@Override
    public void onMatch(RelOptRuleCall call) {
      LOG.debug("JDBCExpandExpressionsRule.FilterCondition has been called");

      final JdbcFilter filter = call.rel(0);
      final RexNode condition = filter.getCondition();

      RexNode newCondition = analyzeRexNode(
          filter.getCluster().getRexBuilder(), condition);

      // If we could not transform anything, we bail out
      if (newCondition.toString().equals(condition.toString())) {
        return;
      }

      RelNode newNode = filter.copy(filter.getTraitSet(), filter.getInput(), newCondition);
      call.transformTo(newNode);
    }
Rule adapter to apply the transformation to Filter conditions.
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/jdbc/JDBCExpandExpressionsRule.java