SpringBoot利用jackson格式化时间的三种方法

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-WEB</artifactId>
</dependency>

private String id;
private String username;
private Date createTime;

@RestController
public class UserController {
    @GetMapping("/getUser")
    public List<UserDTO> getUser() {
        List<UserDTO> userList = new ArrayList<UserDTO>();
        for (int i=1; i<=3; i++) {
            UserDTO user = new UserDTO();
            user.setCreateTime(new Date());
            user.setUsername("Gongj" + i);
            user.setId("j" + i);
            userList.add(user);
        }
        return userList;
    }
    
}

import com.fasterxml.jackson.annotation.jsonFormat;

private String id;
private String username;
 @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss",timezone = "GMT+8")
private Date createTime;

@Bean
@ConditionalOnMissingBean(
	value = {MappingJackson2HttpMessageConverter.class},
	ignoredType = {"org.springframework.hateoas.server.mvc.TypeConstrainedMappingJackson2HttpMessageConverter", "org.springframework.data.rest.webmvc.alps.AlpsJsonHttpMessageConverter"}
)
MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter(ObjectMapper objectMapper) {
	return new MappingJackson2HttpMessageConverter(objectMapper);
}

import java.text.SimpleDateFormat;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.fasterxml.jackson.databind.ObjectMapper;

@Configuration
public class MyConfig {

    @Bean
    MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverterConfiguration() {
        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        ObjectMapper om = new ObjectMapper();
        //全局修改josn时间格式
        om.setDateFormat(new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"));
        converter.setObjectMapper(om);
        return converter;
    }
}

import java.text.SimpleDateFormat;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.fasterxml.jackson.databind.ObjectMapper;
@Bean
ObjectMapper objectMapper() {
	ObjectMapper om = new ObjectMapper();
	om.setDateFormat(new SimpleDateFormat("yyyy-MM-dd"));
	return om;
}

spring: 
  jackson: 
    date-format: yyyy/MM/dd
    timezone: GMT+8

spring.jackson.date-format=yyyy-MM-dd HH:mm
spring.jackson.time-zone=GMT+8