Netty/Codec 4.1.107.Final · io.netty.handler.codec.compression.Bzip2BlockCompressor

Compresses and writes a single Bzip2 block.

Block encoding consists of the following stages:
1. Run-Length Encoding[1] - write(int)
2. Burrows Wheeler Transform - close(ByteBuf) (through Bzip2DivSufSort)
3. Write block header - close(ByteBuf)
4. Move To Front Transform - close(ByteBuf) (through Bzip2HuffmanStageEncoder)
5. Run-Length Encoding[2] - close(ByteBuf) (through Bzip2HuffmanStageEncoder)
6. Create and write Huffman tables - close(ByteBuf) (through Bzip2HuffmanStageEncoder)
7. Huffman encode and write data - close(ByteBuf) (through Bzip2HuffmanStageEncoder)

Field Summary

Modifier and Type	Field and Description
private final byte[]	block The RLE'd block data.
private int	blockLength Current length of the data within the `block` array.
private final int	blockLengthLimit A limit beyond which new data will not be accepted into the block.
private final boolean[]	blockValuesPresent The values that are present within the RLE'd block data.
private final int[]	bwtBlock The Burrows Wheeler Transformed block data.
private final Crc32	crc CRC builder for the block.
private int	rleCurrentValue The current RLE value being accumulated (undefined when `rleLength` is 0).
private int	rleLength The repeat count of the current RLE value.
private final ByteProcessor	writeProcessor
private final Bzip2BitWriter	writer A writer that provides bit-level writes.

Constructor Summary

Access	Constructor and Description
pack-priv	Bzip2BlockCompressor(final Bzip2BitWriter The `Bzip2BitWriter` which provides bit-level writes writer, final int The declared block size in bytes. Up to this many bytes will be accepted into the block after Run-Length Encoding is applied blockSize)

Method Summary

Modifier and Type	Method and Description
pack-priv int	Returns: Number of available bytes which can be written availableSize() Gets available size of the current block.
pack-priv void	close(ByteBuf out) Compresses and writes out the block.
pack-priv int	Returns: The block's CRC crc() Gets the CRC of the completed block.
pack-priv boolean	Returns: `true` if one or more bytes has been written to the block, otherwise `false` isEmpty() Determines if any bytes have been written to the block.
pack-priv boolean	Returns: `true` if the block is full, otherwise `false` isFull() Determines if the block is full and ready for compression.
pack-priv boolean	Returns: `true` if the byte was written, or `false` if the block is already full write(final int The byte to write value) Writes a byte to the block, accumulating to an RLE run where possible.
pack-priv int	Returns: The actual number of input bytes written. May be less than the number requested, or zero if the block is already full write(final ByteBuf The buffer to write buffer, int The offset within the input data to write from offset, int The number of bytes of input data to write length) Writes an array to the block.
private void	writeRun(final int The value to write value, int The run length of the value to write runLength) Writes an RLE run to the block array, updating the block CRC and present values array as required.
private void	writeSymbolMap(ByteBuf out) Write the Huffman symbol to output byte map.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

block	back to summary
private final byte[] block The RLE'd block data.

blockLength	back to summary
private int blockLength Current length of the data within the `block` array.

blockLengthLimit	back to summary
private final int blockLengthLimit A limit beyond which new data will not be accepted into the block.

blockValuesPresent	back to summary
private final boolean[] blockValuesPresent The values that are present within the RLE'd block data. For each index, `true` if that value is present within the data, otherwise `false`.

bwtBlock	back to summary
private final int[] bwtBlock The Burrows Wheeler Transformed block data.

crc	back to summary
private final Crc32 crc CRC builder for the block.

rleCurrentValue	back to summary
private int rleCurrentValue The current RLE value being accumulated (undefined when `rleLength` is 0).

rleLength	back to summary
private int rleLength The repeat count of the current RLE value.

writeProcessor	back to summary
private final ByteProcessor writeProcessor

writer	back to summary
private final Bzip2BitWriter writer A writer that provides bit-level writes.

Constructor Detail

Bzip2BlockCompressor	back to summary
pack-priv Bzip2BlockCompressor(final Bzip2BitWriter writer, final int blockSize) Parameters writer:Bzip2BitWriter The `Bzip2BitWriter` which provides bit-level writes blockSize:int The declared block size in bytes. Up to this many bytes will be accepted into the block after Run-Length Encoding is applied

Method Detail

availableSize	back to summary
pack-priv int availableSize() Gets available size of the current block. Returns:int Number of available bytes which can be written

availableSize

back to summary

pack-priv int availableSize()

Gets available size of the current block.

Returns:int: Number of available bytes which can be written

close	back to summary
pack-priv void close(ByteBuf out) Compresses and writes out the block.

crc back to summary

crc	back to summary
pack-priv int crc() Gets the CRC of the completed block. Only valid after calling `close(ByteBuf)`. Returns:int The block's CRC

pack-priv int crc()

Gets the CRC of the completed block. Only valid after calling close(ByteBuf).

Returns:int: The block's CRC

isEmpty back to summary

isEmpty	back to summary
pack-priv boolean isEmpty() Determines if any bytes have been written to the block. Returns:boolean `true` if one or more bytes has been written to the block, otherwise `false`

pack-priv boolean isEmpty()

Determines if any bytes have been written to the block.

Returns:boolean: true if one or more bytes has been written to the block, otherwise false

isFull back to summary

isFull	back to summary
pack-priv boolean isFull() Determines if the block is full and ready for compression. Returns:boolean `true` if the block is full, otherwise `false`

pack-priv boolean isFull()

Determines if the block is full and ready for compression.

Returns:boolean: true if the block is full, otherwise false

write back to summary

write	back to summary
pack-priv boolean write(final int value) Writes a byte to the block, accumulating to an RLE run where possible. Parameters value:int The byte to write Returns:boolean `true` if the byte was written, or `false` if the block is already full

pack-priv boolean write(final int value)

Writes a byte to the block, accumulating to an RLE run where possible.

Parameters

value:int: The byte to write

Returns:boolean

true if the byte was written, or false if the block is already full

write	back to summary
pack-priv int write(final ByteBuf buffer, int offset, int length) Writes an array to the block. Parameters buffer:ByteBuf The buffer to write offset:int The offset within the input data to write from length:int The number of bytes of input data to write Returns:int The actual number of input bytes written. May be less than the number requested, or zero if the block is already full

write

back to summary

pack-priv int write(final ByteBuf buffer, int offset, int length)

Writes an array to the block.

Parameters

buffer:ByteBuf: The buffer to write
offset:int: The offset within the input data to write from
length:int: The number of bytes of input data to write

Returns:int

The actual number of input bytes written. May be less than the number requested, or zero if the block is already full

writeRun	back to summary
private void writeRun(final int value, int runLength) Writes an RLE run to the block array, updating the block CRC and present values array as required. Parameters value:int The value to write runLength:int The run length of the value to write

writeRun

back to summary

private void writeRun(final int value, int runLength)

Writes an RLE run to the block array, updating the block CRC and present values array as required.

Parameters

value:int: The value to write
runLength:int: The run length of the value to write

writeSymbolMap	back to summary
private void writeSymbolMap(ByteBuf out) Write the Huffman symbol to output byte map.

pack-priv final Class Bzip2BlockCompressor

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail