@Deprecated // to be removed before 2.0
  public void getChildFactors(HiveLoptJoinTree joinTree,
                              ImmutableBitSet.Builder childFactors) {
    for (int child : joinTree.getTreeOrder()) {
      childFactors.set(child);
    }
  }
Sets a bitmap indicating all child RelNodes in a join tree.

@param joinTree join tree to be examined
@param childFactors bitmap to be set
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveLoptMultiJoin.java