code: public void addBlackListedHost(final String spec) throws ConfigurationException, FileNotFoundException 	{
  		if (spec.length() == 0) return; // Skip empty specs
  		if (spec.startsWith("file:")) {
  			final LineIterator lineIterator = new LineIterator(new FastBufferedReader(new InputStreamReader(new FileInputStream(spec.substring(5)), Charsets.ISO_8859_1)));
  			while (lineIterator.hasNext()) {
  				final MutableString line = lineIterator.next();
  				blackListedHostHashes.add(line.toString().trim().hashCode());
  			}
  		}
  		else blackListedHostHashes.add(spec.trim().hashCode());
  	}
docs: Adds a (or a set of) new host to the black list; the host can be specified directly or it can be a file (prefixed by
  <code>file:</code>).
  
  @param spec the specification (a host, or a file prefixed by <code>file</code>).
  @throws ConfigurationException
  @throws FileNotFoundException