return sb.toString();
return sb.toString().trim();
    public static String joinStrings(String[] strings, String joinStr)    {        if ( strings == null )            return null;        else if ( strings.length < 1 || joinStr == null )            return "";                StringBuffer sb = new StringBuffer();        for(int i = 0; i < strings.length; i++) {            sb.append(strings[i]);            if ( i+1 < strings.length )                sb.append(joinStr);        }                return sb.toString();    }