Apache SIS was used to try to open the SpatialMetadata database (which contains the EPSG dataset) using the Derby driver on the classpath, or if no such driver is found using the JavaDB driver embedded in the JDK from Java 6 to Java 8. But JavaDB has been removed from the JDK in Java 9. We nevertheless kept the code looking for JavaDB because SIS was still compatible with Java 8. But even JDK 8 removed JavaDB since update 181 (JDK 8u181). That update expired one year and half ago, in October 16, 2018 (was released in July 17, 2018). Consequently there is no longer any reason to keep the code looking for JavaDB.
- Reference: Update 181 release note