| /* |
| * 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.java.mapping; |
| |
| import org.apache.wayang.basic.operators.SampleOperator; |
| import org.apache.wayang.core.api.exception.WayangException; |
| import org.apache.wayang.core.mapping.Mapping; |
| import org.apache.wayang.core.mapping.OperatorPattern; |
| import org.apache.wayang.core.mapping.PlanTransformation; |
| import org.apache.wayang.core.mapping.ReplacementSubplanFactory; |
| import org.apache.wayang.core.mapping.SubplanPattern; |
| import org.apache.wayang.core.types.DataSetType; |
| import org.apache.wayang.java.operators.JavaRandomSampleOperator; |
| import org.apache.wayang.java.operators.JavaReservoirSampleOperator; |
| import org.apache.wayang.java.platform.JavaPlatform; |
| |
| import java.util.Collection; |
| import java.util.Collections; |
| |
| /** |
| * Mapping from {@link SampleOperator} to {@link JavaRandomSampleOperator}. |
| */ |
| @SuppressWarnings("unchecked") |
| public class SampleMapping implements Mapping { |
| |
| @Override |
| public Collection<PlanTransformation> getTransformations() { |
| return Collections.singleton(new PlanTransformation( |
| this.createSubplanPattern(), |
| this.createReplacementSubplanFactory(), |
| JavaPlatform.getInstance() |
| )); |
| } |
| |
| private SubplanPattern createSubplanPattern() { |
| final OperatorPattern operatorPattern = new OperatorPattern<>( |
| "sample", new SampleOperator<>(0, DataSetType.none(), null, 0L), false |
| ).withAdditionalTest(op -> |
| op.getSampleMethod() == SampleOperator.Methods.RANDOM |
| || op.getSampleMethod() == SampleOperator.Methods.RESERVOIR |
| || op.getSampleMethod() == SampleOperator.Methods.ANY |
| ); |
| return SubplanPattern.createSingleton(operatorPattern); |
| } |
| |
| private ReplacementSubplanFactory createReplacementSubplanFactory() { |
| return new ReplacementSubplanFactory.OfSingleOperators<SampleOperator>( |
| (matchedOperator, epoch) -> { |
| switch (matchedOperator.getSampleMethod()) { |
| case ANY: |
| case RANDOM: |
| return new JavaRandomSampleOperator<>(matchedOperator).at(epoch); |
| case RESERVOIR: |
| return new JavaReservoirSampleOperator<>(matchedOperator).at(epoch); |
| default: |
| throw new WayangException(String.format( |
| "%s sample method is not yet supported in Java platform.", |
| matchedOperator.getSampleMethod() |
| )); |
| } |
| } |
| ); |
| } |
| } |