code: public URL registerInMemoryResource(final InMemoryMappingFile file) {
          URL url = DoPrivHelper.newInMemoryMappingFileURL(file);
          _resourceMap.put(file.getName(), url);
  
          return url;
      }
docs: Registers the provided InMemoryMappingFile with our ClassLoader. This allows this resource
  to be looked up via ClassLoader.getResource(fileName).