@Test
  public void testBulkOutputWithoutAnExistingTable() throws Exception {
    // Prepare the arguments required for the test.
    Path hfiles = new Path(util.getDataTestDirOnTestFS(tn.getNameAsString()), "hfiles");
    args.put(ImportTsv.BULK_OUTPUT_CONF_KEY, hfiles.toString());

    doMROnTableTest(null, 3);
    util.deleteTable(tn);
  }
Force use of combiner in doMROnTableTest. Boolean. Default is true.
hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportTsv.java