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zsmb.co
zsmb13
A Kotlin library design case study
ft
Krate Moshi
Márton Braun
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Krate
AutSoft/Krate
Moshi
square/moshi
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Krate
AutSoft/Krate
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Krate
interface Krate {
val sharedPreferences: SharedPreferences
}
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Krate
interface Krate {
val sharedPreferences: SharedPreferences
}
abstract class SimpleKrate(context: Context) : Krate {
override val sharedPreferences =
PreferenceManager.getDefaultSharedPreferences(context)
}
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interface Krate {
val sharedPreferences: SharedPreferences
}
Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var onboarded by booleanPref("onboarded")
var appOpenCount by intPref("appOpenCount")
var username by stringPref("username")
}
abstract class SimpleKrate(context: Context) : Krate {
override val sharedPreferences =
PreferenceManager.getDefaultSharedPreferences(context)
}
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interface Krate {
val sharedPreferences: SharedPreferences
}
Krate
myKrate.onboarded = true
myKrate.appOpenCount++
myKrate.username = "t1gg3r"
class MyKrate(context: Context) : SimpleKrate(context) {
var onboarded by booleanPref("onboarded")
var appOpenCount by intPref("appOpenCount")
var username by stringPref("username")
}
abstract class SimpleKrate(context: Context) : Krate {
override val sharedPreferences =
PreferenceManager.getDefaultSharedPreferences(context)
}
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Krate
myKrate.onboarded = true
myKrate.appOpenCount++
myKrate.username = "t1gg3r"
var onboarded by booleanPref("onboarded")
var username by stringPref("username")
abstract class SimpleKrate(context: Context) : Krate {
override val sharedPreferences =
PreferenceManager.getDefaultSharedPreferences(context)
}
}
var appOpenCount by intPref("appOpenCount")
class MyKrate(context: Context) : SimpleKrate(context) {
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by intPref("appOpenCount")
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
class IntDelegate(private val key: String)
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
class IntDelegate(private val key: String) : ReadWriteProperty {
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
}
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
}
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount: Int by IntDelegate("appOpenCount")
}
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
}
}
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Krate
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
}
}
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
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Krate
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
return thisRef.sharedPreferences.getInt(key, 0)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
thisRef.sharedPreferences.edit().putInt(key, value).apply()
}
}
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by IntDelegate("appOpenCount")
}
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
return thisRef.sharedPreferences.getInt(key, 0)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
thisRef.sharedPreferences.edit().putInt(key, value).apply()
}
}
fun Krate.intPref(key: String): ReadWriteProperty {
return IntDelegate(key)
}
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Krate
class MyKrate(context: Context) : SimpleKrate(context) {
var appOpenCount by intPref("appOpenCount")
}
class IntDelegate(private val key: String) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Int {
return thisRef.sharedPreferences.getInt(key, 0)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Int) {
thisRef.sharedPreferences.edit().putInt(key, value).apply()
}
}
fun Krate.intPref(key: String): ReadWriteProperty {
return IntDelegate(key)
}
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Krate
AutSoft/Krate
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Moshi
square/moshi
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Moshi
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Moshi
› Gson v3 in everything but name
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
Okio
Retrofit
OkHttp
Moshi
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
Okio
Retrofit
OkHttp
Moshi
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String,
)
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String,
)
val moshi = Moshi.Builder().build()
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String,
)
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String,
)
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String,
)
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
Exception in thread "main"
com.squareup.moshi.JsonDataException:
Required value 'description' missing at $
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String?,
)
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String
)
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
Burger(name=Cheeseburger, description=null)
?,
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String
)
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
› Default parameter values
?,
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String
)
,
= "Yummy!"
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
val moshi = Moshi.Builder().build()
val burgerAdapter =
moshi.adapter(Burger::class.java)
val burger = burgerAdapter.fromJson(
"{\"name\": \"Cheeseburger\"}"
)
Burger(name=Cheeseburger, description=Yummy!)
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String
)
,
= "Yummy!"
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Codegen, reflection, or both
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String = "Yummy!",
)
val moshi = Moshi.Builder().build()
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Codegen, reflection, or both
data class Burger(
val name: String,
val description: String = "Yummy!",
)
val moshi = Moshi.Builder().build()
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Codegen, reflection, or both
data class Burger(
val name: String,
val description: String = "Yummy!",
)
val moshi = Moshi.Builder()
.add(KotlinJsonAdapterFactory())
.build()
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Codegen, reflection, or both
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String = "Yummy!",
)
val moshi = Moshi.Builder()
.add(KotlinJsonAdapterFactory())
.build()
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Codegen, reflection, or both
› Always calls constructors
@JsonClass(generateAdapter = true)
data class Burger(
val name: String,
val description: String = "Yummy!",
) {
init {
println("$name coming up...")
}
}
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Always calls constructors
› Named after Jake’s dog
› Codegen, reflection, or both
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Moshi
› Gson v3 in everything but name
› Part of the Ok libraries
› Streaming API
› Nullable values
› Default parameter values
› Always calls constructors
› Named after Jake’s dog
› Codegen, reflection, or both
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Storing complex data
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DISCLAIMER
Consider using a database before storing
data like this in SharedPreferences
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Gson delegate
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Gson delegate
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
java.lang.ClassCastException:
com.google.gson.internal.LinkedTreeMap
cannot be cast to
hu.autsoft.krate.gson.TestModel
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): Object? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: Object?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key)
}
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Object
T
Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
inline fun ?> {
return GsonDelegate(key)
}
Krate.gsonPref(key: String): ReadWriteProperty
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inline fun ?> {
return GsonDelegate(key)
}
Object
T
Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
Krate.gsonPref(key: String): ReadWriteProperty
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Gson delegate
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, object : TypeToken() {}.type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
inline fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key, object : TypeToken() {}.type)
}
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inline fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key, object : TypeToken() {}.type)
}
Gson delegate
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
class GsonDelegate(
private val key: String,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, )
private val type: Type,
type
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Testing Krate
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Gson delegate tests
data class TestModel(val x: Int, val y: Double, val z: String)
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Gson delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
data class TestModel(val x: Int, val y: Double, val z: String)
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Gson delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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Gson delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
@Test
fun testSimpleValue() {
val model = TestModel(x = 42, y = 3.141592, z = "shibboleth")
krate.simpleValue = model
assertEquals(model, krate.simpleValue)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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Gson delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
@Test
fun testSimpleValue() {
val model = TestModel(x = 42, y = 3.141592, z = "shibboleth")
krate.simpleValue = model
assertEquals(model, krate.simpleValue)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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Gson delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
@Test
fun testListOfValues() {
val list = listOf(
TestModel(x = 42, y = 3.141592, z = "shibboleth"),
TestModel(x = 13, y = 6.283185, z = "signal"),
)
krate.listOfValues = list
assertEquals(list, krate.listOfValues)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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Gson delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
@Test
fun testListOfValues() {
val list = listOf(
TestModel(x = 42, y = 3.141592, z = "shibboleth"),
TestModel(x = 13, y = 6.283185, z = "signal"),
)
krate.listOfValues = list
assertEquals(list, krate.listOfValues)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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ft
Krate Moshi
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class GsonDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val gson = Gson()
val string = thisRef.sharedPreferences.getString(key, null)
return gson.fromJson(string, type)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
inline fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key, object : TypeToken() {}.type)
}
Moshi delegate
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inline fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key, object : TypeToken() {}.type)
}
Moshi delegate
gson Gson()
=
.fromJson(string )
, type
gson
class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val
val string = thisRef.sharedPreferences.getString(key, null)
return
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
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inline fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key, object : TypeToken() {}.type)
}
Moshi delegate
moshi.adapter(type)
=
adapter
.fromJson(string)
adapter
class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val
val string = thisRef.sharedPreferences.getString(key, null)
return
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val gson = Gson()
thisRef.sharedPreferences.edit()
.putString(key, gson.toJson(value))
.apply()
}
}
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class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val adapter = moshi.adapter(type)
val string = thisRef.sharedPreferences.getString(key, null)
return adapter.fromJson(string)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val adapter = moshi.adapter(type)
thisRef.sharedPreferences.edit()
.putString(key, adapter.toJson(value))
.apply()
}
}
inline fun Krate.gsonPref(key: String): ReadWriteProperty {
return GsonDelegate(key, object : TypeToken() {}.type)
}
Moshi delegate
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class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val adapter = moshi.adapter(type)
val string = thisRef.sharedPreferences.getString(key, null)
return adapter.fromJson(string)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val adapter = moshi.adapter(type)
thisRef.sharedPreferences.edit()
.putString(key, adapter.toJson(value))
.apply()
}
}
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, object : TypeToken() {}.type)
}
Moshi delegate
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class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val adapter = moshi.adapter(type)
val string = thisRef.sharedPreferences.getString(key, null)
return adapter.fromJson(string)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val adapter = moshi.adapter(type)
thisRef.sharedPreferences.edit()
.putString(key, adapter.toJson(value))
.apply()
}
}
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, object : TypeToken() {}.type)
}
Moshi delegate
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key,
}
class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
override operator fun getValue(thisRef: Krate, property: KProperty<*>): T? {
val adapter = moshi.adapter(type)
val string = thisRef.sharedPreferences.getString(key, null)
return adapter.fromJson(string)
}
override operator fun setValue(thisRef: Krate, property: KProperty<*>, value: T?) {
val adapter = moshi.adapter(type)
thisRef.sharedPreferences.edit()
.putString(key, adapter.toJson(value))
.apply()
}
}
Moshi delegate
???)
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Class
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java.lang.Class
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java.lang.Class
classes and interfaces in a running Java application
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java.lang.Class
classes and interfaces in a running Java application
Class c1 = object.getClass();
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java.lang.Class
classes and interfaces in a running Java application
Class c1 = object.getClass(); any.javaClass // Kotlin
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java.lang.Class
classes and interfaces in a running Java application
Class c1 = object.getClass();
Class c2 = String.class;
any.javaClass // Kotlin
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java.lang.Class
classes and interfaces in a running Java application
Class c1 = object.getClass();
Class c2 = String.class;
any.javaClass
"hello world".getClass(); // class java.lang.String
new ArrayList().getClass(); // class java.util.ArrayList
new Serializable() {}.getClass(); // class com.example.Main$1
// Kotlin
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java.lang.Class
classes and interfaces in a running Java application
Class c1 = object.getClass();
Class c2 = String.class;
any.javaClass
c.getName();
c.getSimpleName();
c.getCanonicalName();
c.getTypeName();
// Kotlin
[I
int[]
int[]
int[]
java.lang.String
String
java.lang.String
java.lang.String
com.example.Main$1
null
com.example.Main$1
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java.lang.Class
classes and interfaces in a running Java application
Class c1 = object.getClass();
Class c2 = String.class;
any.javaClass
c.getName();
c.getSimpleName();
c.getCanonicalName();
c.getTypeName();
Annotation[] annotations = c.getAnnotations();
Class[] interfaces = c.getInterfaces();
Constructor[] constructors = c.getConstructors();
Field[] fields = c.getFields();
Method[] methods = c.getMethods();
// Kotlin
[I
int[]
int[]
int[]
java.lang.String
String
java.lang.String
java.lang.String
com.example.Main$1
null
com.example.Main$1
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java.lang.reflect.Type
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java.lang.reflect.Type
all types in the Java programming language
- raw types
- parameterized types
- array types
- type variables
- primitive types
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java.lang.reflect.Type
all types in the Java programming language
- raw types
- parameterized types
- array types
- type variables
- primitive types
String getTypeName();
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java.lang.reflect.Type
all types in the Java programming language
- raw types
- parameterized types
- array types
- type variables
- primitive types
Class
String getTypeName();
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java.lang.reflect.Type
all types in the Java programming language
- raw types
- parameterized types
- array types
- type variables
- primitive types
Class ParameterizedType
Type getRawType();
Type[] getActualTypeArguments();
String getTypeName();
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Class Type
No generics Supports generics
Java reflection
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass
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kotlin.reflect.KClass
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kotlin.reflect.KClass
val k1: KClass<*> = any::class
val k2: KClass<*> = String::class
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kotlin.reflect.KClass
val simpleName: String?
val qualifiedName: String?
val members: Collection>
val constructors: Collection>
val nestedClasses: Collection>
val typeParameters: List
val supertypes: List
val sealedSubclasses: List>
val visibility: KVisibility?
val k1: KClass<*> = any::class
val k2: KClass<*> = String::class
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kotlin.reflect.KClass
val k1: KClass<*> = any::class
val k2: KClass<*> = String::class
val isFinal: Boolean
val isOpen: Boolean
val isAbstract: Boolean
val isSealed: Boolean
val isData: Boolean
val isInner: Boolean
val isCompanion: Boolean
val isFun: Boolean
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val c: Class<*> = String::class.java
kotlin.reflect.KClass
val k1: KClass<*> = any::class
val k2: KClass<*> = String::class
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val c: Class<*> = String::class.java
kotlin.reflect.
val k1: KClass<*> = any::class
val k2: KClass<*> = String::class
String.class // Java
// Kotlin
KClass
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass KType
ParameterizedType
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass KType
ParameterizedType
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass KType
rawType
actualTypeArguments
ParameterizedType
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Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass KType
rawType
actualTypeArguments
ParameterizedType
classifier
arguments
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rawType
actualTypeArguments
ParameterizedType
classifier
arguments
isMarkedNullable
Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass KType
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rawType
actualTypeArguments
ParameterizedType
classifier
arguments
Class Type
No generics Supports generics
Java reflection
Kotlin reflection
KClass KType
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Looking for a Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, ???)
}
class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
...
}
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Looking for a Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
...
}
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Looking for a Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
class MoshiDelegate(
private val key: String,
private val type: Type,
) : ReadWriteProperty {
...
}
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Moshi delegate tests
class GsonTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by gsonPref("simpleValue")
var listOfValues: List? by gsonPref("listOfValues")
}
@Test
fun testSimpleValue() {
val model = TestModel(x = 42, y = 3.141592, z = "shibboleth")
krate.simpleValue = model
assertEquals(model, krate.simpleValue)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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Moshi delegate tests
class MoshiTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by moshiPref("simpleValue")
var listOfValues: List? by moshiPref("listOfValues")
}
@Test
fun testSimpleValue() {
val model = TestModel(x = 42, y = 3.141592, z = "shibboleth")
krate.simpleValue = model
assertEquals(model, krate.simpleValue)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = GsonTestKrate(targetContext)
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Moshi delegate tests
class MoshiTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by moshiPref("simpleValue")
var listOfValues: List? by moshiPref("listOfValues")
}
@Test
fun testSimpleValue() {
val model = TestModel(x = 42, y = 3.141592, z = "shibboleth")
krate.simpleValue = model
assertEquals(model, krate.simpleValue)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = MoshiTestKrate(targetContext)
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Moshi delegate tests
class MoshiTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by moshiPref("simpleValue")
var listOfValues: List? by moshiPref("listOfValues")
}
@Test
fun testSimpleValue() {
val model = TestModel(x = 42, y = 3.141592, z = "shibboleth")
krate.simpleValue = model
assertEquals(model, krate.simpleValue)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = MoshiTestKrate(targetContext)
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Moshi delegate tests
class MoshiTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by moshiPref("simpleValue")
var listOfValues: List? by moshiPref("listOfValues")
}
@Test
fun testListOfValues() {
val list = listOf(
TestModel(x = 42, y = 3.141592, z = "shibboleth"),
TestModel(x = 13, y = 6.283185, z = "signal"),
)
krate.listOfValues = list
assertEquals(list, krate.listOfValues)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = MoshiTestKrate(targetContext)
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Moshi delegate tests
class MoshiTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by moshiPref("simpleValue")
var listOfValues: List? by moshiPref("listOfValues")
}
@Test
fun testListOfValues() {
val list = listOf(
TestModel(x = 42, y = 3.141592, z = "shibboleth"),
TestModel(x = 13, y = 6.283185, z = "signal"),
)
krate.listOfValues = list
assertEquals(list, krate.listOfValues)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = MoshiTestKrate(targetContext)
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class MoshiTestKrate(context: Context) : SimpleKrate(context) {
var simpleValue: TestModel? by moshiPref("simpleValue")
var listOfValues: List? by moshiPref("listOfValues")
}
@Test
fun testListOfValues() {
val list = listOf(
TestModel(x = 42, y = 3.141592, z = "shibboleth"),
TestModel(x = 13, y = 6.283185, z = "signal"),
)
krate.listOfValues = list
assertEquals(list, krate.listOfValues)
}
data class TestModel(val x: Int, val y: Double, val z: String)
val krate = MoshiTestKrate(targetContext)
Moshi delegate tests
java.lang.AssertionError:
Expected :[
TestModel(x=42, y=3.141592, z=shibboleth),
TestModel(x=13, y=6.283185, z=signal)
]
Actual :[
{x=42.0, y=3.141592, z=shibboleth},
{x=13.0, y=6.283185, z=signal}
]
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java.lang.AssertionError:
Expected :[
TestModel(x=42, y=3.141592, z=shibboleth),
TestModel(x=13, y=6.283185, z=signal)
]
Actual :[
{x=42.0, y=3.141592, z=shibboleth},
{x=13.0, y=6.283185, z=signal}
]
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Actual :[
{x=42.0, y=3.141592, z=shibboleth},
{x=13.0, y=6.283185, z=signal}
]
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Moshi delegate tests
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Moshi delegate tests
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Moshi delegate tests
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var simpleValue by moshiPref("simpleValue")
var listOfValues by moshiPref>("listOfValues")
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Moshi delegate tests
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var simpleValue by moshiPref("simpleValue")
var listOfValues by moshiPref>("listOfValues")
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
class hu.autsoft.krate.moshi.TestModel
Moshi delegate tests
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class hu.autsoft.krate.moshi.TestModel
interface java.util.List
var simpleValue by moshiPref("simpleValue")
var listOfValues by moshiPref>("listOfValues")
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Moshi delegate tests
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Looking for a Type
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Types.newParameterizedType(List::class.java, TestModel::class.java)
Looking for a Type
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, T::class.java)
}
Types.newParameterizedType(List::class.java, TestModel::class.java)
java.util.List
Looking for a Type
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inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(
key,
Types.newParameterizedType(T::class.java, ???::class.java)
)
}
Types.newParameterizedType(List::class.java, TestModel::class.java)
java.util.List
Looking for a Type
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Looking for a Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key,
}
)
???
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Looking for a Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, object : TypeToken() {}.type)
}
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TypeToken object : TypeToken() {}.type
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
getGenericSuperclass();
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getGenericSuperclass();
* ...
*/
public Type
/**
* Returns the Type representing the direct superclass of the entity
* represented by this Class.
*
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* If the superclass is a parameterized type, the Type object returned must
* accurately reflect the actual type parameters used in the source code.
*
getGenericSuperclass();
* ...
*/
public Type
/**
* Returns the Type representing the direct superclass of the entity
* represented by this Class.
*
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* Non-parameterized -> Class
* Parameterized -> ParameterizedType
* If the superclass is a parameterized type, the Type object returned must
* accurately reflect the actual type parameters used in the source code.
*
getGenericSuperclass();
* ...
*/
public Type
/**
* Returns the Type representing the direct superclass of the entity
* represented by this Class.
*
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
getGenericSuperclass();
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
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TypeToken
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return canonicalize(parameterized.getActualTypeArguments()[0]);
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
}
object : TypeToken() {}.type
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TypeToken object : TypeToken() {}.type
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
parameterized.getActualTypeArguments()[0]
canonicalize( );
return
}
}
/**
* Returns a type that is functionally equal but not necessarily equal
* according to Object.equals().
*/
public static Type canonicalize(Type type) { ... }
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parameterized.getActualTypeArguments()[0]
TypeToken object : TypeToken() {}.type
;
public class TypeToken {
final Type type = getSuperclassTypeParameter(getClass());
protected TypeToken() {}
static Type getSuperclassTypeParameter(Class subclass) {
Type superclass = subclass.getGenericSuperclass();
if (superclass instanceof Class) {
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return
}
}
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open constructor
val
fun : * :
val
is <*>
val as
getGenericSuperclass()
getActualTypeArguments()
TypeToken object : TypeToken() {}.type
subclass
getSuperclassTypeParameter Class< >) Type
(
type = getSuperclassTypeParameter( )
class TypeToken
{
{
{
}
}
}
return parameterized.
parameterized =
()
protected
javaClass
if (superclass Class
superclass = subclass.
)
superclass ParameterizedType
RuntimeException("Missing type parameter.")
throw
[0]
actualTypeArguments
genericSuperclass
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: Type requireNotNull token::class.java
if (superclass is Class<*>) {
throw RuntimeException("Missing type parameter.")
}
val parameterized = superclass as ParameterizedType
return parameterized.actualTypeArguments[0]
}
TypeToken object : TypeToken() {}.type
abstract
): Type {
.genericSuperclass
( )
class TypeToken
val token = object : TypeToken() {}
inline makeType
=
val superclass
(
fun
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TypeToken makeType()
: Type requireNotNull token::class.java
if (superclass is Class<*>) {
throw RuntimeException("Missing type parameter.")
}
val parameterized = superclass as ParameterizedType
return parameterized.actualTypeArguments[0]
}
abstract
): Type {
.genericSuperclass
( )
class TypeToken
val token = object : TypeToken() {}
inline makeType
=
val superclass
(
fun
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TypeToken
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, )
}
makeType()
: Type requireNotNull token::class.java
if (superclass is Class<*>) {
throw RuntimeException("Missing type parameter.")
}
val parameterized = superclass as ParameterizedType
return parameterized.actualTypeArguments[0]
}
abstract
): Type {
.genericSuperclass
( )
class TypeToken
val token = object : TypeToken() {}
inline makeType
=
val superclass
(
fun
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TypeToken
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typeOf
inline fun makeType(): Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, makeType())
}
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typeOf
inline fun makeType(): Type
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
inline fun typeOf(): KType
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, makeType())
}
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf())
}
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
inline fun typeOf(): KType
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf())
}
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
inline fun typeOf(): KType
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf())
}
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
inline fun typeOf(): KType
/**
* Returns a Java [Type] instance corresponding
* to the given Kotlin type.
*/
val KType.javaType: Type
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
inline fun typeOf(): KType
/**
* Returns a Java [Type] instance corresponding
* to the given Kotlin type.
*/
val KType.javaType: Type
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
inline fun typeOf(): KType
/**
* Returns a Java [Type] instance corresponding
* to the given Kotlin type.
*/
val KType.javaType: Type
NotImplementedError:
Java type is not yet supported for types
created with createType
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
/**
* Returns a runtime representation of the given
* reified type [T] as an instance of [KType].
*/
/**
* Returns a Java [Type] instance corresponding
* to the given Kotlin type.
*/
val KType.javaType: Type
inline fun typeOf(): KType
NotImplementedError:
Java type is not yet supported for types
created with createType
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makeType
typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
inline fun typeOf(): KType
val KType.javaType: Type
fun KClassifier.createType(...): KType {
...
return KTypeImpl(kotlinType) {
TODO("Java type is not yet supported for types created with createType")
}
}
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typeOf
inline fun typeOf(): KType
val KType.javaType: Type
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, makeType())
}
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typeOf
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
inline fun typeOf(): KType
val KType.javaType: Type
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typeOf
@OptIn(ExperimentalStdlibApi::class)
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
inline fun typeOf(): KType
val KType.javaType: Type
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typeOf
@OptIn(ExperimentalStdlibApi::class)
inline fun Krate.moshiPref(key: String): ReadWriteProperty {
return MoshiDelegate(key, typeOf().javaType)
}
inline fun typeOf(): KType
val KType.javaType: Type
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Resources
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• Krate
https://github.com/AutSoft/Krate
• Moshi
https://github.com/square/moshi
Resources
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• Krate
https://github.com/AutSoft/Krate
• Moshi
https://github.com/square/moshi
• Delightful Delegate Design
https://www.droidcon.com/media-detail?video=481186381
• Say “hi” to Moshi!
https://www.youtube.com/watch?v=qadYVYc-8mc
Resources
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• Krate
https://github.com/AutSoft/Krate
• Moshi
https://github.com/square/moshi
• Delightful Delegate Design
https://www.droidcon.com/media-detail?video=481186381
• Say “hi” to Moshi!
https://www.youtube.com/watch?v=qadYVYc-8mc
• Library design articles
https://zsmb.co/maintaining-compatibility-in-kotlin-libraries/
https://zsmb.co/mastering-api-visibility-in-kotlin/
https://zsmb.co/talks/how-to-build-awesome-android-libraries/
Resources
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zsmb13
zsmb.co/talks
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ft
Krate Moshi
A Kotlin library design case study
zsmb.co/talks
zsmb13
Márton Braun
› Krate is great
› Moshi is awesome
› Type erasure is evil
› Tests are your friend