@Override
  protected void initJob(List<Scan> scans, Job job) throws IOException {
    TableMapReduceUtil.initTableMapperJob(scans, ScanMapper.class, ImmutableBytesWritable.class,
      ImmutableBytesWritable.class, job);
  }
Tests various scan start and stop row scenarios. This is set in a scan and tested in a MapReduce
job to see if that is handed over and done properly too.
hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestMultiTableInputFormat.java