The problem is that mapstruct will attempt to map the S onto the T information, but it cannot determine what T or S is.

Perhaps the checking for generics can become less strict, when the fields affected by the generics are already explicitly specified. In your case it is most likely that inside PageInfo<T> exists a List<T> object.

The problem is that mapstruct will attempt to map the S onto the T information, but it cannot determine what T or S is.

Perhaps the checking for generics can become less strict, when the fields affected by the generics are already explicitly specified. In your case it is most likely that inside PageInfo<T> exists a List<T> object.

@Zegveld You are right, The List<T> exists. So, Can mapstruct support my demand?

It is currently not supported, but this is a nice enhancement to be added.

It is currently not supported, but this is a nice enhancement to be added.

I'll look forward to it.thinks

please do not close this issue, as it will be used to track this.

please do not close this issue, as it will be used to track this.

got

hi, @Zegveld
MapStruct seems to have to specify the specific class type of the JavaBean. Will this enhancement change this feature
Or this enhancement is only for JavaBean member variables, so that member variables can use generics, but JavaBean class still need to specific class, and generics cannot be used
Like this?Such conversion will become possible?

class JavaBean01<A> {
    A object1;
   ...
}

class JavaBean02<A>{
    A object1;
   ...
}

Such conversion is still impossible?
<S, T> T mapper(S s, Class<T> t)

Or will both of these situations become possible

@xg578962913 a generic conversion such as <S, T> T mapper(S s, Class<T> t) is not possible in MapStruct and we are not planning to implement something like that.

If you are interested in something like that then you could implement it in your own way by implementing a custom processor that is going to create an implementation that works for something like this.

@filiphr Thanks, I got it

@filiphr I have another use case which should be supported:

@Mapper
abstract class ServiceRequestMapper {
    @Mapping(target = ".", source = "request")
    fun <Request: IdlData<Request>> toRequest(serviceRequest: ServiceRequest<Request>) : Request = serviceRequest.request
}

The ServiceRequest class has a request attribute that is always of type Request.
I don't see why the constraints I provided do not provide enough type information for the automatic generation of the mapper.

@thedrow this looks like Kotlin code. How does the java code for this example look like?