code: public String read(final String filename) {
          if (isFresh(filename)) {
              String cachedValue = getFileFromCache(filename);
              if (cachedValue != null) {
                  return cachedValue;
              }
          }
          // either fresh is false or cachedValue is null
          loadToCache(filename);
          return getFileFromCache(filename);
      }
docs: Loads a resource from the filesystem into a string.
  
  Verifies if the file last modified date is newer than on the cache
  if it is loads into a string
  returns the string or the cached value