Date/Time Java <=> JavaScript

application.properties

# You can configure the date format and timezone used by Spring which uses in the background Jackson2.
#
# Normally, you do not have to change nothing in the JavaScript code that run on the browsers around the world.
# It will use JSON.stringify() to serialize the date which will be sent in the UTC timezone to the server (Java on backend).
# Example: 2018-11-29T14:03:27.281Z
#
# However, if you are having problems, try to set the values below in your application.properties file for the Spring application.
#
# Visit the Spring documentation for more information:
# https://docs.spring.io/spring-boot/docs/current/reference/html/common-application-properties.html
#
# JACKSON (JacksonProperties)
spring.jackson.time-zone: UTC
# That property is only used for the java.util.Date
# according to https://stackoverflow.com/questions/43622259/how-to-use-spring-boots-spring-jackson-date-format-property
spring.jackson.date-format=yyyy-MM-dd'T'HH:mm:ss.SSSXXX

datetime.js

let myDate = new Date();
JSON.stringify(myDate);
// produces for example:
// 2018-12-07T20:41:03.345Z

MyDatetime.java

// It works only using Java SDK 8+
class MyDatetime {
  
  /**
   * Convert a date as string generated by JavaScript using the command JSON.stringify()
   * to a Java Date.
   *
   * @param sDate date to be converted. Ex:  2018-11-29T14:03:27.281Z
   * @return Java Date
   */
  Date convertJavaScriptDate(String sDate) {
    ZonedDateTime zdt = ZonedDateTime.parse(sDate, DateTimeFormatter.ISO_OFFSET_DATE_TIME);
    Date date = Date.from(zdt.toInstant());
    return date;
  }
}