On Wed, Oct 31, 2018 at 12:25 PM Rick Ley <[email protected]> wrote: > > Thank you for your response. Given that information, we are investigating the > possibility of writing a custom deserializer for this type. To get me > started, it looks like we should be extending StdDeserializer<Item>? Is that > correct?
Yes. Writing custom deserializers may be tricky with XML, but that is the useful base class here. -+ Tatu +- > > On Tuesday, October 30, 2018 at 8:04:45 PM UTC-7, Tatu Saloranta wrote: >> >> On Tue, Oct 30, 2018 at 7:26 PM Rick Ley <[email protected]> wrote: >> > >> > Hello! >> > >> > We are working on client libraries for a service. One of the service APIs >> > can return an xml list with heterogeneous types ordered by name. There are >> > two possible types in this list. A sample response might be: >> > >> > <Items> >> > <TypeA> >> > <Name1> >> > </TypeA> >> > <TypeB> >> > <Name2> >> > </TypeB> >> > <TypeA> >> > <Name3> >> > </TypeA> >> > <TypeA> >> > <Name4> >> > </TypeA> >> > <TypeB> >> > <Name5> >> > </TypeB> >> > <TypeB> >> > <Name6> >> > </TypeB> >> > <TypeA> >> > <Name7> >> > </TypeA> >> > <TypeB> >> > <Name8> >> > </TypeB> >> > <TypeB> >> > <Name9> >> > </TypeB> >> > </Item> >> > >> > The goal is to deserialize this list into two separate lists that each >> > hold all of one of the types. So with the given example, we would hope to >> > see (with the Name here being shorthand for a fully deserialized object): >> > listOfTypeA={Name1, Name3, Name4, Name7} and listOfTypeB = {Name2, Name5, >> > Name6, Name8, Name9}. Instead, we are seeing listOfTypeA = {Name7} and >> > listOfTypeB={Name8, Name9}. In other words, only the last contiguous set >> > of names is persisted and returned. >> > >> > I have stepped through the code and confirmed that this is because each >> > time an element of a certain type is encountered, a new list is created >> > and eventually overwrites any other list that was previously on the root >> > object rather than appending to an existing list. More specifically, each >> > time CollectionDeserializer.deserialize is called, a new list is >> > instantiated. >> > >> > Our object model is the parent type of name Item, which has an >> > ArrayList<TypeA> and ArrayList<TypeB>. Each is annoted with >> > @JsonProperty() and the respective type name. We are using Jackson version >> > 2.8.11. >> > >> > Is there a way we can configure Jackson to yield the behavior we want? Or >> > some sort of workaround you can suggest? Or should I make a feature >> > request/issue on the repo? >> > >> > Thank you for your help! >> >> To give a simple answer, no, Jackson can not be configured to do that. >> I also do not see this as something that would be possible to support >> in suggested form. >> >> Problem is two-fold: >> >> 1. Polymorphic type handling: it might be possible to make work, but >> lack of wrapping for list would present a problem. >> 2. Splitting of contents of one logical container at data format level >> into 2 Java Collections: this is not supported for any format. >> >> If (1) was resolved (that is, you could get one List populated, from >> polymorphic types), (2) could probably be handled by defining setter >> method that takes list, and then splitting that up in code. >> >> -+ Tatu +- > > -- > You received this message because you are subscribed to the Google Groups > "jackson-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "jackson-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. For more options, visit https://groups.google.com/d/optout.
