code: @Nonnull
    @Nonempty
    @OverrideOnDemand
    protected String getLogMessage (@Nullable final Throwable t)
    {
      if (t == null)
        return "An error occurred";
      return "An exception was thrown";
    }
docs: Get the text to be logged for a certain exception
  
  @param t
  The exception to be logged. May theoretically be <code>null</code>.
  @return The text to be logged. May neither be <code>null</code> nor empty.