Add error catch on FXMLLoader

src/main/java/app/Main.java

@@ -24,7 +24,15 @@ public class Main extends Application {
   public void start(Stage window) throws IOException {
     window.setTitle("Hello world");
 
-    Parent document = FXMLLoader.load(getClass().getResource("/fxml/Main.fxml"));
+    FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/fxml/Main.fxml"));
+    Parent document;
+
+    try {
+      document = fxmlLoader.load();
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+
     Scene scene = new Scene(document);
     window.setScene(scene);
     window.show();