diff --git a/src/Condition/In.php b/src/Condition/In.php
index <HASH>..<HASH> 100644
--- a/src/Condition/In.php
+++ b/src/Condition/In.php
@@ -43,7 +43,7 @@ class In extends AbstractSpecification
      *
      * @return string
      */
-    protected function generateParameterName(QueryBuilder $queryBuilder)
+    private function generateParameterName(QueryBuilder $queryBuilder)
     {
         return sprintf('in_%d', count($queryBuilder->getParameters()));
     }
method should be private because it is overriden