@Override
  public void setConf(Configuration configuration) {
    // TODO MS-SPLIT for now, keep a copy of HiveConf around as we need to call other methods with
    // it. This should be changed to Configuration once everything that this calls that requires
    // HiveConf is moved to the standalone metastore.
    //clone the conf - compactor needs to set properties in it which we don't
    // want to bleed into the caller
    conf = new HiveConf(configuration, HiveConf.class);
  }
Superclass for all threads in the compactor.
ql/src/java/org/apache/hadoop/hive/ql/txn/compactor/CompactorThread.java