// Hence do not use FirstKeyOnlyFilter if scan has columns, instead use
// FirstKeyValueMatchingQualifiersFilter.
if (qualifiers.size() == 0) {
scan.setFilter(new FirstKeyOnlyFilter());
} else {
scan.setFilter(new FirstKeyValueMatchingQualifiersFilter(qualifiers));
}
scan.setTimeRange(startTime, endTime == 0 ? HConstants.LATEST_TIMESTAMP : endTime);
job.setOutputFormatClass(NullOutputFormat.class);
TableMapReduceUtil.initTableMapperJob(tableName, scan,
RowCounterMapper.class, ImmutableBytesWritable.class, Result.class, job);