| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.wayang.core.optimizer.cardinality; |
| |
| import org.apache.wayang.core.api.Configuration; |
| import org.apache.wayang.core.optimizer.OptimizationContext; |
| import org.apache.wayang.core.plan.wayangplan.OperatorAlternative; |
| import org.apache.wayang.core.util.Tuple; |
| |
| import java.util.List; |
| import java.util.stream.Collectors; |
| |
| /** |
| * {@link CardinalityPusher} implementation for {@link OperatorAlternative}s. |
| */ |
| public class OperatorAlternativeCardinalityPusher extends AbstractAlternativeCardinalityPusher { |
| |
| /** |
| * Maintains a {@link CardinalityEstimationTraversal} for each {@link OperatorAlternative.Alternative}. |
| */ |
| private final List<Tuple<OperatorAlternative.Alternative, CardinalityEstimationTraversal>> alternativeTraversals; |
| |
| public OperatorAlternativeCardinalityPusher(final OperatorAlternative operatorAlternative, |
| final Configuration configuration |
| ) { |
| super(operatorAlternative); |
| this.alternativeTraversals = operatorAlternative.getAlternatives().stream() |
| .map(alternative -> { |
| final CardinalityEstimationTraversal traversal = |
| CardinalityEstimationTraversal.createPushTraversal(alternative, configuration); |
| return new Tuple<>(alternative, traversal); |
| }) |
| .collect(Collectors.toList()); |
| } |
| |
| @Override |
| public void pushThroughAlternatives(OptimizationContext.OperatorContext opCtx, Configuration configuration) { |
| final OptimizationContext optimizationContext = opCtx.getOptimizationContext(); |
| for (Tuple<OperatorAlternative.Alternative, CardinalityEstimationTraversal> alternativeTraversal : |
| this.alternativeTraversals) { |
| this.pushThroughPath(alternativeTraversal, configuration, optimizationContext); |
| } |
| } |
| |
| /** |
| * Trigger the {@link CardinalityEstimationTraversal} for the given {@code traversal}. |
| */ |
| private void pushThroughPath(Tuple<OperatorAlternative.Alternative, CardinalityEstimationTraversal> traversal, |
| Configuration configuration, |
| OptimizationContext optimizationCtx) { |
| // Perform the push. |
| traversal.field1.traverse(optimizationCtx, configuration); |
| } |
| |
| } |