/**
* 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.hadoop.hive.ql.io;
import java.io.IOException;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedBatchUtil;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedRowBatch;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedRowBatchCtx;
import org.apache.hadoop.hive.ql.io.RCFile.KeyBuffer;
import org.apache.hadoop.hive.ql.io.RCFile.Reader;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.serde2.columnar.BytesRefArrayWritable;
import org.apache.hadoop.io.DataOutputBuffer;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.RecordReader;
/**
* RCFileRecordReader.
*/
public class VectorizedRCFileRecordReader implements RecordReader<NullWritable, VectorizedRowBatch> {
private final Reader in;
private final long start;
private final long end;
private boolean more = true;
protected Configuration conf;
private final FileSplit split;
private final boolean useCache;
private VectorizedRowBatchCtx rbCtx;
private final LongWritable keyCache = new LongWritable();
private final BytesRefArrayWritable colsCache = new BytesRefArrayWritable();
private boolean addPartitionCols = true;
private final DataOutputBuffer buffer = new DataOutputBuffer();
private static RCFileSyncCache syncCache = new RCFileSyncCache();
private static final class RCFileSyncEntry {
long end;
long endSync;
}
private static final class RCFileSyncCache {
private final Map<String, RCFileSyncEntry> cache;
public RCFileSyncCache() {
cache = Collections.synchronizedMap(new WeakHashMap<String, RCFileSyncEntry>());
}
public void put(FileSplit split, long endSync) {
Path path = split.getPath();
long end = split.getStart() + split.getLength();
String key = path.toString() + "+" + String.format("%d", end);
RCFileSyncEntry entry = new RCFileSyncEntry();
entry.end = end;
entry.endSync = endSync;
if (entry.endSync >= entry.end) {
cache.put(key, entry);
}
}
public long get(FileSplit split) {
Path path = split.getPath();
long start = split.getStart();
String key = path.toString() + "+" + String.format("%d", start);
RCFileSyncEntry entry = cache.get(key);
if (entry != null) {
return entry.endSync;
}
return -1;
}
}
public VectorizedRCFileRecordReader(Configuration conf, FileSplit split)
throws IOException {
Path path = split.getPath();
FileSystem fs = path.getFileSystem(conf);
this.in = new RCFile.Reader(fs, path, conf);
this.end = split.getStart() + split.getLength();
this.conf = conf;
this.split = split;
useCache = HiveConf.getBoolVar(conf, HiveConf.ConfVars.HIVEUSERCFILESYNCCACHE);
if (split.getStart() > in.getPosition()) {
long oldSync = useCache ? syncCache.get(split) : -1;
if (oldSync == -1) {
in.sync(split.getStart()); // sync to start
} else {
in.seek(oldSync);
}
}
this.start = in.getPosition();
more = start < end;
try {
rbCtx = new VectorizedRowBatchCtx();
rbCtx.init(conf, split);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public Class<?> getKeyClass() {
return LongWritable.class;
}
public Class<?> getValueClass() {
return BytesRefArrayWritable.class;
}
@Override
public NullWritable createKey() {
return NullWritable.get();
}
@Override
public VectorizedRowBatch createValue() {
VectorizedRowBatch result = null;
try {
result = rbCtx.createVectorizedRowBatch();
} catch (HiveException e) {
new RuntimeException("Error creating a batch", e);
}
return result;
}
public boolean nextBlock() throws IOException {
return in.nextBlock();
}
@Override
public boolean next(NullWritable key, VectorizedRowBatch value) throws IOException {
// Reset column fields noNull values to true
VectorizedBatchUtil.setNoNullFields(value);
buffer.reset();
value.selectedInUse = false;
for (int i = 0; i < value.numCols; i++) {
value.cols[i].isRepeating = false;
}
int i = 0;
try {
for (; i < VectorizedRowBatch.DEFAULT_SIZE; i++) {
more = next(keyCache);
if (more) {
// Check and update partition cols if necessary. Ideally this should be done
// in CreateValue() as the partition is constant per split. But since Hive uses
// CombineHiveRecordReader and as this does not call CreateValue() for
// each new RecordReader it creates, this check is required in next()
if (addPartitionCols) {
rbCtx.addPartitionColsToBatch(value);
addPartitionCols = false;
}
in.getCurrentRow(colsCache);
// Currently RCFile reader does not support reading vectorized
// data. Populating the batch by adding one row at a time.
rbCtx.addRowToBatch(i, (Writable) colsCache, value, buffer);
} else {
break;
}
}
} catch (Exception e) {
new RuntimeException("Error while getting next row", e);
}
value.size = i;
return more;
}
protected boolean next(LongWritable key) throws IOException {
if (!more) {
return false;
}
more = in.next(key);
long lastSeenSyncPos = in.lastSeenSyncPos();
if (lastSeenSyncPos >= end) {
if (useCache) {
syncCache.put(split, lastSeenSyncPos);
}
more = false;
return more;
}
return more;
}
/**
* Return the progress within the input split.
*
* @return 0.0 to 1.0 of the input byte range
*/
public float getProgress() throws IOException {
if (end == start) {
return 0.0f;
} else {
return Math.min(1.0f, (in.getPosition() - start) / (float) (end - start));
}
}
public long getPos() throws IOException {
return in.getPosition();
}
public KeyBuffer getKeyBuffer() {
return in.getCurrentKeyBufferObj();
}
protected void seek(long pos) throws IOException {
in.seek(pos);
}
public void sync(long pos) throws IOException {
in.sync(pos);
}
public void resetBuffer() {
in.resetBuffer();
}
public long getStart() {
return start;
}
public void close() throws IOException {
in.close();
}
}