org.apache.hadoop.io.compress

クラス BlockCompressorStream

java.lang.Object

java.io.OutputStream

org.apache.hadoop.io.compress.CompressionOutputStream

org.apache.hadoop.io.compress.CompressorStream

org.apache.hadoop.io.compress.BlockCompressorStream

すべての実装されたインタフェース:

Closeable, Flushable, AutoCloseable

@InterfaceAudience.Public
 @InterfaceStability.Evolving
public class BlockCompressorStream
extends CompressorStream

A CompressorStream which works with 'block-based' based compression algorithms, as opposed to 'stream-based' compression algorithms. It should be noted that this wrapper does not guarantee that blocks will be sized for the compressor. If the Compressor requires buffering to effect meaningful compression, it is responsible for it.

フィールドのサマリー

クラスから継承されたフィールド org.apache.hadoop.io.compress.CompressorStream

buffer, closed, compressor

クラスから継承されたフィールド org.apache.hadoop.io.compress.CompressionOutputStream

out

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
BlockCompressorStream(OutputStream out, Compressor compressor) Create a BlockCompressorStream with given output-stream and compressor.
BlockCompressorStream(OutputStream out, Compressor compressor, int bufferSize, int compressionOverhead) Create a BlockCompressorStream.

メソッドのサマリー

修飾子とタイプ	メソッドと説明
protected void	compress()
void	finish() Finishes writing compressed data to the output stream without closing the underlying stream.
void	write(byte[] b, int off, int len) Write the data provided to the compression codec, compressing no more than the buffer size less the compression overhead as specified during construction for each block.

クラスから継承されたメソッド org.apache.hadoop.io.compress.CompressorStream

close, resetState, write

クラスから継承されたメソッド org.apache.hadoop.io.compress.CompressionOutputStream

flush

クラスから継承されたメソッド java.io.OutputStream

write

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

BlockCompressorStream

public BlockCompressorStream(OutputStream out,
                             Compressor compressor,
                             int bufferSize,
                             int compressionOverhead)

Create a BlockCompressorStream.

パラメータ:

out - stream

compressor - compressor to be used

bufferSize - size of buffer

compressionOverhead - maximum 'overhead' of the compression algorithm with given bufferSize

BlockCompressorStream

public BlockCompressorStream(OutputStream out,
                             Compressor compressor)

Create a BlockCompressorStream with given output-stream and compressor. Use default of 512 as bufferSize and compressionOverhead of (1% of bufferSize + 12 bytes) = 18 bytes (zlib algorithm).

パラメータ:

out - stream

compressor - compressor to be used

メソッドの詳細

write

public void write(byte[] b,
                  int off,
                  int len)
           throws IOException

Write the data provided to the compression codec, compressing no more than the buffer size less the compression overhead as specified during construction for each block. Each block contains the uncompressed length for the block, followed by one or more length-prefixed blocks of compressed data.

オーバーライド:

write クラス内 CompressorStream

例外:

IOException

finish

public void finish()
            throws IOException

クラスからコピーされた説明: CompressionOutputStream

Finishes writing compressed data to the output stream without closing the underlying stream.

オーバーライド:

finish クラス内 CompressorStream

例外:

IOException

compress

protected void compress()
                 throws IOException

オーバーライド:

compress クラス内 CompressorStream

例外:

IOException