| /* |
| * 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.plan.wayangplan; |
| |
| import org.apache.wayang.core.api.Configuration; |
| import org.apache.wayang.core.optimizer.cardinality.CardinalityPusher; |
| import org.apache.wayang.core.optimizer.cardinality.LoopHeadAlternativeCardinalityPusher; |
| import org.apache.wayang.core.util.WayangCollections; |
| |
| import java.util.Collection; |
| import java.util.Objects; |
| import java.util.stream.Collectors; |
| |
| /** |
| * Special {@link OperatorAlternative} for {@link LoopHeadOperator}s. |
| */ |
| public class LoopHeadAlternative extends OperatorAlternative implements LoopHeadOperator { |
| |
| private final LoopHeadOperator originalLoopHead; |
| |
| private Collection<OutputSlot<?>> loopBodyOutputs, finalLoopOutputs; |
| |
| private Collection<InputSlot<?>> loopBodyInputs, initializationInputs; |
| |
| /** |
| * Creates a new instance. |
| * |
| * @param loopHead original {@link LoopHeadOperator} to be wrapped |
| */ |
| LoopHeadAlternative(LoopHeadOperator loopHead) { |
| super(loopHead); |
| this.originalLoopHead = loopHead; |
| } |
| |
| @Override |
| public Alternative addAlternative(Operator alternativeOperator) { |
| assert alternativeOperator.isLoopHead(); |
| assert !this.getAlternatives().isEmpty() || alternativeOperator == this.originalLoopHead; |
| Alternative alternative = super.addAlternative(alternativeOperator); |
| if (this.getAlternatives().size() == 1) { |
| final Alternative originalAlternative = this.getAlternatives().get(0); |
| this.loopBodyInputs = this.originalLoopHead.getLoopBodyInputs().stream() |
| .map(originalAlternative.getSlotMapping()::resolveUpstream).filter(Objects::nonNull) |
| .collect(Collectors.toList()); |
| this.initializationInputs = this.originalLoopHead.getLoopInitializationInputs().stream() |
| .map(originalAlternative.getSlotMapping()::resolveUpstream).filter(Objects::nonNull) |
| .collect(Collectors.toList()); |
| this.loopBodyOutputs = this.originalLoopHead.getLoopBodyOutputs().stream() |
| .map(originalAlternative.getSlotMapping()::resolveDownstream) |
| .map(WayangCollections::getSingleOrNull) |
| .filter(Objects::nonNull) |
| .collect(Collectors.toList()); |
| this.finalLoopOutputs = this.originalLoopHead.getFinalLoopOutputs().stream() |
| .map(originalAlternative.getSlotMapping()::resolveDownstream) |
| .map(WayangCollections::getSingleOrNull) |
| .filter(Objects::nonNull) |
| .collect(Collectors.toList()); |
| } |
| return alternative; |
| } |
| |
| @Override |
| public Collection<OutputSlot<?>> getLoopBodyOutputs() { |
| return this.loopBodyOutputs; |
| } |
| |
| @Override |
| public Collection<OutputSlot<?>> getFinalLoopOutputs() { |
| return this.finalLoopOutputs; |
| } |
| |
| @Override |
| public Collection<InputSlot<?>> getLoopBodyInputs() { |
| return this.loopBodyInputs; |
| } |
| |
| @Override |
| public Collection<InputSlot<?>> getLoopInitializationInputs() { |
| return this.initializationInputs; |
| } |
| |
| @Override |
| public Collection<InputSlot<?>> getConditionInputSlots() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public Collection<OutputSlot<?>> getConditionOutputSlots() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public int getNumExpectedIterations() { |
| return this.originalLoopHead.getNumExpectedIterations(); |
| } |
| |
| @Override |
| public CardinalityPusher getCardinalityPusher(Configuration configuration) { |
| return new LoopHeadAlternativeCardinalityPusher( |
| this, |
| this.getLoopBodyInputs(), |
| this.getLoopBodyOutputs(), |
| (alternative, conf) -> alternative.getContainedOperator().getCardinalityPusher(conf), |
| configuration |
| ); |
| } |
| |
| @Override |
| public CardinalityPusher getInitializationPusher(Configuration configuration) { |
| return new LoopHeadAlternativeCardinalityPusher( |
| this, |
| this.getLoopInitializationInputs(), |
| this.getLoopBodyOutputs(), |
| (alternative, conf) -> ((LoopHeadOperator) alternative.getContainedOperator()).getInitializationPusher(conf), |
| configuration |
| ); |
| } |
| |
| @Override |
| public CardinalityPusher getFinalizationPusher(Configuration configuration) { |
| return new LoopHeadAlternativeCardinalityPusher( |
| this, |
| this.getLoopBodyInputs(), |
| this.getFinalLoopOutputs(), |
| (alternative, conf) -> ((LoopHeadOperator) alternative.getContainedOperator()).getFinalizationPusher(conf), |
| configuration |
| ); |
| } |
| } |