How To Fetch DTO Via A Custom ResultTransformer
Description: Fetching more read-only data than needed is prone to performance penalties. Using DTO allows us to extract only the needed data. Sometimes, we need to fetch a DTO made of a subset of properties (columns) from a parent-child association. For such cases, we can use SQL JOIN that can pick up the desired columns from the involved tables. But, JOIN returns an List<Object[]> and most probably you will need to represent it as a List<ParentDto>, where a ParentDto instance has a List<ChildDto>. For such cases, we can rely on a custom Hibernate ResultTransformer. This application is a sample of writing a custom ResultTransformer.
Key points:
- implement the
ResultTransformerinterface
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