Deserializing Generic Type with GSON

Question

I've already seen this question:

but my use case is different, what I need is just convert json to T, and not List<T> or similar.. Here is what i need in code:

 val type: Type = object : TypeToken<T>() {}.type

and then

Gson().fromJson<T>(json, type)

But it's not working. It returns LinkedHashMap or something like that, but not the class represented by T. When I replace T with actual class type, it works, but with T it's not working. Could someone give me some advice ? Thanks

score 2 · Accepted Answer · answered Apr 12 '19 at 11:43

2

Just use Gson().fromJson(json, T.class); no TypeToken needed

answered Apr 12 '19 at 11:43

Starmixcraft

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1
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thanks for your answer, it lead me to the solution, which is in answer I posted... – Palejandro Apr 12 '19 at 11:58
that didn't work for me, no type in kotlin has .class! – fire in the hole Feb 08 '21 at 10:26

score 2 · Answer 2 · answered Apr 12 '19 at 11:57

I've found solution: Using just T::class.java was not enough, It gave me compilation error:

Cannot use T as reified type parameter. Use class instead

So I had to find solution how to fix it. What I had to do was change name of the function from this:

fun <T> myFunction

to this:

inline fun <reified T> myFunction

after that, no compilation error is shown, and code works more info about this topic is here : Instantiating generic array in Kotlin

and the deserialization looks like this:

 Gson().fromJson(json, T::class.java)

Deserializing Generic Type with GSON

2 Answers2