@Test(dependsOnMethods = {"testCorrectInitialization"})
 public void testExomeSize() {
   int size = 0;
   for (final SimpleInterval loc : nonOverlappingExomeIntervals) {
     size += loc.size();
   }
   Assert.assertEquals(exonDB.exomeSize(), size);
 }
  /**
   * Writes the row in the main matrix output file for a target and, if requested, the corresponding
   * row in the row summary output file.
   *
   * @param countBuffer the counts for the target.
   * @param index the index of target within the target collection.
   */
  private void writeOutputRows(
      final int[] countBuffer, final long[] columnTotals, final int index) {
    final String countString =
        IntStream.range(0, countBuffer.length)
            .mapToObj(i -> transform.apply(countBuffer[i], columnTotals[i]))
            .collect(Collectors.joining(COLUMN_SEPARATOR));
    final String targetInfoString =
        targetOutInfo.composeTargetOutInfoString(index, targetCollection);

    outputWriter.println(String.join(COLUMN_SEPARATOR, targetInfoString, countString));

    if (rowSummaryOutputWriter != null) {
      final long sum = MathUtils.sum(countBuffer);
      final SimpleInterval location = targetCollection.location(index);
      final int targetSize = location.size();
      rowSummaryOutputWriter.println(
          String.join(
              COLUMN_SEPARATOR,
              targetInfoString,
              Long.toString(sum),
              String.format(
                  AVERAGE_DOUBLE_FORMAT, sum / ((float) countColumns.columnCount() * targetSize))));
    }
  }