code: public void reload() {
          providers = new HashSet<Metadata<S>>();
  
          for (URL serviceFile : loadServiceFiles()) {
              loadServiceFile(serviceFile);
          }
      }
docs: Clear this loader's provider cache so that all providers will be reloaded.
  <p/>
  After invoking this method, subsequent invocations of the iterator method
  will lazily look up and instantiate providers from scratch, just as is
  done by a newly-created loader.
  <p/>
  This method is intended for use in situations in which new providers can
  be installed into a running Java virtual machine.