/* * Copyright (C) 2017-2019 Dremio Corporation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.dremio.exec.planner.physical; import org.apache.calcite.plan.ConventionTraitDef; import org.apache.calcite.plan.RelOptRule; import org.apache.calcite.plan.RelOptRuleCall; import org.apache.calcite.plan.RelTrait; import org.apache.calcite.plan.RelTraitSet; import org.apache.calcite.plan.volcano.RelSubset; import org.apache.calcite.rel.RelNode; public abstract class SubsetTransformer<T extends RelNode, E extends Exception> { static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(SubsetTransformer.class); public abstract RelNode convertChild(T current, RelNode child) throws E; private final RelOptRuleCall call; public SubsetTransformer(RelOptRuleCall call) { this.call = call; } public RelTraitSet newTraitSet(RelTrait... traits) { RelTraitSet set = call.getPlanner().emptyTraitSet(); for (RelTrait t : traits) { set = set.plus(t); } return set; } boolean go(T n, RelNode candidateSet) throws E { if ( !(candidateSet instanceof RelSubset) ) { return false; } boolean transform = false; for (RelNode rel : ((RelSubset)candidateSet).getRelList()) { if (isPhysical(rel)) { RelNode newRel = RelOptRule.convert(candidateSet, rel.getTraitSet().plus(Prel.PHYSICAL).simplify()); RelNode out = convertChild(n, newRel); if (out != null) { call.transformTo(out); transform = true; } } } return transform; } private boolean isPhysical(RelNode n){ return n.getTraitSet().getTrait(ConventionTraitDef.INSTANCE).equals(Prel.PHYSICAL); } }