
    }


    /**
     * 入参测试 反序列化测试
     * {
     *     "localDateTime": "2022-10-12 00:10:30"
     * }
     * @param user
     * @return
     * @throws Exception
     */
    @PostMapping("/test2")
    public User test(@RequestBody User user) throws Exception {
        return user;
    }

}

3）效果图