@Test
  public void testScan_NullQualifier() throws IOException {
    try (Table table = TEST_UTIL.createTable(name.getTableName(), FAMILY)) {
      Put put = new Put(ROW);
      put.addColumn(FAMILY, QUALIFIER, VALUE);
      table.put(put);

      put = new Put(ROW);
      put.addColumn(FAMILY, null, VALUE);
      table.put(put);
      LOG.info("Row put");

      Scan scan = new Scan();
      scan.addColumn(FAMILY, null);

      ResultScanner scanner = table.getScanner(scan);
      Result[] bar = scanner.next(100);
      assertEquals(1, bar.length);
      assertEquals(1, bar[0].size());

      scan = new Scan();
      scan.addFamily(FAMILY);

      scanner = table.getScanner(scan);
      bar = scanner.next(100);
      assertEquals(1, bar.length);
      assertEquals(2, bar[0].size());
    }
  }
Tests getRegionsInRange by creating some regions over which a range of keys spans; then
changing the key range.
hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide5.java