io.trino.sql.planner.iterative.Plans Maven / Gradle / Ivy
/*
* 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 io.trino.sql.planner.iterative;
import io.trino.sql.planner.plan.PlanNode;
import io.trino.sql.planner.plan.PlanVisitor;
import java.util.List;
import java.util.stream.Collectors;
import static java.util.Objects.requireNonNull;
public final class Plans
{
public static PlanNode resolveGroupReferences(PlanNode node, Lookup lookup)
{
requireNonNull(node, "node is null");
return node.accept(new ResolvingVisitor(lookup), null);
}
private static class ResolvingVisitor
extends PlanVisitor
{
private final Lookup lookup;
public ResolvingVisitor(Lookup lookup)
{
this.lookup = requireNonNull(lookup, "lookup is null");
}
@Override
protected PlanNode visitPlan(PlanNode node, Void context)
{
List children = node.getSources().stream()
.map(child -> child.accept(this, context))
.collect(Collectors.toList());
return node.replaceChildren(children);
}
@Override
public PlanNode visitGroupReference(GroupReference node, Void context)
{
return lookup.resolve(node).accept(this, context);
}
}
private Plans() {}
}