diff --git a/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java b/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java
index cbdc8aa..18e8a94 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java
@@ -153,9 +153,7 @@
 
   @Override
   public void invalidateAll() {
-    for (Path path : listFiles()) {
-      deleteFile(path);
-    }
+    foreachSession(this::deleteFile);
   }
 
   @Override