code: public JsonWriter name(String name) throws IOException {
      if (name == null) {
        throw new NullPointerException("name == null");
      }
      if (deferredName != null) {
        throw new IllegalStateException();
      }
      deferredName = name;
      return this;
    }
docs: Encodes the property name.
  
  @param name the name of the forthcoming value. May not be null.
  @return this writer.