open static fun <T : Any> requiredSingleResult(@Nullable results: MutableCollection<T>): T
Return a single result object from the given Collection.
Throws an exception if 0 or more than 1 element found.
results - the result Collection (can be null but is not expected to contain null elements)
IncorrectResultSizeDataAccessException - if more than one element has been found in the given Collection
EmptyResultDataAccessException - if no element at all has been found in the given Collection
Return
the single result object