| /* |
| * 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.operators; |
| |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.function.Function; |
| import java.util.stream.Stream; |
| import org.apache.wayang.basic.channels.FileChannel; |
| import org.apache.wayang.basic.data.Record; |
| import org.apache.wayang.basic.data.Tuple2; |
| import org.apache.wayang.core.api.exception.WayangException; |
| import org.apache.wayang.core.optimizer.OptimizationContext; |
| import org.apache.wayang.core.plan.wayangplan.ExecutionOperator; |
| import org.apache.wayang.core.plan.wayangplan.Operator; |
| import org.apache.wayang.core.plan.wayangplan.UnarySource; |
| import org.apache.wayang.core.platform.ChannelDescriptor; |
| import org.apache.wayang.core.platform.ChannelInstance; |
| import org.apache.wayang.core.platform.lineage.ExecutionLineageNode; |
| import org.apache.wayang.core.types.DataSetType; |
| import org.apache.wayang.core.util.Tuple; |
| import org.apache.wayang.core.util.fs.FileSystems; |
| import org.apache.wayang.core.util.fs.FileUtils; |
| import org.apache.wayang.java.channels.StreamChannel; |
| import org.apache.wayang.java.execution.JavaExecutor; |
| import org.apache.wayang.java.platform.JavaPlatform; |
| |
| /** |
| * {@link Operator} for the {@link JavaPlatform} that creates a sequence file. Consistent with Spark's object files. |
| * |
| * @see JavaObjectFileSink |
| */ |
| public class JavaTsvFileSource<T> extends UnarySource<T> implements JavaExecutionOperator { |
| |
| private final String sourcePath; |
| |
| public JavaTsvFileSource(String sourcePath, DataSetType type) { |
| super(type); |
| this.sourcePath = sourcePath; |
| } |
| |
| public JavaTsvFileSource(DataSetType<Tuple2> type) { |
| this(null, type); |
| } |
| |
| @Override |
| public Tuple<Collection<ExecutionLineageNode>, Collection<ChannelInstance>> evaluate( |
| ChannelInstance[] inputs, |
| ChannelInstance[] outputs, |
| JavaExecutor javaExecutor, |
| OptimizationContext.OperatorContext operatorContext) { |
| assert outputs.length == this.getNumOutputs(); |
| |
| final String path; |
| if (this.sourcePath == null) { |
| final FileChannel.Instance input = (FileChannel.Instance) inputs[0]; |
| path = input.getSinglePath(); |
| } else { |
| assert inputs.length == 0; |
| path = this.sourcePath; |
| } |
| final String actualInputPath = FileSystems.findActualSingleInputPath(path); |
| Stream<T> stream = this.createStream(actualInputPath); |
| ((StreamChannel.Instance) outputs[0]).accept(stream); |
| |
| return ExecutionOperator.modelLazyExecution(inputs, outputs, operatorContext); |
| } |
| |
| private Stream<T> createStream(String path) { |
| Function<String, T> parser = this::lineParse; |
| |
| return FileUtils.streamLines(path).map(parser); |
| } |
| |
| private T lineParse(String line) { |
| // TODO rewrite in less verbose way. |
| Class typeClass = this.getType().getDataUnitType().getTypeClass(); |
| int tabPos = line.indexOf('\t'); |
| if (tabPos == -1) { |
| if (typeClass == Integer.class) { |
| return (T) Integer.valueOf(line); |
| } else if (typeClass == Float.class) { |
| return (T) Float.valueOf(line); |
| } else if (typeClass == String.class) { |
| return (T) String.valueOf(line); |
| } else throw new WayangException(String.format("Cannot parse TSV file line %s", line)); |
| } else if (typeClass == Record.class) { |
| // TODO: Fix Record parsing. |
| return (T) new Record(); |
| } else if (typeClass == Tuple2.class) { |
| // TODO: Fix Tuple2 parsing |
| return (T) new Tuple2( |
| Integer.valueOf(line.substring(0, tabPos)), |
| Float.valueOf(line.substring(tabPos + 1))); |
| } else |
| throw new WayangException(String.format("Cannot parse TSV file line %s", line)); |
| |
| } |
| |
| @Override |
| public String getLoadProfileEstimatorConfigurationKey() { |
| return "wayang.java.tsvfilesource.load"; |
| } |
| |
| @Override |
| protected ExecutionOperator createCopy() { |
| return new JavaTsvFileSource<>(this.sourcePath, this.getType()); |
| } |
| |
| @Override |
| public List<ChannelDescriptor> getSupportedInputChannels(int index) { |
| return Collections.singletonList(FileChannel.HDFS_TSV_DESCRIPTOR); |
| } |
| |
| @Override |
| public List<ChannelDescriptor> getSupportedOutputChannels(int index) { |
| assert index <= this.getNumOutputs() || (index == 0 && this.getNumOutputs() == 0); |
| return Collections.singletonList(StreamChannel.DESCRIPTOR); |
| } |
| |
| } |