デシリアライズ処理の引数のnullabilityを修正

Author: k163377

src/main/kotlin/com/mapk/deserialization/KColumnDeserialize.kt

@@ -9,5 +9,5 @@ annotation class KColumnDeserializeBy(val deserializer: KClass<out AbstractKColu
 
 abstract class AbstractKColumnDeserializer<A : Annotation, S : Any, D>(protected val annotation: A) {
     abstract val srcClass: Class<S>
-    abstract fun deserialize(source: S?): D?
+    abstract fun deserialize(source: S): D?
 }