code: @Nonnull
    public static <T> JPAExecutionResult <T> createFailure (@Nullable final Exception ex)
    {
      return new JPAExecutionResult <> (ESuccess.FAILURE, null, ex);
    }
docs: Create a new failure object.
  
  @param ex
  The exception that occurred.
  @return Never <code>null</code>.
  @param <T>
  Data type - depends on callers requirements.