@Test
public void testWhenRowKeyIsNotSet() {

  RowAdapter.RowBuilder<Result> rowBuilder = underTest.createRowBuilder();
  rowBuilder.startCell(COL_FAMILY, QUAL_ONE, 30000L, LABELS, VALUE.size());
  rowBuilder.cellValue(VALUE);
  try {
    rowBuilder.finishCell();
    Assert.fail("should not accept null rowKey");
  } catch (NullPointerException expected) {
    assertEquals("row key cannot be null", expected.getMessage());
  }
}