code: public void setStringContent(String s) throws TLVParserException {
          if (s != null) {
              setContent(Util.toByteArray(s + '\0'));
          } else {
              setContent(new byte[]{'\0'});
          }
      }
docs: Encodes the instance of {@link String}. TLV encoded string is always terminated with a zero octet.
  
  @param s
  string to decode.
  
  @throws TLVParserException