@Override public String toString(){
  int len=_value.length();
  len=len + 2 + (len >> 4);
  StringBuilder sb=new StringBuilder(len);
  appendQuoted(sb,_value);
  return sb.toString();
}

@ Override public String toString ( ) { int len = _value . length ( ) ; len = len + 2 + ( len > > 4 ) ; StringBuilder sb = new StringBuilder ( len ) ; appendQuoted ( sb , _value ) ; return sb . toString ( ) ; }
different from other values , strings need quoting
