diff --git a/lib/http/cookie_jar/abstract_store.rb b/lib/http/cookie_jar/abstract_store.rb
index 0ff2a37..6565ab4 100644
--- a/lib/http/cookie_jar/abstract_store.rb
+++ b/lib/http/cookie_jar/abstract_store.rb
@@ -71,6 +71,10 @@ class HTTP::CookieJar::AbstractStore
   end
   include Enumerable
 
+  def empty?
+    raise
+  end
+
   def clear
     raise
     self