@BeforeClass
  public static void beforeClass() throws Exception {
    // Up the handlers; this test needs more than usual.
    UTIL.getConfiguration().setInt(HConstants.REGION_SERVER_HIGH_PRIORITY_HANDLER_COUNT, 10);
    UTIL.startMiniCluster();
    Table table = UTIL.createMultiRegionTable(MULTI_REGION_TABLE_NAME,
      new byte[][] { INPUT_FAMILY, OUTPUT_FAMILY });
    UTIL.loadTable(table, INPUT_FAMILY, false);
    UTIL.waitUntilAllRegionsAssigned(MULTI_REGION_TABLE_NAME);
  }
Test Map/Reduce job over HBase tables. The map/reduce process we're testing on our tables is
simple - take every row in the table, reverse the value of a particular cell, and write it back
to the table.
hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestMultithreadedTableMapper.java