/*
* 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.io.compress.bzip2;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CommonConfigurationKeys;
import org.apache.hadoop.util.NativeCodeLoader;
import org.apache.hadoop.io.compress.Compressor;
import org.apache.hadoop.io.compress.Decompressor;
import org.apache.hadoop.io.compress.bzip2.Bzip2Compressor;
import org.apache.hadoop.io.compress.bzip2.Bzip2Decompressor;
import org.apache.hadoop.io.compress.bzip2.BZip2DummyCompressor;
import org.apache.hadoop.io.compress.bzip2.BZip2DummyDecompressor;
/**
* A collection of factories to create the right
* bzip2 compressor/decompressor instances.
*
*/
public class Bzip2Factory {
private static final Log LOG = LogFactory.getLog(Bzip2Factory.class);
private static String bzip2LibraryName = "";
private static boolean nativeBzip2Loaded;
/**
* Check if native-bzip2 code is loaded & initialized correctly and
* can be loaded for this job.
*
* @param conf configuration
* @return <code>true</code> if native-bzip2 is loaded & initialized
* and can be loaded for this job, else <code>false</code>
*/
public static boolean isNativeBzip2Loaded(Configuration conf) {
String libname = conf.get("io.compression.codec.bzip2.library",
"system-native");
if (!bzip2LibraryName.equals(libname)) {
nativeBzip2Loaded = false;
bzip2LibraryName = libname;
if (libname.equals("java-builtin")) {
LOG.info("Using pure-Java version of bzip2 library");
} else if (conf.getBoolean(
CommonConfigurationKeys.IO_NATIVE_LIB_AVAILABLE_KEY,
CommonConfigurationKeys.IO_NATIVE_LIB_AVAILABLE_DEFAULT) &&
NativeCodeLoader.isNativeCodeLoaded()) {
try {
// Initialize the native library.
Bzip2Compressor.initSymbols(libname);
Bzip2Decompressor.initSymbols(libname);
nativeBzip2Loaded = true;
LOG.info("Successfully loaded & initialized native-bzip2 library " +
libname);
} catch (Throwable t) {
LOG.warn("Failed to load/initialize native-bzip2 library " +
libname + ", will use pure-Java version");
}
}
}
return nativeBzip2Loaded;
}
/**
* Return the appropriate type of the bzip2 compressor.
*
* @param conf configuration
* @return the appropriate type of the bzip2 compressor.
*/
public static Class<? extends Compressor>
getBzip2CompressorType(Configuration conf) {
return isNativeBzip2Loaded(conf) ?
Bzip2Compressor.class : BZip2DummyCompressor.class;
}
/**
* Return the appropriate implementation of the bzip2 compressor.
*
* @param conf configuration
* @return the appropriate implementation of the bzip2 compressor.
*/
public static Compressor getBzip2Compressor(Configuration conf) {
return isNativeBzip2Loaded(conf)?
new Bzip2Compressor(conf) : new BZip2DummyCompressor();
}
/**
* Return the appropriate type of the bzip2 decompressor.
*
* @param conf configuration
* @return the appropriate type of the bzip2 decompressor.
*/
public static Class<? extends Decompressor>
getBzip2DecompressorType(Configuration conf) {
return isNativeBzip2Loaded(conf) ?
Bzip2Decompressor.class : BZip2DummyDecompressor.class;
}
/**
* Return the appropriate implementation of the bzip2 decompressor.
*
* @param conf configuration
* @return the appropriate implementation of the bzip2 decompressor.
*/
public static Decompressor getBzip2Decompressor(Configuration conf) {
return isNativeBzip2Loaded(conf) ?
new Bzip2Decompressor() : new BZip2DummyDecompressor();
}
public static void setBlockSize(Configuration conf, int blockSize) {
conf.setInt("bzip2.compress.blocksize", blockSize);
}
public static int getBlockSize(Configuration conf) {
return conf.getInt("bzip2.compress.blocksize",
Bzip2Compressor.DEFAULT_BLOCK_SIZE);
}
public static void setWorkFactor(Configuration conf, int workFactor) {
conf.setInt("bzip2.compress.workfactor", workFactor);
}
public static int getWorkFactor(Configuration conf) {
return conf.getInt("bzip2.compress.workfactor",
Bzip2Compressor.DEFAULT_WORK_FACTOR);
}
}