Saving retrofit response Model to shared preferences. Using Generics

DemoData.kt

data class DemoData(
    val email: String,
    val name: String,
    val username: String
)


// Usage For getting saved data.
 var userData = getModelPref(getPreferences, localUserData, DemoData::class.java)

// Usage for Saving Model
var demo = DemoData("[email protected]", "John", "John123")
var userData = setModelPref(getPreferences, localUserData, demo::class.java)

Utils.kt

// Get saved Model class
fun <T> getModelPref(sharedPreferences: SharedPreferences, name: String, model: Class<T>) : T {
    val value = sharedPreferences.getString(name, "")
    return Gson().fromJson(value, model) as T
}

// Saving Model class
fun setModelPref(sharedPreferences: SharedPreferences, name: String, model: Any) {
    val prefsEditor: SharedPreferences.Editor = sharedPreferences.edit()
    val gson = Gson().toJson(model)
    prefsEditor.putString(name, gson).apply()
}

For anyone who needs the java version, everything is similar but cast your model/class object to Type:

return Gson().fromJson(value, model) as T

to

import java.lang.reflect.Type; // import this in your current class

Gson gson = new Gson();
return gson.fromJson(value, (Type) DemoData.class);