com.github.luben.zstd

Class ZstdCompressCtx

java.lang.Object

com.github.luben.zstd.ZstdCompressCtx

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class ZstdCompressCtx
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
ZstdCompressCtx() Create a context for faster compress operations One such context is required for each thread - put this in a ThreadLocal.

Method Summary

Modifier and Type	Method and Description
void	close()
long	compressDirectByteBuffer(java.nio.ByteBuffer dstBuff, int dstOffset, int dstSize, java.nio.ByteBuffer srcBuff, int srcOffset, int srcSize) Compresses buffer 'srcBuff' into buffer 'dstBuff' reusing this ZstdCompressCtx.
protected void	finalize()
void	loadDict(byte[] dict) Load compression dictionary to be used for subsequently compressed frames.
void	loadDict(ZstdDictCompress dict) Load compression dictionary to be used for subsequently compressed frames.
void	setChecksum(boolean checksumFlag) Enable or disable compression checksums
void	setContentSize(boolean contentSizeFlag) Enable or disable content size
void	setDictID(boolean dictIDFlag) Enable or disable dictID
void	setFinalize(boolean finalize) Enable or disable class finalizers If finalizers are disabled the responsibility fir calling the `close` method is on the consumer.
void	setLevel(int level) Set compression level

Methods inherited from class java.lang.Object

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

Constructor Detail

ZstdCompressCtx

public ZstdCompressCtx()

Create a context for faster compress operations One such context is required for each thread - put this in a ThreadLocal.

Method Detail

setLevel

public void setLevel(int level)

Set compression level

Parameters:

level - compression level, default: 3

setChecksum

public void setChecksum(boolean checksumFlag)

Enable or disable compression checksums

Parameters:

checksumFlag - A 32-bits checksum of content is written at end of frame, default: false

setContentSize

public void setContentSize(boolean contentSizeFlag)

Enable or disable content size

Parameters:

contentSizeFlag - Content size will be written into frame header _whenever known_, default: true

setDictID

public void setDictID(boolean dictIDFlag)

Enable or disable dictID

Parameters:

dictIDFlag - When applicable, dictionary's ID is written into frame header, default: true

loadDict

public void loadDict(ZstdDictCompress dict)

Load compression dictionary to be used for subsequently compressed frames.

Parameters:

dict - the dictionary or `null` to remove loaded dictionary

loadDict

public void loadDict(byte[] dict)

Load compression dictionary to be used for subsequently compressed frames.

Parameters:

dict - the dictionary or `null` to remove loaded dictionary

compressDirectByteBuffer

public long compressDirectByteBuffer(java.nio.ByteBuffer dstBuff,
                                     int dstOffset,
                                     int dstSize,
                                     java.nio.ByteBuffer srcBuff,
                                     int srcOffset,
                                     int srcSize)

Compresses buffer 'srcBuff' into buffer 'dstBuff' reusing this ZstdCompressCtx. Destination buffer should be sized to handle worst cases situations (input data not compressible). Worst case size evaluation is provided by function ZSTD_compressBound(). Note: compression level and parameters are

Parameters:

dstBuff - the destination buffer - must be direct

dstOffset - the start offset of 'dstBuff'

dstSize - the size of 'dstBuff'

srcBuff - the source buffer - must be direct

srcOffset - the start offset of 'srcBuff'

srcSize - the length of 'srcBuff'

Returns:

the number of bytes written into buffer 'dstBuff'.

setFinalize

public void setFinalize(boolean finalize)

Enable or disable class finalizers If finalizers are disabled the responsibility fir calling the `close` method is on the consumer.

Parameters:

finalize, - default `true` - finalizers are enabled

close

public void close()

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

finalize

protected void finalize()

Overrides:

finalize in class java.lang.Object