spring.jackson properties not found - serialization

Question

In my Spring Boot project it seems none of the spring.jackson properties are working. I want to take controll over date fields and I tried to add the following properties to my application.properties file:
spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS=false
spring.jackson.date-format=yyyy-MM-dd HH:mm:ss
spring.jackson.joda-date-time-format=yyyy-MM-dd HH:mm:ss
Dates still come as timestamps (java.util.Date and joda.time). I have the following dependencies:
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jdk8</artifactId>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jsr310</artifactId>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-joda</artifactId>
</dependency>
I didn't add version number but it says the managed version number is 2.8.7 (with all three).
I've read if I use #EnableWebMvc annotation on any class, it won't work. But I don't use such annotation. (However I have spring-webmvc on my classpath.)
When I start the application (in Tomcat), I got these log messages:
2017-04-23 16:54:55 DEBUG JndiTemplate:150 - Looking up JNDI object with name [java:comp/env/spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS]
2017-04-23 16:54:55 DEBUG JndiLocatorDelegate:101 - Converted JNDI name [java:comp/env/spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS] not found - trying original name [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS]. javax.naming.NameNotFoundException: Name [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS] is not bound in this Context. Unable to find [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS].
2017-04-23 16:54:55 DEBUG JndiTemplate:150 - Looking up JNDI object with name [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS]
2017-04-23 16:54:55 DEBUG JndiPropertySource:99 - JNDI lookup for name [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS] threw NamingException with message: Name [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS] is not bound in this Context. Unable to find [spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS].. Returning null.
2017-04-23 16:54:55 DEBUG PropertySourcesPropertyResolver:151 - Found key 'spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS' in [URL [file:C:/Program Files/Apache Software Foundation/Tomcat 9.0/conf/Catalina/localhost/Blowfish/config/application.properties]] with type [String]
Only one thing worked with both java.util.Date and joda.time:
#Configuration
public class AppConfig extends WebMvcConfigurerAdapter{
#Override
public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
for (HttpMessageConverter<?> converter : converters) {
if (converter instanceof MappingJackson2HttpMessageConverter) {
MappingJackson2HttpMessageConverter jsonMessageConverter = (MappingJackson2HttpMessageConverter) converter;
ObjectMapper objectMapper = jsonMessageConverter.getObjectMapper();
objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
break;
}
}
}
}
But I don't like this solution, it would be more elegant to use some configuriation in my application.properties.
I use Spring Boot 1.5.2.