private boolean addLiteral(List<Object> literals, PredicateLeaf leaf) {
      switch (leaf.getOperator()) {
      case EQUALS:
        return literals.add(
            convertLiteral(leaf.getLiteral()));
      case IN:
        return literals.addAll(
            leaf.getLiteralList().stream().map(l -> convertLiteral(l)).collect(Collectors.toList()));
      default:
        return false;
      }
    }
Fixed bucket pruning optimizer goes through all the table scans and annotates them
with a bucketing inclusion bit-set.
ql/src/java/org/apache/hadoop/hive/ql/optimizer/FixedBucketPruningOptimizer.java