Mapstruct: a particular case of shared mappings

In one mapper, I have this method

@Mapping(target = "n", source = "nome")
@Mapping(target = "c", source = "cognome")
@Mapping(target = "s", source = "sesso")
@Mapping(target = "CF", source = "codiceFiscaleOPartitaIva")
@Mapping(target = "co", source = "luogoNascita")
@Mapping(target = "p", source = "provinciaNascita")
@Mapping(target = "na", source = "nazioneNascita") // temporaneo
@Mapping(target = "d", source = "dataNascita", qualifiedByName = "XMLGregorianCalendarConvert")
@Mapping(target = "RSD", source = "denominazione")
@Mapping(target = "FN", source = "forzaNome")
@Mapping(target = "FC", source = "forzaCodiceFiscale")
@Mapping(target = "FCo", source = "forzaComune")
@Mapping(target = "NR", source = "numeroRea")
@Mapping(target = "PC", source = "provinciaCCIAA")
com.***.cmp.cgw.model.reportpersona.CAURequest.DI toDI(DittaIndividualeDTO source)

In another mapper, I have this method

@Mapping(target = "n", source = "nome")
@Mapping(target = "c", source = "cognome")
@Mapping(target = "s", source = "sesso")
@Mapping(target = "CF", source = "codiceFiscaleOPartitaIva")
@Mapping(target = "co", source = "luogoNascita")
@Mapping(target = "p", source = "provinciaNascita")
@Mapping(target = "na", source = "nazioneNascita") // temporaneo
@Mapping(target = "d", source = "dataNascita", qualifiedByName = "XMLGregorianCalendarConvert")
@Mapping(target = "RSD", source = "denominazione")
@Mapping(target = "FN", source = "forzaNome")
@Mapping(target = "FC", source = "forzaCodiceFiscale")
@Mapping(target = "FCo", source = "forzaComune")
@Mapping(target = "NR", source = "numeroRea")
@Mapping(target = "PC", source = "provinciaCCIAA")
com.***.cmp.cgw.model.reportimpresa.CAURequest.DI toDI(DittaIndividualeDTO source);

The mapping configurations are exactly the same, as you see
The two "DI" classes are in fact identical, but auto-generated in differente packages, and I am forced to use both of them
The source is identical in both methods
I cannot create a superclass or interface to be inherithed from the two DI classes

In this situation, how can I use only one configuration of mappings, to be shared between the two cases?

Solution

You can create an annotation that you annotate with these annotations. Then you annotate your methods with that new annotation.

For instance:

@Retention(RetentionPolicy.CLASS)
@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
@Mapping(target = "n", source = "nome")
@Mapping(target = "c", source = "cognome")
@Mapping(target = "s", source = "sesso")
@Mapping(target = "CF", source = "codiceFiscaleOPartitaIva")
@Mapping(target = "co", source = "luogoNascita")
@Mapping(target = "p", source = "provinciaNascita")
@Mapping(target = "na", source = "nazioneNascita") // temporaneo
@Mapping(target = "d", source = "dataNascita", qualifiedByName = "XMLGregorianCalendarConvert")
@Mapping(target = "RSD", source = "denominazione")
@Mapping(target = "FN", source = "forzaNome")
@Mapping(target = "FC", source = "forzaCodiceFiscale")
@Mapping(target = "FCo", source = "forzaComune")
@Mapping(target = "NR", source = "numeroRea")
@Mapping(target = "PC", source = "provinciaCCIAA")
@interface DittaIndividualeDTOMappings {
}

@DittaIndividualeDTOMappings
com.***.cmp.cgw.model.reportpersona.CAURequest.DI toDI(DittaIndividualeDTO source)

@DittaIndividualeDTOMappings
com.***.cmp.cgw.model.reportimpresa.CAURequest.DI toDI(DittaIndividualeDTO source);

Note that your annotation needs the correct retention and target. I've used CLASS retention because it's not necessary to access the annotation at runtime; it's also what MapStruct uses itself. For the target I've used METHOD because only methods should get the mapping, and ANNOTATION_TYPE so you can use it in other annotations as well.