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java.lang.Objectorg.h2.compress.CompressLZF
public final class CompressLZF
This class implements the LZF lossless data compression algorithm. LZF is a Lempel-Ziv variant with byte-aligned output, and optimized for speed.
Safety/Use Notes:
The LZF compressed format knows literal runs and back-references:
The first byte of the compressed stream is the control byte. For literal runs, the highest three bits of the control byte are not set, the the lower bits are the literal run length, and the next bytes are data to copy directly into the output. For back-references, the highest three bits of the control byte are the back-reference length. If all three bits are set, then the back-reference length is stored in the next byte. The lower bits of the control byte combined with the next byte form the offset for the back-reference.
Field Summary |
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Fields inherited from interface org.h2.compress.Compressor |
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DEFLATE, LZF, NO |
Constructor Summary | |
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CompressLZF()
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Method Summary | |
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int |
compress(byte[] in,
int inLen,
byte[] out,
int outPos)
Compress a number of bytes. |
void |
expand(byte[] in,
int inPos,
int inLen,
byte[] out,
int outPos,
int outLen)
Expand a number of compressed bytes. |
int |
getAlgorithm()
Get the compression algorithm type. |
void |
setOptions(java.lang.String options)
Set the compression options. |
Methods inherited from class java.lang.Object |
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clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Constructor Detail |
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public CompressLZF()
Method Detail |
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public void setOptions(java.lang.String options)
Compressor
setOptions
in interface Compressor
options
- the optionspublic int compress(byte[] in, int inLen, byte[] out, int outPos)
Compressor
compress
in interface Compressor
in
- the input datainLen
- the number of bytes to compressout
- the output areaoutPos
- the offset at the output array
public void expand(byte[] in, int inPos, int inLen, byte[] out, int outPos, int outLen)
Compressor
expand
in interface Compressor
in
- the compressed datainPos
- the offset at the input arrayinLen
- the number of bytes to readout
- the output areaoutPos
- the offset at the output arrayoutLen
- the size of the uncompressed datapublic int getAlgorithm()
Compressor
getAlgorithm
in interface Compressor
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