code: @NonNull
      public Calendar getTimestamp(@NonNull String reportFileName) {
          final String timestamp = reportFileName.replace(ACRAConstants.REPORTFILE_EXTENSION, "").replace(ACRAConstants.SILENT_SUFFIX, "");
          final Calendar calendar = Calendar.getInstance();
          try {
              calendar.setTime(new SimpleDateFormat(ACRAConstants.DATE_TIME_FORMAT_STRING, Locale.ENGLISH).parse(timestamp));
          } catch (ParseException ignored) {
          }
          return calendar;
      }
docs: Gets the timestamp of a report from its name
  
  @param reportFileName Name of the report to get the timestamp from.
  @return timestamp of the report