Set default timezone of jax-rs jackson provider for deserialization of timestamp to XmlGregorianCalendar JAXB date field.

JacksonConfigurator.java

package de.kommone.kmc.api;

import java.util.TimeZone;

import javax.ws.rs.Produces;
import javax.ws.rs.ext.ContextResolver;
import javax.ws.rs.ext.Provider;

import com.fasterxml.jackson.databind.ObjectMapper;

@Provider
@Produces("application/json")
public class JacksonConfigurator implements ContextResolver<ObjectMapper> {

    private ObjectMapper mapper = new ObjectMapper();

    public JacksonConfigurator() {
        mapper.setTimeZone(TimeZone.getTimeZone("Europe/Berlin"));
    }

    @Override
    public ObjectMapper getContext(Class<?> arg0) {
        return mapper;
    }

}

pom.xml

...
<dependency>
  <groupId>org.glassfish.jersey.containers</groupId>
  <artifactId>jersey-container-servlet</artifactId>
  <version>2.25.1</version>
  <exclusions>
    <exclusion>
      <groupId>org.glassfish.jersey.media</groupId>
      <artifactId>jersey-media-jaxb</artifactId>
    </exclusion>
  </exclusions>
</dependency>
<dependency>
  <groupId>org.glassfish.jersey.media</groupId>
  <artifactId>jersey-media-json-jackson</artifactId>
  <version>2.25.1</version>
</dependency>
...

web.xml

  <servlet>
    <servlet-name>javax.ws.rs.core.Application</servlet-name>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>javax.ws.rs.core.Application</servlet-name>
    <url-pattern>/api/*</url-pattern>
  </servlet-mapping>

Perhaps it is a classloading issue, at least that was what I was facing. I was using Payara5 which already provides Jackson libraries and my war contained them as well. Removing them from my war resolved it.