code: private WordMatch checkMatch(String key)
  	{
  		String matchString = key;
  
  		while (matchString.indexOf(' ') > -1)
  		{
  			if (fWords.containsKey(matchString))
  			{
  //				System.out.println("key '"+key+"' not matched: "+(key.length()
  //						- matchString.length()));
  				return new WordMatch((IToken) fWords.get(matchString), key.length()
  						- matchString.length());
  			}
  
  			matchString = matchString.substring(0, matchString.lastIndexOf(' '));
  		}
  
  		return null;
  	}
docs: Checks if the scanned multipart word exists in the {@code fWords} maps keys collection os if the prefix exists.
  
  @param key
  @return