code: public Date getUTCTime() throws IOException {
          if (tag != tag_UtcTime) {
              throw new IOException("DerValue.getUTCTime, not a UtcTime: " + tag);
          }
          return buffer.getUTCTime(data.available());
      }
docs: Returns a Date if the DerValue is UtcTime.
  
  @return the Date held in this DER value