why do you have an explicit `IntDeserializer()`? maybe try removing that line, gson can deserialize ...

# ktor

[Kevin Schmeichel]

why do you have an explicit IntDeserializer()? maybe try removing that line, gson can deserialize Ints automatically.

[tjohnn]

It doesn't deserialize empty string for me, eg sending ageGroupId:"" gives me NumberFormatException: empty String which I wanted to handle explicitly. Is there a way to handle that without adapter

[tjohnn]

Adapter is not resolving the issue for me either

[Kevin Schmeichel]

you can't catch the exception in your adaptor?

[Kevin Schmeichel]

like this:

[Kevin Schmeichel]

https://stackoverflow.com/questions/8863429/how-to-handle-a-numberformatexception-with-gson-in-deserialization-a-json-respon?rq=1

[tjohnn]

Yes I am doing something like that but the adapter doesn’t seem to be called, so it’s still using the default deserializer

[Kevin Schmeichel]

ok, so you just need to figure out how to properly register the adaptor. did you try registerTypeAdapterFactory(...)?

[Kevin Schmeichel]

or at the bottom of the stackoverflow, maybe you need something like:

[Kevin Schmeichel]

registerTypeAdapter(java.lang.Integer::class.java, adapter)

[tjohnn]

Yes I am doing it like this:

install(ContentNegotiation){
                register(ContentType.Application.Json, GsonConverter(GsonBuilder().apply {
                    setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)

                    registerTypeAdapter(DateTime::class.java, DateTimeDeserializer())
                    registerTypeAdapter(Int::class.java, IntDeserializer())
                }.create()))
            }

[Kevin Schmeichel]

maybe you need java.lang.Integer::class.java instead?

[tjohnn]

Hmm.. I’d try that. Thanks

[Kevin Schmeichel]

or try the Factory method like in the stackoverflow?

[tjohnn]

java.lang.Integer::class.java works fine thanks

[tjohnn]

Is that because gson doesn't recognize kotlin Int or what?

[Kevin Schmeichel]

yeah, that's my guess