| /** |
| * 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.crunch.io.orc; |
| |
| import java.util.Iterator; |
| |
| import org.apache.crunch.CrunchRuntimeException; |
| import org.apache.crunch.MapFn; |
| import org.apache.crunch.io.FileReaderFactory; |
| import org.apache.crunch.types.PType; |
| import org.apache.hadoop.fs.FileStatus; |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.fs.Path; |
| import org.apache.hadoop.hive.ql.io.orc.OrcInputFormat; |
| import org.apache.hadoop.hive.ql.io.orc.OrcStruct; |
| import org.apache.hadoop.hive.serde2.ColumnProjectionUtils; |
| import org.apache.hadoop.io.NullWritable; |
| import org.apache.hadoop.mapred.FileSplit; |
| import org.apache.hadoop.mapred.JobConf; |
| import org.apache.hadoop.mapred.RecordReader; |
| import org.apache.hadoop.mapred.Reporter; |
| |
| import com.google.common.collect.UnmodifiableIterator; |
| |
| public class OrcFileReaderFactory<T> implements FileReaderFactory<T> { |
| |
| private MapFn<Object, T> inputFn; |
| private OrcInputFormat inputFormat = new OrcInputFormat(); |
| private int[] readColumns; |
| |
| public OrcFileReaderFactory(PType<T> ptype) { |
| this(ptype, null); |
| } |
| |
| public OrcFileReaderFactory(PType<T> ptype, int[] readColumns) { |
| inputFn = ptype.getInputMapFn(); |
| this.readColumns = readColumns; |
| } |
| |
| @Override |
| public Iterator<T> read(FileSystem fs, final Path path) { |
| try { |
| if (!fs.isFile(path)) { |
| throw new CrunchRuntimeException("Not a file: " + path); |
| } |
| |
| inputFn.initialize(); |
| |
| FileStatus status = fs.getFileStatus(path); |
| FileSplit split = new FileSplit(path, 0, status.getLen(), new String[0]); |
| |
| JobConf conf = new JobConf(); |
| if (readColumns != null) { |
| conf.setBoolean(OrcFileSource.HIVE_READ_ALL_COLUMNS, false); |
| conf.set(ColumnProjectionUtils.READ_COLUMN_IDS_CONF_STR, OrcFileSource.getColumnIdsStr(readColumns)); |
| } |
| final RecordReader<NullWritable, OrcStruct> reader = inputFormat.getRecordReader(split, conf, Reporter.NULL); |
| |
| return new UnmodifiableIterator<T>() { |
| |
| private boolean checked = false; |
| private boolean hasNext; |
| private OrcStruct value; |
| private OrcWritable writable = new OrcWritable(); |
| |
| @Override |
| public boolean hasNext() { |
| try { |
| if (value == null) { |
| value = reader.createValue(); |
| } |
| if (!checked) { |
| hasNext = reader.next(NullWritable.get(), value); |
| checked = true; |
| } |
| return hasNext; |
| } catch (Exception e) { |
| throw new CrunchRuntimeException("Error while reading local file: " + path, e); |
| } |
| } |
| |
| @Override |
| public T next() { |
| try { |
| if (value == null) { |
| value = reader.createValue(); |
| } |
| if (!checked) { |
| reader.next(NullWritable.get(), value); |
| } |
| checked = false; |
| writable.set(value); |
| return inputFn.map(writable); |
| } catch (Exception e) { |
| throw new CrunchRuntimeException("Error while reading local file: " + path, e); |
| } |
| } |
| |
| }; |
| } catch (Exception e) { |
| throw new CrunchRuntimeException("Error while reading local file: " + path, e); |
| } |
| } |
| |
| } |