Can I force mapstruct to delegate a mapping method to another mapping method or a default (builtin) conversion? - mapstruct

Question

Can I force mapstruct to delegate a mapping method to another mapping method or a default (builtin) conversion?
I basically would like to access a custom mapping method of a uses MapperA inside the custom mapping method of the using MapperX. But I can't get a hold of the injected MapperA inside the custom mapping method of MapperX.
The same is true for builtin conversions. I want to make use of a builtin conversion of mapstruct inside a custom method. Like convert from Date to ZonedDateTime.
e.g.:
#Mapper(componentModel="cdi")
public interface MapperA {
A fromB(B b);
default Q fromR(R r) {
Q q = ..<do some stuff with r>..
return q;
}
}
#Mapper(componentModel="cdi"
uses = MapperA.class
)
public interface MapperX {
default X custom(Y y) {
Date someJavaUtilDate = customDateFromY(y);
//I dont want to code Date->ZonedDateTime myself
//I want mapstruct to do its builtin conversion, so call placeholder:
X.myZonedDateTime = builtinConversionPlaceholder(someJavaUtilDate)
R r = ..<do some stuff with y>..
X.q = usesMapperPlaceholder(r); // injected "uses MapperA" is not directly accessible here?
}
#org.mapstruct.Find_Me_A_Matching_Method_Builtin_Or_In_Uses_Mapper
// will not map properties of Date to ZonedDateTime
// but will use mapstruct builtin conversion code
ZonedDateTime builtinConversionPlaceholder(java.util.Date date);
#org.mapstruct.Find_Me_A_Matching_Method_Builtin_Or_In_Uses_Mapper
// will delegate to MapperA.fromR
Q usesMapperPlaceholder(R r);
}

Answer 1

No it is not possible to force MapStruct to use. build in conversion method.
What you can do is to create some wrapper objects that will be mapped between java.util.Date and ZonedDateTime, MapStruct will then map those using the built in mappings.
e.g.
#Mapper(componentModel="cdi")
public interface MapperA {
A fromB(B b);
default Q fromR(R r) {
Q q = ..<do some stuff with r>..
return q;
}
}
#Mapper(componentModel="cdi"
uses = MapperA.class
)
public abstract class MapperX {
#Inject
MapperA mapperA;
default X custom(Y y) {
Date someJavaUtilDate = customDateFromY(y);
X.myZonedDateTime = toZonedDateTime(someJavaUtilDate).getValue();
R r = ..<do some stuff with y>..
X.q = mapperA.fromR(r);
}
Wrapper<ZonedDateTime> toZonedDateTime(Wrapper<java.util.Date> date);
static class Wrapper<T> {
private T value;
//getters and setters
}
}