org.apache.hadoop.io.compress

クラス BZip2Codec

java.lang.Object

org.apache.hadoop.io.compress.BZip2Codec

すべての実装されたインタフェース:

Configurable, CompressionCodec, SplittableCompressionCodec

@InterfaceAudience.Public
 @InterfaceStability.Evolving
public class BZip2Codec
extends Object
implements Configurable, SplittableCompressionCodec

This class provides output and input streams for bzip2 compression and decompression. It uses the native bzip2 library on the system if possible, else it uses a pure-Java implementation of the bzip2 algorithm. The configuration parameter io.compression.codec.bzip2.library can be used to control this behavior. In the pure-Java mode, the Compressor and Decompressor interfaces are not implemented. Therefore, in that mode, those methods of CompressionCodec which have a Compressor or Decompressor type argument, throw UnsupportedOperationException. Currently, support for splittability is available only in the pure-Java mode; therefore, if a SplitCompressionInputStream is requested, the pure-Java implementation is used, regardless of the setting of the configuration parameter mentioned above.

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
BZip2Codec() Creates a new instance of BZip2Codec.

メソッドのサマリー

修飾子とタイプ	メソッドと説明
Compressor	createCompressor() Create a new Compressor for use by this CompressionCodec.
Decompressor	createDecompressor() Create a new Decompressor for use by this CompressionCodec.
CompressionInputStream	createInputStream(InputStream in) Create a CompressionInputStream that will read from the given input stream and return a stream for uncompressed data.
CompressionInputStream	createInputStream(InputStream in, Decompressor decompressor) Create a CompressionInputStream that will read from the given InputStream with the given Decompressor, and return a stream for uncompressed data.
SplitCompressionInputStream	createInputStream(InputStream seekableIn, Decompressor decompressor, long start, long end, org.apache.hadoop.io.compress.SplittableCompressionCodec.READ_MODE readMode) Creates CompressionInputStream to be used to read off uncompressed data in one of the two reading modes. i.e.
CompressionOutputStream	createOutputStream(OutputStream out) Create a CompressionOutputStream that will write to the given OutputStream.
CompressionOutputStream	createOutputStream(OutputStream out, Compressor compressor) Create a CompressionOutputStream that will write to the given OutputStream with the given Compressor.
Class<? extends Compressor>	getCompressorType() Get the type of Compressor needed by this CompressionCodec.
Configuration	getConf() Return the configuration used by this object.
Class<? extends Decompressor>	getDecompressorType() Get the type of Decompressor needed by this CompressionCodec.
String	getDefaultExtension() .bz2 is recognized as the default extension for compressed BZip2 files
void	setConf(Configuration conf) Set the configuration to be used by this object.

クラスから継承されたメソッド java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

コンストラクタの詳細

BZip2Codec

public BZip2Codec()

Creates a new instance of BZip2Codec.

メソッドの詳細

setConf

public void setConf(Configuration conf)

Set the configuration to be used by this object.

定義:

setConf インタフェース内 Configurable

パラメータ:

conf - the configuration object.

getConf

public Configuration getConf()

Return the configuration used by this object.

定義:

getConf インタフェース内 Configurable

戻り値:

the configuration object used by this objec.

createOutputStream

public CompressionOutputStream createOutputStream(OutputStream out)
                                           throws IOException

Create a CompressionOutputStream that will write to the given OutputStream.

定義:

createOutputStream インタフェース内 CompressionCodec

パラメータ:

out - the location for the final output stream

戻り値:

a stream the user can write uncompressed data to, to have it compressed

例外:

IOException

createOutputStream

public CompressionOutputStream createOutputStream(OutputStream out,
                                                  Compressor compressor)
                                           throws IOException

Create a CompressionOutputStream that will write to the given OutputStream with the given Compressor.

定義:

createOutputStream インタフェース内 CompressionCodec

パラメータ:

out - the location for the final output stream

compressor - compressor to use

戻り値:

a stream the user can write uncompressed data to, to have it compressed

例外:

IOException

getCompressorType

public Class<? extends Compressor> getCompressorType()

Get the type of Compressor needed by this CompressionCodec.

定義:

getCompressorType インタフェース内 CompressionCodec

戻り値:

the type of compressor needed by this codec.

createCompressor

public Compressor createCompressor()

Create a new Compressor for use by this CompressionCodec.

定義:

createCompressor インタフェース内 CompressionCodec

戻り値:

a new compressor for use by this codec

createInputStream

public CompressionInputStream createInputStream(InputStream in)
                                         throws IOException

Create a CompressionInputStream that will read from the given input stream and return a stream for uncompressed data.

定義:

createInputStream インタフェース内 CompressionCodec

パラメータ:

in - the stream to read compressed bytes from

戻り値:

a stream to read uncompressed bytes from

例外:

IOException

createInputStream

public CompressionInputStream createInputStream(InputStream in,
                                                Decompressor decompressor)
                                         throws IOException

Create a CompressionInputStream that will read from the given InputStream with the given Decompressor, and return a stream for uncompressed data.

定義:

createInputStream インタフェース内 CompressionCodec

パラメータ:

in - the stream to read compressed bytes from

decompressor - decompressor to use

戻り値:

a stream to read uncompressed bytes from

例外:

IOException

createInputStream

public SplitCompressionInputStream createInputStream(InputStream seekableIn,
                                                     Decompressor decompressor,
                                                     long start,
                                                     long end,
                                                     org.apache.hadoop.io.compress.SplittableCompressionCodec.READ_MODE readMode)
                                              throws IOException

Creates CompressionInputStream to be used to read off uncompressed data in one of the two reading modes. i.e. Continuous or Blocked reading modes

定義:

createInputStream インタフェース内 SplittableCompressionCodec

パラメータ:

seekableIn - The InputStream

start - The start offset into the compressed stream

end - The end offset into the compressed stream

readMode - Controls whether progress is reported continuously or only at block boundaries.

戻り値:

CompressionInputStream for BZip2 aligned at block boundaries

例外:

IOException

getDecompressorType

public Class<? extends Decompressor> getDecompressorType()

Get the type of Decompressor needed by this CompressionCodec.

定義:

getDecompressorType インタフェース内 CompressionCodec

戻り値:

the type of decompressor needed by this codec.

createDecompressor

public Decompressor createDecompressor()

Create a new Decompressor for use by this CompressionCodec.

定義:

createDecompressor インタフェース内 CompressionCodec

戻り値:

a new decompressor for use by this codec

getDefaultExtension

public String getDefaultExtension()

.bz2 is recognized as the default extension for compressed BZip2 files

定義:

getDefaultExtension インタフェース内 CompressionCodec

戻り値:

A String telling the default bzip2 file extension