private static void assertIsMobReference(Cell cell, byte[] row, byte[] family, byte[] value,
    TableName tn) throws IOException {
    Assert.assertArrayEquals(row, CellUtil.cloneRow(cell));
    Assert.assertArrayEquals(family, CellUtil.cloneFamily(cell));
    Assert.assertFalse(Bytes.equals(value, CellUtil.cloneValue(cell)));
    byte[] referenceValue = CellUtil.cloneValue(cell);
    String fileName = MobUtils.getMobFileName(cell);
    int valLen = Bytes.toInt(referenceValue, 0, Bytes.SIZEOF_INT);
    Assert.assertEquals(value.length, valLen);
    Path mobFamilyPath = MobUtils.getMobFamilyPath(TEST_UTIL.getConfiguration(), tn,
      familyDescriptor.getNameAsString());
    Path targetPath = new Path(mobFamilyPath, fileName);
    FileSystem fs = FileSystem.get(TEST_UTIL.getConfiguration());
    Assert.assertTrue(fs.exists(targetPath));
  }
Assert the value is store in mob.
hbase-server/src/test/java/org/apache/hadoop/hbase/mob/TestMobStoreScanner.java