private static function unicodeEscape($ch, $charVector)
 {
     $charVector .= self::JS_ESCAPE_CHAR;
     $ich = Charactor::ord($ch);
     if ($ich < self::NUMBER_OF_JS_ESCAPED_CHARS && isset(self::$JS_CHARS_ESCAPED[$ch])) {
         $charVector .= self::$JS_CHARS_ESCAPED[$ch];
     } else {
         if ($ich < 256) {
             $charVector .= 'x' . self::$NIBBLE_TO_HEX_CHAR[$ich >> 4 & 0xf] . self::$NIBBLE_TO_HEX_CHAR[$ich & 0xf];
         } else {
             $charVector .= 'u' . self::$NIBBLE_TO_HEX_CHAR[$ich >> 12 & 0xf] . self::$NIBBLE_TO_HEX_CHAR[$ich >> 8 & 0xf] . self::$NIBBLE_TO_HEX_CHAR[$ich >> 4 & 0xf] . self::$NIBBLE_TO_HEX_CHAR[$ich & 0xf];
         }
     }
 }