code: public ResourceList nonClassFilesOnly() {
          return filter(new ResourceFilter() {
              @Override
              public boolean accept(final Resource resource) {
                  return !CLASSFILE_FILTER.accept(resource);
              }
          });
      }
docs: Return a new {@link ResourceList} consisting of non-classfile resources only.
  
  @return A new {@link ResourceList} consisting of only the resources that do not have the filename extension
  ".class".