Package net.jpountz.lz4

Class LZ4DecompressorWithLength

java.lang.Object

net.jpountz.lz4.LZ4DecompressorWithLength

public class LZ4DecompressorWithLength
extends Object

Convenience class to decompress data compressed by LZ4CompressorWithLength. This decompressor is NOT compatible with any other compressors in lz4-java or any other lz4 tools. The user does not need to specify the length of the compressed data or original data because the length of the original decompressed data is included in the compressed data.

Constructor Summary

Constructors

Constructor	Description
LZ4DecompressorWithLength(LZ4FastDecompressor fastDecompressor)	Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength.
LZ4DecompressorWithLength(LZ4FastDecompressor fastDecompressor, int maxDecompressedLength)	Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength.
LZ4DecompressorWithLength(LZ4SafeDecompressor safeDecompressor)	Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength.
LZ4DecompressorWithLength(LZ4SafeDecompressor safeDecompressor, int maxDecompressedLength)	Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength.

Method Summary

Modifier and Type	Method	Description
byte[]	decompress(byte[] src)	Convenience method, equivalent to calling decompress(src, 0).
int	decompress(byte[] src, byte[] dest)	Convenience method, equivalent to calling decompress(src, 0, dest, 0).
byte[]	decompress(byte[] src, int srcOff)	Convenience method which returns src[srcOff:] decompressed when LZ4FastDecompressor was specified to the constructor, or src[srcOff:src.length] decompressed when LZ4SafeDecompressor was specified to the constructor.
int	decompress(byte[] src, int srcOff, byte[] dest, int destOff)	When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:src.length] into dest[destOff:] and returns the number of decompressed bytes written into dest.
byte[]	decompress(byte[] src, int srcOff, int srcLen)	Convenience method which returns src[srcOff:] decompressed when LZ4FastDecompressor was specified to the constructor, or src[srcOff:srcOff+srcLen] decompressed when LZ4SafeDecompressor was specified to the constructor.
int	decompress(byte[] src, int srcOff, int srcLen, byte[] dest, int destOff)	When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:srcOff+srcLen] into dest[destOff:] and returns the number of decompressed bytes written into dest.
int	decompress(ByteBuffer src, int srcOff, int srcLen, ByteBuffer dest, int destOff)	When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:srcOff+srcLen] into dest[destOff:] and returns the number of decompressed bytes written into dest.
int	decompress(ByteBuffer src, int srcOff, ByteBuffer dest, int destOff)	When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:src.remaining()] into dest[destOff:] and returns the number of decompressed bytes written into dest.
void	decompress(ByteBuffer src, ByteBuffer dest)	Decompresses src into dest.
static int	getDecompressedLength(byte[] src)	Returns the decompressed length of compressed data in src.
static int	getDecompressedLength(byte[] src, int srcOff)	Returns the decompressed length of compressed data in src[srcOff:].
static int	getDecompressedLength(ByteBuffer src)	Returns the decompressed length of compressed data in src.
static int	getDecompressedLength(ByteBuffer src, int srcOff)	Returns the decompressed length of compressed data in src[srcOff:].

Methods inherited from class java.lang.Object

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

Constructor Details

LZ4DecompressorWithLength

public LZ4DecompressorWithLength(LZ4FastDecompressor fastDecompressor)

Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength. Methods that allocate their output buffer reject decompressed lengths greater than 64 MiB. Note that it is deprecated to use a JNI-binding instance of LZ4FastDecompressor. Please see LZ4Factory.nativeInstance() for details.

Parameters:

fastDecompressor - fast decompressor to use

LZ4DecompressorWithLength

public LZ4DecompressorWithLength(LZ4FastDecompressor fastDecompressor,
 int maxDecompressedLength)

Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength. Note that it is deprecated to use a JNI-binding instance of LZ4FastDecompressor. Please see LZ4Factory.nativeInstance() for details.

Parameters:

fastDecompressor - fast decompressor to use

maxDecompressedLength - maximum decompressed length for methods that allocate their output buffer

Throws:

IllegalArgumentException - if maxDecompressedLength is negative

Since:

1.11.2

LZ4DecompressorWithLength

public LZ4DecompressorWithLength(LZ4SafeDecompressor safeDecompressor)

Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength. Methods that allocate their output buffer reject decompressed lengths greater than 64 MiB.

Parameters:

safeDecompressor - safe decompressor to use

LZ4DecompressorWithLength

public LZ4DecompressorWithLength(LZ4SafeDecompressor safeDecompressor,
 int maxDecompressedLength)

Creates a new decompressor to decompress data compressed by LZ4CompressorWithLength.

Parameters:

safeDecompressor - safe decompressor to use

maxDecompressedLength - maximum decompressed length for methods that allocate their output buffer

Throws:

IllegalArgumentException - if maxDecompressedLength is negative

Since:

1.11.2

Method Details

getDecompressedLength

public static int getDecompressedLength(byte[] src)

Returns the decompressed length of compressed data in src.

Parameters:

src - the compressed data

Returns:

the decompressed length, without validating it against the compressed data

getDecompressedLength

public static int getDecompressedLength(byte[] src,
 int srcOff)

Returns the decompressed length of compressed data in src[srcOff:].

Parameters:

src - the compressed data

srcOff - the start offset in src

Returns:

the decompressed length, without validating it against the compressed data

getDecompressedLength

public static int getDecompressedLength(ByteBuffer src)

Returns the decompressed length of compressed data in src.

Parameters:

src - the compressed data

Returns:

the decompressed length, without validating it against the compressed data

getDecompressedLength

public static int getDecompressedLength(ByteBuffer src,
 int srcOff)

Returns the decompressed length of compressed data in src[srcOff:].

Parameters:

src - the compressed data

srcOff - the start offset in src

Returns:

the decompressed length, without validating it against the compressed data

decompress

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

Convenience method, equivalent to calling decompress(src, 0, dest, 0).

Parameters:

src - the compressed data

dest - the destination buffer to store the decompressed data

Returns:

the number of bytes read to restore the original input

decompress

public int decompress(byte[] src,
 int srcOff,
 byte[] dest,
 int destOff)

When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:src.length] into dest[destOff:] and returns the number of decompressed bytes written into dest.

Parameters:

src - the compressed data

srcOff - the start offset in src

dest - the destination buffer to store the decompressed data

destOff - the start offset in dest

Returns:

the number of bytes read to restore the original input (when LZ4FastDecompressor is used), or the number of decompressed bytes (when LZ4SafeDecompressor is used)

decompress

public int decompress(byte[] src,
 int srcOff,
 int srcLen,
 byte[] dest,
 int destOff)

When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:srcOff+srcLen] into dest[destOff:] and returns the number of decompressed bytes written into dest.

Parameters:

src - the compressed data

srcOff - the start offset in src

srcLen - the exact size of the compressed data (ignored when LZ4FastDecompressor is used)

dest - the destination buffer to store the decompressed data

destOff - the start offset in dest

Returns:

the number of bytes read to restore the original input (when LZ4FastDecompressor is used), or the number of decompressed bytes (when LZ4SafeDecompressor is used)

decompress

public byte[] decompress(byte[] src)

Convenience method, equivalent to calling decompress(src, 0).

Parameters:

src - the compressed data

Returns:

the decompressed data

Throws:

LZ4Exception - if the declared decompressed length is invalid or exceeds the configured maximum

decompress

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

Convenience method which returns src[srcOff:] decompressed when LZ4FastDecompressor was specified to the constructor, or src[srcOff:src.length] decompressed when LZ4SafeDecompressor was specified to the constructor.

Warning: this method has an important overhead due to the fact that it needs to allocate a buffer to decompress into.

Parameters:

src - the compressed data

srcOff - the start offset in src

Returns:

the decompressed data

Throws:

LZ4Exception - if the declared decompressed length is invalid or exceeds the configured maximum

decompress

public byte[] decompress(byte[] src,
 int srcOff,
 int srcLen)

Convenience method which returns src[srcOff:] decompressed when LZ4FastDecompressor was specified to the constructor, or src[srcOff:srcOff+srcLen] decompressed when LZ4SafeDecompressor was specified to the constructor.

Warning: this method has an important overhead due to the fact that it needs to allocate a buffer to decompress into.

Parameters:

src - the compressed data

srcOff - the start offset in src

srcLen - the exact size of the compressed data (ignored when LZ4FastDecompressor is used)

Returns:

the decompressed data

Throws:

LZ4Exception - if the declared decompressed length is invalid or exceeds the configured maximum

decompress

public void decompress(ByteBuffer src,
 ByteBuffer dest)

Decompresses src into dest. When LZ4SafeDecompressor was specified to the constructor, src's Buffer.remaining() must be exactly the size of the compressed data. This method moves the positions of the buffers.

Parameters:

src - the compressed data

dest - the destination buffer to store the decompressed data

decompress

public int decompress(ByteBuffer src,
 int srcOff,
 ByteBuffer dest,
 int destOff)

When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:src.remaining()] into dest[destOff:] and returns the number of decompressed bytes written into dest. The positions and limits of the ByteBuffers remain unchanged.

Parameters:

src - the compressed data

srcOff - the start offset in src

dest - the destination buffer to store the decompressed data

destOff - the start offset in dest

Returns:

the number of bytes read to restore the original input (when LZ4FastDecompressor is used), or the number of decompressed bytes (when LZ4SafeDecompressor is used)

decompress

public int decompress(ByteBuffer src,
 int srcOff,
 int srcLen,
 ByteBuffer dest,
 int destOff)

When LZ4FastDecompressor was specified to the constructor, decompresses src[srcOff:] into dest[destOff:] and returns the number of bytes read from src, and when LZ4SafeDecompressor was specified to the constructor, decompresses src[srcOff:srcOff+srcLen] into dest[destOff:] and returns the number of decompressed bytes written into dest. The positions and limits of the ByteBuffers remain unchanged.

Parameters:

src - the compressed data

srcOff - the start offset in src

srcLen - the exact size of the compressed data (ignored when LZ4FastDecompressor is used)

dest - the destination buffer to store the decompressed data

destOff - the start offset in dest

Returns:

the number of bytes read to restore the original input (when LZ4FastDecompressor is used), or the number of decompressed bytes (when LZ4SafeDecompressor is used)