code: public static final FileAttribute<?>[] getFileAttributes(Map<String, ?> env)
      {
          FileAttribute<?>[] attrs = (FileAttribute<?>[]) env.get(FILE_ATTRIBUTES);
          if (attrs == null)
          {
              attrs = new FileAttribute<?>[0];
          }
          return attrs;
      }
docs: Return file attributes from env or empty array. These attributes are used
  in creating archive file. Because of zip-file-system crashes if trying to
  open file system for not existing file.
  @param env
  @return