Replace gson with kotlinx-serialization

.gitignore

@@ -67,3 +67,6 @@ fastlane/Preview.html
 fastlane/screenshots
 fastlane/test_output
 fastlane/readme.md
+
+# kotlin
+.kotlin/

.idea/kotlinc.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="1.9.10" />
+    <option name="version" value="2.0.20" />
   </component>
 </project>

app/build.gradle

@@ -2,6 +2,7 @@ plugins {
     id 'com.android.application'
     id 'kotlin-android'
     id 'com.google.devtools.ksp'
+    id 'org.jetbrains.kotlin.plugin.serialization'
 }
 
 android {
@@ -51,11 +52,12 @@ dependencies {
     implementation 'androidx.appcompat:appcompat:1.7.0'
     implementation 'androidx.recyclerview:recyclerview:1.3.2'
     implementation 'androidx.activity:activity-ktx:1.9.2'
-    implementation 'androidx.fragment:fragment-ktx:1.8.3'
+    implementation 'androidx.fragment:fragment-ktx:1.8.4'
     implementation 'com.google.android.material:material:1.12.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
     implementation 'com.google.guava:guava:33.1.0-android'
-    implementation 'com.google.code.gson:gson:2.11.0'
+    implementation 'org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.3'
+
 
     def shizuku_version = '13.1.5'
     implementation "dev.rikka.shizuku:api:$shizuku_version"
@@ -71,7 +73,7 @@ dependencies {
     androidTestImplementation "androidx.room:room-testing:$roomVersion"
 
     // Lifecycle components
-    def lifecycleVersion = '2.8.5'
+    def lifecycleVersion = '2.8.6'
     implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycleVersion"
     implementation "androidx.lifecycle:lifecycle-livedata-ktx:$lifecycleVersion"
     implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycleVersion"

app/src/main/java/ru/karasevm/privatednstoggle/model/DnsServer.kt

@@ -3,19 +3,21 @@ package ru.karasevm.privatednstoggle.model
 import androidx.room.ColumnInfo
 import androidx.room.Entity
 import androidx.room.PrimaryKey
-import com.google.gson.annotations.SerializedName
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
 
 // All fields must have default values for proper deserialization
+@Serializable
 @Entity(tableName = "dns_servers")
 data class DnsServer(
-    @SerializedName("id")
+    @SerialName("id")
     @PrimaryKey(autoGenerate = true)
     val id: Int = 0,
-    @SerializedName("server")
+    @SerialName("server")
     val server: String = "",
-    @SerializedName("label")
+    @SerialName("label")
     val label: String = "",
-    @SerializedName("enabled")
+    @SerialName("enabled")
     @ColumnInfo(defaultValue = "1")
     val enabled: Boolean = true,
     val sortOrder: Int? = null

app/src/main/java/ru/karasevm/privatednstoggle/ui/MainActivity.kt

@@ -27,12 +27,9 @@ import androidx.recyclerview.widget.ItemTouchHelper.DOWN
 import androidx.recyclerview.widget.ItemTouchHelper.UP
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
-import com.google.gson.Gson
-import com.google.gson.GsonBuilder
-import com.google.gson.JsonSyntaxException
-import com.google.gson.ToNumberPolicy
-import com.google.gson.reflect.TypeToken
 import kotlinx.coroutines.launch
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.Json
 import org.lsposed.hiddenapibypass.HiddenApiBypass
 import rikka.shizuku.Shizuku
 import rikka.shizuku.ShizukuBinderWrapper
@@ -58,7 +55,6 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
     private lateinit var sharedPrefs: SharedPreferences
     private lateinit var adapter: ServerListRecyclerAdapter
     private lateinit var clipboard: ClipboardManager
-    private lateinit var gson: Gson
     private val dnsServerViewModel: DnsServerViewModel by viewModels { DnsServerViewModelFactory((application as PrivateDNSApp).repository) }
 
     private val itemTouchHelper by lazy {
@@ -126,7 +122,7 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
 
     private fun importSettings(json: String) {
         runCatching {
-            val data: BackupUtils.Backup = gson.fromJson(json, BackupUtils.Backup::class.java)
+            val data: BackupUtils.Backup = Json.decodeFromString<BackupUtils.Backup>(json)
             BackupUtils.import(data, dnsServerViewModel, sharedPrefs)
         }.onSuccess {
             Toast.makeText(
@@ -134,28 +130,18 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
             ).show()
         }.onFailure { exception ->
             runCatching {
-                val objectType = object : TypeToken<Map<String, Any>>() {}.type
+                Log.e("IMPORT", "Malformed json, falling back to legacy", exception)
-                val data: Map<String, Any> = gson.fromJson(json, objectType)
+                val data = Json.decodeFromString<BackupUtils.LegacyBackup>(json)
                 BackupUtils.importLegacy(data, dnsServerViewModel, sharedPrefs)
             }.onSuccess {
                 Toast.makeText(
                     this, getString(R.string.import_success), Toast.LENGTH_SHORT
                 ).show()
-            }.onFailure {
+            }.onFailure { exception ->
                 Log.e("IMPORT", "Import failed", exception)
-                when (exception) {
+                Toast.makeText(
-                    is JsonSyntaxException -> {
+                    this, getString(R.string.import_failure), Toast.LENGTH_SHORT
-                        Toast.makeText(
+                ).show()
-                            this, getString(R.string.import_failure_json), Toast.LENGTH_SHORT
-                        ).show()
-                    }
-
-                    else -> {
-                        Toast.makeText(
-                            this, getString(R.string.import_failure), Toast.LENGTH_SHORT
-                        ).show()
-                    }
-                }
             }
         }
     }
@@ -193,7 +179,6 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
 
         sharedPrefs = PreferenceHelper.defaultPreference(this)
         clipboard = getSystemService(CLIPBOARD_SERVICE) as ClipboardManager
-        gson = GsonBuilder().setObjectToNumberStrategy(ToNumberPolicy.LONG_OR_DOUBLE).create()
 
         migrateServerList()
 
@@ -249,7 +234,7 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
                 R.id.export_settings_clipboard -> {
                     dnsServerViewModel.viewModelScope.launch {
                         val data = BackupUtils.export(dnsServerViewModel, sharedPrefs)
-                        val jsonData = gson.toJson(data)
+                        val jsonData = Json.encodeToString(data)
                         clipboard.setPrimaryClip(ClipData.newPlainText("", jsonData))
                         // Only show a toast for Android 12 and lower.
                         if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.S_V2) Toast.makeText(
@@ -263,7 +248,7 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
                     val activityContext = this
                     dnsServerViewModel.viewModelScope.launch {
                         val data = BackupUtils.export(dnsServerViewModel, sharedPrefs)
-                        val jsonData = gson.toJson(data)
+                        val jsonData = Json.encodeToString(data)
                         ShareCompat.IntentBuilder(activityContext).setText(jsonData)
                             .setType("text/plain")
                             .startChooser()
@@ -319,7 +304,7 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
             if (result.resultCode == RESULT_OK) {
                 val data: Intent? = result.data
                 data?.data?.also { uri ->
-                    val jsonData = gson.toJson(BackupUtils.export(dnsServerViewModel, sharedPrefs))
+                    val jsonData = Json.encodeToString(BackupUtils.export(dnsServerViewModel, sharedPrefs))
                     val contentResolver = applicationContext.contentResolver
                     runCatching {
                         contentResolver.openOutputStream(uri)?.use { outputStream ->

app/src/main/java/ru/karasevm/privatednstoggle/util/BackupUtils.kt

@@ -1,20 +1,26 @@
 package ru.karasevm.privatednstoggle.util
 
 import android.content.SharedPreferences
-import com.google.gson.annotations.SerializedName
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
 import ru.karasevm.privatednstoggle.data.DnsServerViewModel
 import ru.karasevm.privatednstoggle.model.DnsServer
-import ru.karasevm.privatednstoggle.util.PreferenceHelper.AUTO_MODE
-import ru.karasevm.privatednstoggle.util.PreferenceHelper.DNS_SERVERS
-import ru.karasevm.privatednstoggle.util.PreferenceHelper.REQUIRE_UNLOCK
 import ru.karasevm.privatednstoggle.util.PreferenceHelper.autoMode
 import ru.karasevm.privatednstoggle.util.PreferenceHelper.requireUnlock
 
 object BackupUtils {
+    @Serializable
     data class Backup(
-        @SerializedName("dns_servers") val dnsServers: List<DnsServer>,
+        @SerialName("dns_servers") val dnsServers: List<DnsServer>,
-        @SerializedName("auto_mode") val autoMode: Int?,
+        @SerialName("auto_mode") val autoMode: Int?,
-        @SerializedName("require_unlock") val requireUnlock: Boolean?,
+        @SerialName("require_unlock") val requireUnlock: Boolean?,
+    )
+
+    @Serializable
+    data class LegacyBackup(
+        @SerialName("dns_servers") val dnsServers: String,
+        @SerialName("auto_mode") val autoMode: Int?,
+        @SerialName("require_unlock") val requireUnlock: Boolean?,
     )
 
     /**
@@ -47,17 +53,16 @@ object BackupUtils {
 
     /**
      *  Imports old server list
-     *  @param map Deserialized backup
+     *  @param legacyBackup Deserialized backup
      *  @param viewModel View model
      *  @param sharedPreferences Shared preferences
      */
     fun importLegacy(
-        map: Map<String, Any>,
+        legacyBackup: LegacyBackup,
         viewModel: DnsServerViewModel,
         sharedPreferences: SharedPreferences
     ) {
-        map[DNS_SERVERS]?.let { servers ->
+        legacyBackup.dnsServers.let { servers ->
-            if (servers is String) {
                 val serverList = servers.split(",")
                 serverList.forEach { server ->
                     val parts = server.split(" : ")
@@ -67,9 +72,8 @@ object BackupUtils {
                         viewModel.insert(DnsServer(0, server, ""))
                     }
                 }
-            }
         }
-        sharedPreferences.autoMode = map[AUTO_MODE] as? Int ?: 0
+        sharedPreferences.autoMode = legacyBackup.autoMode?: 0
-        sharedPreferences.requireUnlock = map[REQUIRE_UNLOCK] as? Boolean ?: false
+        sharedPreferences.requireUnlock = legacyBackup.requireUnlock?: false
     }
 }

build.gradle

@@ -6,15 +6,16 @@ buildscript {
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:8.5.2'
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.9.10"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:2.0.20"
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
     }
 }
 plugins {
-    id 'org.jetbrains.kotlin.android' version '1.9.10' apply false
+    id 'org.jetbrains.kotlin.android' version '2.0.20' apply false
-    id "com.google.devtools.ksp" version "1.9.10-1.0.13" apply false
+    id 'org.jetbrains.kotlin.plugin.serialization' version '2.0.20'
+    id "com.google.devtools.ksp" version "2.0.20-1.0.25" apply false
 }
 
 tasks.register('clean', Delete) {