code: public static String ensureAbsolutePath(String path) {
  		if (path == null || path.isEmpty()) {
  			return String.valueOf(PATH_SEPARATOR);
  		}
  
  		return path.charAt(0) == PATH_SEPARATOR ? path : PATH_SEPARATOR + path;
  	}
docs: Ensure that given path is an absolute path (i.e starts with {@code '/'}.
  
  @param path The path.
  @return Absolute path.