code: public String readWhile(String accepted)
  	{
  		int start = cursor;
  		while(cursor < str.length())
  		{
  			if(accepted.indexOf(str.charAt(cursor))>=0)
  				++cursor;
  			else
  				break;
  		}
  		return str.substring(start, cursor);
  	}
docs: Read everything as long as the char occurs in the accepted characters.