How to map java collection to its size

Question

I would like to know how I can map for example List to its size? I have some SourseClass.class containing List of something and I would like to map this List only to its size so DtoClass.class would contain "List.size()"

Answer 1

You can use expression for that, here is example:

@Mapping(target = "list", expression = "java(sourceClass.getList()!= null ? sourceClass.getList().size():0)")
DtoClass toDto(SourceClass sourceClass);