Module io.netty5.codec

Package io.netty5.handler.codec.compression

Class LzmaCompressor

java.lang.Object

io.netty5.handler.codec.compression.LzmaCompressor

All Implemented Interfaces:

Compressor, AutoCloseable

public final class LzmaCompressor
extends Object
implements Compressor

Compresses a Buffer using the LZMA algorithm. See LZMA and LZMA format or documents in LZMA SDK archive.

Method Summary

Modifier and Type	Method	Description
void	close()	# Close the compressor.
Buffer	compress(Buffer in, BufferAllocator allocator)	This method will read from the input Buffer and compress into a new Buffer that will be allocated (if needed) from the BufferAllocator.
Buffer	finish(BufferAllocator allocator)	By calling this method we signal that the compression stream is marked as finish.
boolean	isClosed()	Return true if the decompressor was closed, false otherwise.
boolean	isFinished()	Returns true if the compressor was finished or closed.
static Supplier<LzmaCompressor>	newFactory()	Creates LZMA compressor factory with default settings.
static Supplier<LzmaCompressor>	newFactory(int dictionarySize)	Creates LZMA compressor factory with specified dictionary size and default values of lc = 3, lp = 0, pb = 2.
static Supplier<LzmaCompressor>	newFactory(int lc, int lp, int pb)	Creates LZMA compressor factory with specified lc, lp, pb values and the medium dictionary size of 65536.
static Supplier<LzmaCompressor>	newFactory(int lc, int lp, int pb, int dictionarySize)	Creates LZMA compressor factory with specified lc, lp, pb values and custom dictionary size.
static Supplier<LzmaCompressor>	newFactory(int lc, int lp, int pb, int dictionarySize, boolean endMarkerMode, int numFastBytes)	Creates LZMA compressor factory with specified settings.

Methods inherited from class java.lang.Object

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

Method Detail

newFactory

public static Supplier<LzmaCompressor> newFactory()

Creates LZMA compressor factory with default settings.

Returns:

the factory.

newFactory

public static Supplier<LzmaCompressor> newFactory(int lc,
                                                  int lp,
                                                  int pb)

Creates LZMA compressor factory with specified lc, lp, pb values and the medium dictionary size of 65536.

Returns:

the factory.

newFactory

public static Supplier<LzmaCompressor> newFactory(int dictionarySize)

Creates LZMA compressor factory with specified dictionary size and default values of lc = 3, lp = 0, pb = 2.

Returns:

the factory.

newFactory

public static Supplier<LzmaCompressor> newFactory(int lc,
                                                  int lp,
                                                  int pb,
                                                  int dictionarySize)

Creates LZMA compressor factory with specified lc, lp, pb values and custom dictionary size.

Returns:

the factory.

newFactory

public static Supplier<LzmaCompressor> newFactory(int lc,
                                                  int lp,
                                                  int pb,
                                                  int dictionarySize,
                                                  boolean endMarkerMode,
                                                  int numFastBytes)

Creates LZMA compressor factory with specified settings.

Parameters:

lc - the number of "literal context" bits, available values [0, 8], default value 3.

lp - the number of "literal position" bits, available values [0, 4], default value 0.

pb - the number of "position" bits, available values [0, 4], default value 2.

dictionarySize - available values [0, Integer.MAX_VALUE], default value is 65536.

endMarkerMode - indicates should LzmaCompressor use end of stream marker or not. Note, that LzmaCompressor always sets size of uncompressed data in LZMA header, so EOS marker is unnecessary. But you may use it for better portability. For full description see "LZMA Decoding modes" section of LZMA-Specification.txt in official LZMA SDK.

numFastBytes - available values [5, 273].

Returns:

the factory.

compress

public Buffer compress(Buffer in,
                       BufferAllocator allocator)
                throws CompressionException

Description copied from interface: Compressor

This method will read from the input Buffer and compress into a new Buffer that will be allocated (if needed) from the BufferAllocator. This method is expected to consume all data from the input but not take ownership. The caller is responsible to release the input buffer after this method returns.

Specified by:

compress in interface Compressor

Parameters:

in - the Buffer that contains the data to be compressed.

allocator - the BufferAllocator that is used to allocate a new buffer (if needed) to write the compressed bytes too.

Returns:

the Buffer that contains the compressed data. The caller of this method takes ownership of the buffer. The return value will never be null.

Throws:

CompressionException - thrown if an compression error was encountered or the compressor was closed already.

finish

public Buffer finish(BufferAllocator allocator)

Description copied from interface: Compressor

By calling this method we signal that the compression stream is marked as finish. The returned Buffer might contain a "trailer" which marks the end of the stream.

Specified by:

finish in interface Compressor

Returns:

the Buffer which represent the end of the compression stream, which might be empty if the compressor don't need a trailer to signal the end. The caller of this method takes ownership of the buffer. The return value will never be null.

isFinished

public boolean isFinished()

Description copied from interface: Compressor

Returns true if the compressor was finished or closed. This might happen because someone explicit called Compressor.finish(BufferAllocator) / Compressor.close() or the compressor implementation did decide to close itself due a compression error which can't be recovered. After Compressor.isFinished() returns true the Compressor.compress(Buffer, BufferAllocator) method will just return an empty buffer without consuming anything from its input buffer.

Specified by:

isFinished in interface Compressor

Returns:

true if the compressor was marked as finished, false otherwise.

isClosed

public boolean isClosed()

Description copied from interface: Compressor

Return true if the decompressor was closed, false otherwise.

Specified by:

isClosed in interface Compressor

Returns:

true if the decompressor was closed, false otherwise.

close

public void close()

Description copied from interface: Compressor

# Close the compressor. After this method was called Compressor.isFinished() will return true as well and it is not allowed to call Compressor.compress(Buffer, BufferAllocator) or Compressor.finish(BufferAllocator) anymore -

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Compressor