org.apache.hadoop.hive.ql.io.rcfile.merge.RCFileBlockMergeRecordReader Maven / Gradle / Ivy
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/**
* 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.rcfile.merge;
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;
import org.apache.hadoop.hive.ql.io.RCFile.Reader;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.RecordReader;
@SuppressWarnings("deprecation")
public class RCFileBlockMergeRecordReader implements
RecordReader {
private final Reader in;
private final long start;
private final long end;
private boolean more = true;
private final Path path;
protected Configuration conf;
public RCFileBlockMergeRecordReader(Configuration conf, FileSplit split)
throws IOException {
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 RCFileKeyBufferWrapper.class;
}
public Class getValueClass() {
return RCFileValueBufferWrapper.class;
}
public RCFileKeyBufferWrapper createKey() {
return new RCFileKeyBufferWrapper();
}
public RCFileValueBufferWrapper createValue() {
return new RCFileValueBufferWrapper();
}
@Override
public boolean next(RCFileKeyBufferWrapper key, RCFileValueBufferWrapper value)
throws IOException {
more = nextBlock(key, value);
return more;
}
protected boolean nextBlock(RCFileKeyBufferWrapper keyWrapper, RCFileValueBufferWrapper valueWrapper)
throws IOException {
if (!more) {
return false;
}
more = in.nextBlock();
if (!more) {
return false;
}
keyWrapper.keyBuffer = this.in.getCurrentKeyBufferObj();
keyWrapper.recordLength = this.in.getCurrentBlockLength();
keyWrapper.keyLength = this.in.getCurrentKeyLength();
keyWrapper.compressedKeyLength = this.in.getCurrentCompressedKeyLen();
keyWrapper.codec = this.in.getCompressionCodec();
keyWrapper.inputPath = path;
valueWrapper.valueBuffer = this.in.getCurrentValueBufferObj();
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 long getStart() {
return start;
}
public void close() throws IOException {
in.close();
}
}