code: public JBBPTextWriter Obj(final int objId, final Object... obj) throws IOException {
      if (this.extras.isEmpty()) {
        throw new IllegalStateException("There is not any registered extras");
      }
  
      for (final Object c : obj) {
        String str = null;
        for (final Extra e : this.extras) {
          str = e.doConvertObjToStr(this, objId, c);
          if (str != null) {
            break;
          }
        }
  
        if (str != null) {
          ensureValueMode();
          printValueString(str);
        }
      }
      return this;
    }
docs: Print objects.
  
  @param objId object id which will be provided to a converter as extra info
  @param obj   objects to be converted and printed, must not be null
  @return the context
  @throws IOException it will be thrown for transport errors