Introduce @Mapper(maxDepth = 2)

[stankay]

Use case

When mapping JPA entities that contain bi-directional relations into DTOs, the mapper gets stuck in StackOverflow error for obvious reason. One must manually handle those mappings using available means, such as @Mapper(uses = ...) and @Mapping(qualifiedByName = ...), but in certain scenarios, it's a significant amount of work.

Generated Code

My suggestion is to introduce new method Integer maxDepth() into the @Mapper annotation, which would stop the recursive generation of mapping code after N recursions. This is sufficient to transfer entity and entities contained @manytoone, @OneToMany, @manytomany relations but not deeper.

Possible workarounds

No response

MapStruct Version

No response

[filiphr]

I am not sure that this is something that we can do. How would this work when you have separate mappers for the parent and child?

In my opinion this is something that should be fixed on the defining mapper side. You can define a custom mapping method that can then be used to ignore the second level of the mapping.