code: private String checkAndTrimPathArg(String path) {
  		// disallow construction of a Path from an empty string
  		if (path == null) {
  			throw new IllegalArgumentException("Can not create a Path from a null string");
  		}
  		path = path.trim();
  		if (path.length() == 0) {
  			throw new IllegalArgumentException("Can not create a Path from an empty string");
  		}
  		return path;
  	}
docs: Checks if the provided path string is either null or has zero length and throws
  a {@link IllegalArgumentException} if any of the two conditions apply.
  In addition, leading and tailing whitespaces are removed.
  
  @param path
  the path string to be checked
  @return The checked and trimmed path.