diff --git a/src/main/kotlin/com/mpalourdio/projects/flhacker/FlhackerApplication.kt b/src/main/kotlin/com/mpalourdio/projects/flhacker/FlhackerApplication.kt
index 258acff..8052714 100644
--- a/src/main/kotlin/com/mpalourdio/projects/flhacker/FlhackerApplication.kt
+++ b/src/main/kotlin/com/mpalourdio/projects/flhacker/FlhackerApplication.kt
@@ -23,9 +23,9 @@ class FlhackerApplication {
     fun run(): CommandLineRunner {
         return CommandLineRunner { args ->
             AudiofileHandler.setUp()
-            val cmd: CommandLine? = CliHandler.run(args)
+            val cmd: CommandLine = CliHandler.run(args)
             try {
-                AudiofileHandler.extractResizeSaveArtwork(cmd?.getOptionValue(CliHandler.FILE_CMD_LONG_OPTION))
+                AudiofileHandler.extractResizeSaveArtwork(cmd.getOptionValue(CliHandler.FILE_CMD_LONG_OPTION))
                 AudiofileHandler.generateAsciiArt()
             } finally {
                 AudiofileHandler.tearDown()
diff --git a/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/AudiofileHandler.kt b/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/AudiofileHandler.kt
index d799b5b..a706775 100644
--- a/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/AudiofileHandler.kt
+++ b/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/AudiofileHandler.kt
@@ -48,7 +48,7 @@ object AudiofileHandler {
         ReadOnlyFileException::class,
         IOException::class
     )
-    fun extractResizeSaveArtwork(audioFilePath: String?) {
+    fun extractResizeSaveArtwork(audioFilePath: String) {
         val audioFile = File(audioFilePath)
         val extractedArtwork = AudioFileIO.read(audioFile)
             .tag
diff --git a/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/CliHandler.kt b/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/CliHandler.kt
index b4869d2..4985b11 100644
--- a/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/CliHandler.kt
+++ b/src/main/kotlin/com/mpalourdio/projects/flhacker/utils/CliHandler.kt
@@ -14,7 +14,7 @@ import kotlin.system.exitProcess
 object CliHandler {
     const val FILE_CMD_LONG_OPTION: String = "file"
 
-    fun run(args: Array<String?>?): CommandLine? {
+    fun run(args: Array<String>): CommandLine {
         val options = Options()
         val input =
             Option("f", FILE_CMD_LONG_OPTION, true, "audio file path which contains the artwork to print")