/**
* 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 org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hive.ql.io.RCFile.Reader;
import org.apache.hadoop.hive.serde2.columnar.BytesRefArrayWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.RecordReader;
import org.apache.hadoop.util.ReflectionUtils;
/**
* RCFileRecordReader.
*
* @param <K>
* @param <V>
*/
public class RCFileRecordReader<K extends LongWritable, V extends BytesRefArrayWritable>
implements RecordReader<LongWritable, BytesRefArrayWritable> {
private final Reader in;
private final long start;
private final long end;
private boolean more = true;
protected Configuration conf;
public RCFileRecordReader(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;
if (split.getStart() > in.getPosition()) {
in.sync(split.getStart()); // sync to start
}
this.start = in.getPosition();
more = start < end;
}
public Class<?> getKeyClass() {
return LongWritable.class;
}
public Class<?> getValueClass() {
return BytesRefArrayWritable.class;
}
public LongWritable createKey() {
return (LongWritable) ReflectionUtils.newInstance(getKeyClass(), conf);
}
public BytesRefArrayWritable createValue() {
return (BytesRefArrayWritable) ReflectionUtils.newInstance(getValueClass(),
conf);
}
@Override
public boolean next(LongWritable key, BytesRefArrayWritable value)
throws IOException {
more = next(key);
if (more) {
in.getCurrentRow(value);
}
return more;
}
protected boolean next(LongWritable key) throws IOException {
if (!more) {
return false;
}
more = in.next(key);
if (!more) {
return false;
}
long lastSeenSyncPos = in.lastSeenSyncPos();
if (lastSeenSyncPos >= end) {
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();
}
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();
}
}