code: static StructTypeInfo getTypeInfo(Configuration conf) {
      StructTypeInfo inputTypeInfo = (StructTypeInfo) TypeInfoUtils.getTypeInfoFromTypeString(conf.get(INPUT_TYPE_INFO));
      LOG.debug("Got input typeInfo from conf: {}", inputTypeInfo);
      return inputTypeInfo;
    }
docs: Gets the StructTypeInfo that declares the columns to be read from the configuration