src/java.desktop/share/classes/sun/awt/SunToolkit.java

*** 841,856 ****
--- 841,862 ----
      protected static boolean imageCached(Object key) {
          return imgCache.containsKey(key);
      }
  
      protected static boolean imageExists(String filename) {
+         if (filename == null) {
+             return false;
+         }
          checkPermissions(filename);
          return filename != null && new File(filename).exists();
      }
  
      @SuppressWarnings("try")
      protected static boolean imageExists(URL url) {
+         if (url == null) {
+             return false;
+         }
          checkPermissions(url);
          if (url != null) {
              try (InputStream is = url.openStream()) {
                  return true;
              }catch(IOException e){