code: private boolean releaseIdUpdated(ReleaseId oldReleaseId, ReleaseId newReleaseId) {
          if (oldReleaseId == null && newReleaseId == null) {
              return false;
          }
          if (oldReleaseId == null && newReleaseId != null) {
              return true;
          }
          // now both releaseIds are non-null, so it is safe to call equals()
          return !oldReleaseId.equals(newReleaseId);
      }
docs: Checks whether the releaseId was updated (i.e. the old one is different from the new one).
  
  @param oldReleaseId old ReleaseId
  @param newReleaseId new releaseId
  @return true if the second (new) releaseId is different and thus was updated; otherwise false