Gson Map<String, Any> to Object

Question

What's the most efficient way to convert a JSON in the format of Map<String, Any> to the corresponding java/kotlin object?

For now I have to use it like that which seems like a stupid implementation.

gson.fromJson(gson.toJson(mapToConvert), typeToken)

Any suggestions?

Answer 1

You can use a JsonElement:

val jsonElement = gson.toJsonTree(map)
val foo = gson.fromJson(jsonElement, Foo::class.java)

You can make this look nicer with a utility function:

inline fun <reified T : Any> Gson.fromMap(map: Map<*, *>) {
    return fromJson(toJsonTree(map), T::class.java)
}

Then you can call it like this:

gson.fromMap<Foo>(map)