Fix clj-kondo warnings in ring-servlet

Author: weavejester

ring-servlet/src/ring/util/servlet.clj

@@ -1,10 +1,8 @@
 (ns ring.util.servlet
   "Compatibility functions for turning a ring handler into a Java servlet."
-  (:require [clojure.java.io :as io]
-            [clojure.string :as string]
+  (:require [clojure.string :as string]
             [ring.core.protocols :as protocols])
-  (:import [java.io File InputStream FileInputStream]
-           [java.util Locale]
+  (:import [java.util Locale]
            [javax.servlet AsyncContext]
            [javax.servlet.http HttpServlet
                                HttpServletRequest
@@ -27,7 +25,7 @@
   "Returns the content length, or nil if there is no content."
   [^HttpServletRequest request]
   (let [length (.getContentLength request)]
-    (if (>= length 0) length)))
+    (when (>= length 0) length)))
 
 (defn- get-client-cert
   "Returns the SSL client certificate of the request, if one exists."