EDIT

This intended function of FieldUnitDTO OccurrenceServiceImpl.findFieldUnitDTO(DerivateDTO derivedUnitDTO, Collection<FieldUnitDTO> fieldUnits, HashMap<UUID, DerivateDTO> alreadyCollectedSpecimen) is quite unclear, not only because the documentation is missing (#8458), but also since the method is confuses reagarding the method signature: All detected fieldunits are added to the Collection<FieldUnitDTO> fieldUnits passed as parameter but one of the field units is returned. From the description of #8423 supports the impression that this method covers two distinct functionalities at the same.

TODO:

• refactor the method to make its clarify its purpose and concerns. - DONE
• revise commented code and clean up
• remove the init strategy (first FIXME in code) - DONE
• allow for walking multiple origin paths (second FIXME in code) ---> #9430
• The methods OccurrenceServiceImpl._findFieldUnitDTO and OccurrenceServiceImpl.findFieldUnitDTO() are operating on DTOs. This causes a computation overhead which could be significant in cases where intermediate derivation events exists. The creation of the DTOs is quite expensive since they are relatively complex objects for which quite some entity initialization is necessary. It would be better to do the search for field units purely on the entity level and to create DTOs in a final step only for those entities which are needed for the out put or response. ---> #9431