diff --git a/src/main/java/com/poiji/bind/mapping/SheetNameExtractor.java b/src/main/java/com/poiji/bind/mapping/SheetNameExtractor.java
index b63741c..48d65f6 100644
--- a/src/main/java/com/poiji/bind/mapping/SheetNameExtractor.java
+++ b/src/main/java/com/poiji/bind/mapping/SheetNameExtractor.java
@@ -8,7 +8,12 @@
 /**
  * Utility class to extract the sheet name.
  */
-class SheetNameExtractor {
+final class SheetNameExtractor {
+
+    private SheetNameExtractor() {
+
+    }
+
     /**
      * Extracts the sheet name from either the annotated value {@link ExcelSheet} from the model class or from the sheet name set
      * in the Poiji Options. Poiji first looks at {@link ExcelSheet} then {@link PoijiOptions}.