Optional types not deserializable?

[vic-cw]

I might be missing something here, but I am under the impression that RESTClient.factory(SomeResourceWhichReturnsAnOptional) throws an exception.

Caused by: java.lang.NullPointerException
at org.teavm.flavour.json.emit.JsonDeserializerEmitter.emitIdCheck(JsonDeserializerEmitter.java:222)
at org.teavm.flavour.json.emit.JsonDeserializerEmitter.lambda$emitClassDeserializer$20(JsonDeserializerEmitter.java:183)
at org.teavm.metaprogramming.impl.MetaprogrammingImpl.proxy(MetaprogrammingImpl.java:300)
at org.teavm.metaprogramming.impl.MetaprogrammingImpl.proxy(MetaprogrammingImpl.java:238)
at org.teavm.flavour.json.emit.JsonDeserializerEmitter.emitClassDeserializer(JsonDeserializerEmitter.java:172)
at org.teavm.flavour.json.emit.JsonDeserializerEmitter.getClassDeserializer(JsonDeserializerEmitter.java:111)
at org.teavm.flavour.json.JSON.getClassDeserializer(JSON.java:79)

This might be due to the fact that the object mapper has to be configured with the Jdk8 module.

Is that the case?

[vic-cw]

I guess that is the case, since I get the same exception for LocalDate

[ScraM-Team]

JSON deserialization definitely has some restrictions. Start with primitives, Strings, and Enums (and contained classes containing those types). Be sure to return a value for every field -- nulls tend to cause problems.

The examples are very helpful to see what is possible.

Please post here if you get it working or not.

[ScraM-Team]

Oh, are you using the latest bintray builds or the older 0.1.0 build from maven central?

[vic-cw]

@ScraM-Team thanks for the answer!

Yes I am using 0.1.0 from Maven Central.

I played around, and indeed with different data types things were fine, until I re-introduced either Optional or LocalDate

[ScraM-Team]

The 0.1.0 build is over a year old, you should definitely consider trying the bintray release: https://bintray.com/konsoletyper/teavm/teavm-flavour-dev/0.2.0-dev-52

https://bintray.com/konsoletyper/teavm/teavm-flavour-dev/0.2.0-dev-52

[vic-cw]

Ok thanks, I'll try.

Do you know if support for these types has been added since?

[ScraM-Team]

Sorry, I'm not sure what types were added.

I'm going to start a thread in the forums for Flavour enhancements and feedback on what is trickiest when starting out.

[konsoletyper]

Optional types are not supported by Flavour serialization

[vic-cw]

@konsoletyper thanks!