Package com.github.luben.zstd

Class ZstdDecompressCtx

java.lang.Object

com.github.luben.zstd.AutoCloseBase

com.github.luben.zstd.ZstdDecompressCtx

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class ZstdDecompressCtx
extends AutoCloseBase

Field Summary

Fields

Modifier and Type	Field	Description
private ZstdDictDecompress	decompression_dict
private long	nativePtr

Constructor Summary

Constructors

Constructor	Description
ZstdDecompressCtx()	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	Description
int	decompress(byte[] dst, byte[] src)
byte[]	decompress(byte[] src, int originalSize)	Decompress data
java.nio.ByteBuffer	decompress(java.nio.ByteBuffer srcBuf, int originalSize)
int	decompress(java.nio.ByteBuffer dstBuf, java.nio.ByteBuffer srcBuf)	Decompresses buffer 'srcBuff' into buffer 'dstBuff' using this ZstdDecompressCtx.
int	decompressByteArray(byte[] dstBuff, int dstOffset, int dstSize, byte[] srcBuff, int srcOffset, int srcSize)	Decompresses byte array 'srcBuff' into byte array 'dstBuff' using this ZstdDecompressCtx.
private static long	decompressByteArray0(long nativePtr, byte[] dst, int dstOffset, int dstSize, byte[] src, int srcOffset, int srcSize)
int	decompressDirectByteBuffer(java.nio.ByteBuffer dstBuff, int dstOffset, int dstSize, java.nio.ByteBuffer srcBuff, int srcOffset, int srcSize)	Decompresses buffer 'srcBuff' into buffer 'dstBuff' using this ZstdDecompressCtx.
private static long	decompressDirectByteBuffer0(long nativePtr, java.nio.ByteBuffer dst, int dstOffset, int dstSize, java.nio.ByteBuffer src, int srcOffset, int srcSize)
boolean	decompressDirectByteBufferStream(java.nio.ByteBuffer dst, java.nio.ByteBuffer src)	Decompress as much of the src ByteBuffer into the dst ByteBuffer as possible.
private static long	decompressDirectByteBufferStream0(long nativePtr, java.nio.ByteBuffer dst, int dstOffset, int dstSize, java.nio.ByteBuffer src, int srcOffset, int srcSize)	4 pieces of information are packed into the return value of this method, which must be treated as an unsigned long.
(package private) void	doClose()
private void	ensureOpen()
private static void	free(long nativePtr)
private static long	init()
private static long	loadDDict0(long nativePtr, byte[] dict)
private static long	loadDDictFast0(long nativePtr, ZstdDictDecompress dict)
ZstdDecompressCtx	loadDict(byte[] dict)	Load decompression dictionary.
ZstdDecompressCtx	loadDict(ZstdDictDecompress dict)	Load decompression dictionary
void	reset()	Clear all state and parameters from the decompression context.
private static void	reset0(long nativePtr)
ZstdDecompressCtx	setMagicless(boolean magiclessFlag)	Enable or disable magicless frames

Methods inherited from class com.github.luben.zstd.AutoCloseBase

acquireSharedLock, close, releaseSharedLock, storeFence

Methods inherited from class java.lang.Object

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

Field Detail

nativePtr

private long nativePtr

decompression_dict

private ZstdDictDecompress decompression_dict

Constructor Detail

ZstdDecompressCtx

public ZstdDecompressCtx()

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

Method Detail

init

private static long init()

free

private static void free(long nativePtr)

doClose

void doClose()

Specified by:

doClose in class AutoCloseBase

setMagicless

public ZstdDecompressCtx setMagicless(boolean magiclessFlag)

Enable or disable magicless frames

Parameters:

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

loadDict

public ZstdDecompressCtx loadDict(ZstdDictDecompress dict)

Load decompression dictionary

Parameters:

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

loadDDictFast0

private static long loadDDictFast0(long nativePtr,
                                   ZstdDictDecompress dict)

loadDict

public ZstdDecompressCtx loadDict(byte[] dict)

Load decompression dictionary.

Parameters:

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

loadDDict0

private static long loadDDict0(long nativePtr,
                               byte[] dict)

reset

public void reset()

Clear all state and parameters from the decompression context. This leaves the object in a state identical to a newly created decompression context.

reset0

private static void reset0(long nativePtr)

ensureOpen

private void ensureOpen()

decompressDirectByteBufferStream

public boolean decompressDirectByteBufferStream(java.nio.ByteBuffer dst,
                                                java.nio.ByteBuffer src)

Decompress as much of the src ByteBuffer into the dst ByteBuffer as possible.

Parameters:

dst - destination of uncompressed data

src - buffer to decompress

Returns:

true if all state has been flushed from internal buffers

decompressDirectByteBufferStream0

private static long decompressDirectByteBufferStream0(long nativePtr,
                                                      java.nio.ByteBuffer dst,
                                                      int dstOffset,
                                                      int dstSize,
                                                      java.nio.ByteBuffer src,
                                                      int srcOffset,
                                                      int srcSize)

4 pieces of information are packed into the return value of this method, which must be treated as an unsigned long. The highest bit is set if all data has been flushed from internal buffers. The next 31 bits are the new position of the destination buffer. The next bit is set if an error occurred. If an error occurred, the lowest 31 bits encode a zstd error code. Otherwise, the lowest 31 bits are the new position of the source buffer.

decompressDirectByteBuffer

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

Decompresses buffer 'srcBuff' into buffer 'dstBuff' using this ZstdDecompressCtx. Destination buffer should be sized to be larger of equal to the originalSize. This is a low-level function that does not take into account or affect the `limit` or `position` of source or destination buffers.

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 size of 'srcBuff'

Returns:

the number of bytes decompressed into destination buffer (originalSize)

decompressDirectByteBuffer0

private static long decompressDirectByteBuffer0(long nativePtr,
                                                java.nio.ByteBuffer dst,
                                                int dstOffset,
                                                int dstSize,
                                                java.nio.ByteBuffer src,
                                                int srcOffset,
                                                int srcSize)

decompressByteArray

public int decompressByteArray(byte[] dstBuff,
                               int dstOffset,
                               int dstSize,
                               byte[] srcBuff,
                               int srcOffset,
                               int srcSize)

Decompresses byte array 'srcBuff' into byte array 'dstBuff' using this ZstdDecompressCtx. Destination buffer should be sized to be larger of equal to the originalSize.

Parameters:

dstBuff - the destination buffer

dstOffset - the start offset of 'dstBuff'

dstSize - the size of 'dstBuff'

srcBuff - the source buffer

srcOffset - the start offset of 'srcBuff'

srcSize - the size of 'srcBuff'

Returns:

the number of bytes decompressed into destination buffer (originalSize)

decompressByteArray0

private static long decompressByteArray0(long nativePtr,
                                         byte[] dst,
                                         int dstOffset,
                                         int dstSize,
                                         byte[] src,
                                         int srcOffset,
                                         int srcSize)

decompress

public int decompress(java.nio.ByteBuffer dstBuf,
                      java.nio.ByteBuffer srcBuf)
               throws ZstdException

Decompresses buffer 'srcBuff' into buffer 'dstBuff' using this ZstdDecompressCtx. Destination buffer should be sized to be larger of equal to the originalSize.

Parameters:

dstBuf - the destination buffer - must be direct. It is assumed that the `position()` of this buffer marks the offset at which the decompressed data are to be written, and that the `limit()` of this buffer is the maximum decompressed data size to allow.

When this method returns successfully, its `position()` will be set to its current `position()` plus the decompressed size of the data.

srcBuf - the source buffer - must be direct. It is assumed that the `position()` of this buffer marks the beginning of the compressed data to be decompressed, and that the `limit()` of this buffer marks its end.

When this method returns successfully, its `position()` will be set to the initial `limit()`.

Returns:

the size of the decompressed data.

Throws:

ZstdException

decompress

public java.nio.ByteBuffer decompress(java.nio.ByteBuffer srcBuf,
                                      int originalSize)
                               throws ZstdException

Throws:

ZstdException

decompress

public int decompress(byte[] dst,
                      byte[] src)

decompress

public byte[] decompress(byte[] src,
                         int originalSize)
                  throws ZstdException

Decompress data

Parameters:

src - the source buffer

originalSize - the maximum size of the uncompressed data. If originaSize is greater than the actuall uncompressed size, additional memory copy going to happen. If originalSize is smaller than the uncompressed size, ZstdExeption will be thrown.

Returns:

byte array with the decompressed data

Throws:

ZstdException