code: public static Sample ofTimeText(long time, String textValue) {
          return new Sample(time, null, null, textValue);
      }
docs: Creates a new {@link Sample} with time and text value specified
  
  @param  time         time in milliseconds from 1970-01-01 00:00:00
  @param  textValue    the text value of the sample
  @return the Sample with specified fields