Module io.netty5.codec

Package io.netty5.handler.codec.compression

Class FastLzCompressor

java.lang.Object

io.netty5.handler.codec.compression.FastLzCompressor

All Implemented Interfaces:

Compressor, AutoCloseable

public final class FastLzCompressor
extends Object
implements Compressor

Compresses a Buffer using the FastLZ algorithm. See FastLZ format.

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<FastLzCompressor>	newFactory()	Creates a FastLZ compressor factory without checksum calculator and with auto detection of compression level.
static Supplier<FastLzCompressor>	newFactory(boolean validateChecksums)	Creates a FastLZ compressor factory with auto detection of compression level and calculation of checksums as specified.
static Supplier<FastLzCompressor>	newFactory(int level)	Creates a FastLZ compressor factory with specified compression level and without checksum calculator.
static Supplier<FastLzCompressor>	newFactory(int level, Checksum checksum)	Creates a FastLZ compressor factory with specified compression level and checksum calculator.

Methods inherited from class java.lang.Object

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

Method Detail

newFactory

public static Supplier<FastLzCompressor> newFactory()

Creates a FastLZ compressor factory without checksum calculator and with auto detection of compression level.

Returns:

the factory.

newFactory

public static Supplier<FastLzCompressor> newFactory(int level)

Creates a FastLZ compressor factory with specified compression level and without checksum calculator.

Parameters:

level - supports only these values: 0 - Encoder will choose level automatically depending on the length of the input buffer. 1 - Level 1 is the fastest compression and generally useful for short data. 2 - Level 2 is slightly slower but it gives better compression ratio.

Returns:

the factory.

newFactory

public static Supplier<FastLzCompressor> newFactory(boolean validateChecksums)

Creates a FastLZ compressor factory with auto detection of compression level and calculation of checksums as specified.

Parameters:

validateChecksums - If true, the checksum of each block will be calculated and this value will be added to the header of block. By default FastLzCompressor uses Adler32 for checksum calculation.

Returns:

the factory.

newFactory

public static Supplier<FastLzCompressor> newFactory(int level,
                                                    Checksum checksum)

Creates a FastLZ compressor factory with specified compression level and checksum calculator.

Parameters:

level - supports only these values: 0 - Encoder will choose level automatically depending on the length of the input buffer. 1 - Level 1 is the fastest compression and generally useful for short data. 2 - Level 2 is slightly slower but it gives better compression ratio.

checksum - the Checksum instance to use to check data for integrity. You may set null if you don't want to validate checksum of each block.

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