hi! how do I achieve this? ```val courses: Collection<Course> = gson.fromJson(response.string(...

# getting-started

[César]

hi! how do I achieve this?

val courses: Collection<Course> = gson.fromJson(response.string(), Collection<Course>::class.java)

(the Collection<Course>::class.java part)

[César]

I was able to do it with

val listOfMyClassObject: Type = object : TypeToken<Collection<Course>>() {}.type
        val courses: Collection<Course> = gson.fromJson(response.string(), listOfMyClassObject)

but TypeToken is a class from Gson so I'm still curious how it can be done without that

[Paul Griffith]

inline fun <reified T> Gson.fromJson(json: String): T {
    return fromJson(json, T::class.java)
}

would be, in use, gson.fromJson<Collection<Course>>(response.string())
also, obligatory: don’t use GSON 🙂

[César]

what do you recommend instead?

[Paul Griffith]

The general recommendations are Moshi or Kotlin serialization I think
GSON isn’t aware of Kotlin’s nullability, so you can deserialize something into an invalid state
I’ve been able to use kotlinx-serialization but because it’s compile-time generation of code (to be multiplatform) it makes some tradeoffs that can make it more awkward to use for certain things

[César]

thanks for the inputs. I remember using Moshi, I'll take a look at that tomorrow

[Klitos Kyriacou]

You might also check if you're already pulling in a JSON library; for example, if you're using Spring, you might already have jackson-databind in your classpath, and Jackson has a Kotlin module too.