/**
* 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.shims;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.EnumSet;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.ReadOption;
import org.apache.hadoop.hive.shims.HadoopShims.DirectCompressionType;
import org.apache.hadoop.hive.shims.HadoopShims.DirectDecompressorShim;
import org.apache.hadoop.io.ByteBufferPool;
import org.apache.hadoop.io.compress.DirectDecompressor;
import org.apache.hadoop.io.compress.snappy.SnappyDecompressor.SnappyDirectDecompressor;
import org.apache.hadoop.io.compress.zlib.ZlibDecompressor.CompressionHeader;
import org.apache.hadoop.io.compress.zlib.ZlibDecompressor.ZlibDirectDecompressor;
import org.apache.hadoop.hive.shims.HadoopShims.ByteBufferPoolShim;
import org.apache.hadoop.hive.shims.HadoopShims.ZeroCopyReaderShim;
class ZeroCopyShims {
private static final class ByteBufferPoolAdapter implements ByteBufferPool {
private ByteBufferPoolShim pool;
public ByteBufferPoolAdapter(ByteBufferPoolShim pool) {
this.pool = pool;
}
@Override
public final ByteBuffer getBuffer(boolean direct, int length) {
return this.pool.getBuffer(direct, length);
}
@Override
public final void putBuffer(ByteBuffer buffer) {
this.pool.putBuffer(buffer);
}
}
private static final class ZeroCopyAdapter implements ZeroCopyReaderShim {
private final FSDataInputStream in;
private final ByteBufferPoolAdapter pool;
private final static EnumSet<ReadOption> CHECK_SUM = EnumSet
.noneOf(ReadOption.class);
private final static EnumSet<ReadOption> NO_CHECK_SUM = EnumSet
.of(ReadOption.SKIP_CHECKSUMS);
public ZeroCopyAdapter(FSDataInputStream in, ByteBufferPoolShim poolshim) {
this.in = in;
if (poolshim != null) {
pool = new ByteBufferPoolAdapter(poolshim);
} else {
pool = null;
}
}
public final ByteBuffer readBuffer(int maxLength, boolean verifyChecksums)
throws IOException {
EnumSet<ReadOption> options = NO_CHECK_SUM;
if (verifyChecksums) {
options = CHECK_SUM;
}
return this.in.read(this.pool, maxLength, options);
}
public final void releaseBuffer(ByteBuffer buffer) {
this.in.releaseBuffer(buffer);
}
}
public static ZeroCopyReaderShim getZeroCopyReader(FSDataInputStream in,
ByteBufferPoolShim pool) throws IOException {
return new ZeroCopyAdapter(in, pool);
}
private static final class DirectDecompressorAdapter implements
DirectDecompressorShim {
private final DirectDecompressor decompressor;
public DirectDecompressorAdapter(DirectDecompressor decompressor) {
this.decompressor = decompressor;
}
public void decompress(ByteBuffer src, ByteBuffer dst) throws IOException {
this.decompressor.decompress(src, dst);
}
}
public static DirectDecompressorShim getDirectDecompressor(
DirectCompressionType codec) {
DirectDecompressor decompressor = null;
switch (codec) {
case ZLIB: {
decompressor = new ZlibDirectDecompressor();
}
break;
case ZLIB_NOHEADER: {
decompressor = new ZlibDirectDecompressor(CompressionHeader.NO_HEADER, 0);
}
break;
case SNAPPY: {
decompressor = new SnappyDirectDecompressor();
}
break;
}
if (decompressor != null) {
return new DirectDecompressorAdapter(decompressor);
}
/* not supported */
return null;
}
}