diff --git a/chatgpt-api/src/main/kotlin/tw/waterballsa/utopia/chatgpt/JTokkit.kt b/chatgpt-api/src/main/kotlin/tw/waterballsa/utopia/chatgpt/JTokkit.kt
index ba901058..e1fb2d1b 100644
--- a/chatgpt-api/src/main/kotlin/tw/waterballsa/utopia/chatgpt/JTokkit.kt
+++ b/chatgpt-api/src/main/kotlin/tw/waterballsa/utopia/chatgpt/JTokkit.kt
@@ -10,14 +10,8 @@ import com.knuddels.jtokkit.api.ModelType
 class JTokkit {
     companion object {
         private val registry = Encodings.newLazyEncodingRegistry()
-        private lateinit var encoding: Encoding
+        private val encoding = registry.getEncodingForModel(ModelType.GPT_3_5_TURBO)
     }
 
-    init {
-        encoding = registry.getEncodingForModel(ModelType.GPT_3_5_TURBO)
-    }
-
-    fun measureNumOfTokens(string: String): Int {
-        return encoding.countTokens(string)
-    }
+    fun measureNumOfTokens(string: String): Int = encoding.countTokens(string)
 }