| /** |
| * 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.distributedlog.mapreduce; |
| |
| import org.apache.distributedlog.*; |
| import org.apache.bookkeeper.client.BKException; |
| import org.apache.bookkeeper.client.BookKeeper; |
| import org.apache.bookkeeper.client.LedgerEntry; |
| import org.apache.bookkeeper.client.LedgerHandle; |
| import org.apache.hadoop.mapreduce.InputSplit; |
| import org.apache.hadoop.mapreduce.RecordReader; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| |
| import java.io.IOException; |
| import java.util.Enumeration; |
| |
| import static com.google.common.base.Charsets.UTF_8; |
| |
| /** |
| * Record Reader to read from a log segment split |
| */ |
| class LogSegmentReader extends RecordReader<DLSN, LogRecordWithDLSN> { |
| |
| final String streamName; |
| final BookKeeper bk; |
| final LedgerHandle lh; |
| final LogSegmentMetadata metadata; |
| |
| long entryId = -1L; |
| Entry.Reader reader = null; |
| LogRecordWithDLSN currentRecord = null; |
| int readPos = 0; |
| |
| LogSegmentReader(String streamName, |
| DistributedLogConfiguration conf, |
| BookKeeper bk, |
| LogSegmentSplit split) |
| throws IOException { |
| this.streamName = streamName; |
| this.bk = bk; |
| this.metadata = split.getMetadata(); |
| try { |
| this.lh = bk.openLedgerNoRecovery( |
| split.getLogSegmentId(), |
| BookKeeper.DigestType.CRC32, |
| conf.getBKDigestPW().getBytes(UTF_8)); |
| } catch (BKException e) { |
| throw new IOException(e); |
| } catch (InterruptedException e) { |
| Thread.currentThread().interrupt(); |
| throw new IOException(e); |
| } |
| } |
| |
| @Override |
| public void initialize(InputSplit split, TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| // do nothing |
| } |
| |
| @Override |
| public boolean nextKeyValue() |
| throws IOException, InterruptedException { |
| LogRecordWithDLSN record; |
| currentRecord = null; |
| if (null != reader) { |
| record = reader.nextRecord(); |
| if (null != record) { |
| currentRecord = record; |
| readPos = record.getPositionWithinLogSegment(); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| ++entryId; |
| if (entryId > lh.getLastAddConfirmed()) { |
| return false; |
| } |
| try { |
| Enumeration<LedgerEntry> entries = |
| lh.readEntries(entryId, entryId); |
| if (entries.hasMoreElements()) { |
| LedgerEntry entry = entries.nextElement(); |
| reader = Entry.newBuilder() |
| .setLogSegmentInfo(metadata.getLogSegmentSequenceNumber(), |
| metadata.getStartSequenceId()) |
| .setEntryId(entry.getEntryId()) |
| .setEnvelopeEntry( |
| LogSegmentMetadata.supportsEnvelopedEntries(metadata.getVersion())) |
| .deserializeRecordSet(true) |
| .setInputStream(entry.getEntryInputStream()) |
| .buildReader(); |
| } |
| return nextKeyValue(); |
| } catch (BKException e) { |
| throw new IOException(e); |
| } |
| } |
| |
| @Override |
| public DLSN getCurrentKey() |
| throws IOException, InterruptedException { |
| return currentRecord.getDlsn(); |
| } |
| |
| @Override |
| public LogRecordWithDLSN getCurrentValue() |
| throws IOException, InterruptedException { |
| return currentRecord; |
| } |
| |
| @Override |
| public float getProgress() |
| throws IOException, InterruptedException { |
| if (metadata.getRecordCount() > 0) { |
| return ((float) (readPos + 1)) / metadata.getRecordCount(); |
| } |
| return 1; |
| } |
| |
| @Override |
| public void close() throws IOException { |
| try { |
| lh.close(); |
| } catch (InterruptedException e) { |
| Thread.currentThread().interrupt(); |
| throw new IOException(e); |
| } catch (BKException e) { |
| throw new IOException(e); |
| } |
| } |
| } |