C# Class Moxie.PngEncoder.Deflater

This is the Deflater class. The deflater class compresses input with the deflate algorithm described in RFC 1951. It has several compression levels and three different strategies described below. This class is not thread safe. This is inherent in the API, due to the split of deflate and setInput. author of the original java version : Jochen Hoenicke

Show file Open project: openHPI/moodle-mod_teletask Class Usage Examples

Public Methods

Method	Description
Deflate ( byte output ) : int	Deflates the current input block with to the given array.
Deflate ( byte output, int offset, int length ) : int	Deflates the current input block to the given array.
Deflater ( ) : System	Creates a new deflater with default compression level.
Deflater ( int level ) : System	Creates a new deflater with given compression level.
Deflater ( int level, bool noZlibHeaderOrFooter ) : System	Creates a new deflater with given compression level.
Finish ( ) : void	Finishes the deflater with the current input block. It is an error to give more input after this method was called. This method must be called to force all bytes to be flushed.
Flush ( ) : void	Flushes the current input block. Further calls to deflate() will produce enough output to inflate everything in the current input block. This is not part of Sun's JDK so I have made it package private. It is used by DeflaterOutputStream to implement flush().
GetLevel ( ) : int	Get current compression level
Reset ( ) : void	Resets the deflater. The deflater acts afterwards as if it was just created with the same compression level and strategy as it had before.
SetDictionary ( byte dictionary ) : void	Sets the dictionary which should be used in the deflate process. This call is equivalent to `setDictionary(dict, 0, dict.Length)`.
SetDictionary ( byte dictionary, int index, int count ) : void	Sets the dictionary which should be used in the deflate process. The dictionary is a byte array containing strings that are likely to occur in the data which should be compressed. The dictionary is not stored in the compressed output, only a checksum. To decompress the output you need to supply the same dictionary again.
SetInput ( byte input ) : void	Sets the data which should be compressed next. This should be only called when needsInput indicates that more input is needed. If you call setInput when needsInput() returns false, the previous input that is still pending will be thrown away. The given byte array should not be changed, before needsInput() returns true again. This call is equivalent to `setInput(input, 0, input.length)`.
SetInput ( byte input, int offset, int count ) : void	Sets the data which should be compressed next. This should be only called when needsInput indicates that more input is needed. The given byte array should not be changed, before needsInput() returns true again.
SetLevel ( int level ) : void	Sets the compression level. There is no guarantee of the exact position of the change, but if you call this when needsInput is true the change of compression level will occur somewhere near before the end of the so far given input.
SetStrategy ( DeflateStrategy strategy ) : void	Sets the compression strategy. Strategy is one of DEFAULT_STRATEGY, HUFFMAN_ONLY and FILTERED. For the exact position where the strategy is changed, the same as for SetLevel() applies.

Method Details

Deflate() public method

Deflates the current input block with to the given array.

public Deflate ( byte output ) : int
output	byte	/// The buffer where compressed data is stored ///
return	int

Deflate() public method

Deflates the current input block to the given array.

/// If Finish() was previously called. /// /// If offset or length don't match the array length. ///

public Deflate ( byte output, int offset, int length ) : int
output	byte	/// Buffer to store the compressed data. ///
offset	int	/// Offset into the output array. ///
length	int	/// The maximum number of bytes that may be stored. ///
return	int

Deflater() public method

Creates a new deflater with default compression level.

public Deflater ( ) : System
return	System

Deflater() public method

Creates a new deflater with given compression level.

if lvl is out of range.

public Deflater ( int level ) : System
level	int	/// the compression level, a value between NO_COMPRESSION /// and BEST_COMPRESSION, or DEFAULT_COMPRESSION. ///
return	System

Deflater() public method

Creates a new deflater with given compression level.

if lvl is out of range.

public Deflater ( int level, bool noZlibHeaderOrFooter ) : System
level	int	/// the compression level, a value between NO_COMPRESSION /// and BEST_COMPRESSION. ///
noZlibHeaderOrFooter	bool	/// true, if we should suppress the Zlib/RFC1950 header at the /// beginning and the adler checksum at the end of the output. This is /// useful for the GZIP/PKZIP formats. ///
return	System

Finish() public method

Finishes the deflater with the current input block. It is an error to give more input after this method was called. This method must be called to force all bytes to be flushed.

public Finish ( ) : void
return	void

Flush() public method

Flushes the current input block. Further calls to deflate() will produce enough output to inflate everything in the current input block. This is not part of Sun's JDK so I have made it package private. It is used by DeflaterOutputStream to implement flush().

public Flush ( ) : void
return	void

GetLevel() public method

Get current compression level

public GetLevel ( ) : int
return	int

Reset() public method

Resets the deflater. The deflater acts afterwards as if it was just created with the same compression level and strategy as it had before.

public Reset ( ) : void
return	void

SetDictionary() public method

Sets the dictionary which should be used in the deflate process. This call is equivalent to setDictionary(dict, 0, dict.Length).

/// if SetInput () or Deflate () were already called or another dictionary was already set. ///

public SetDictionary ( byte dictionary ) : void
dictionary	byte	/// the dictionary. ///
return	void

SetDictionary() public method

Sets the dictionary which should be used in the deflate process. The dictionary is a byte array containing strings that are likely to occur in the data which should be compressed. The dictionary is not stored in the compressed output, only a checksum. To decompress the output you need to supply the same dictionary again.

/// If SetInput () or Deflate() were already called or another dictionary was already set. ///

public SetDictionary ( byte dictionary, int index, int count ) : void
dictionary	byte	/// The dictionary data ///
index	int	/// The index where dictionary information commences. ///
count	int	/// The number of bytes in the dictionary. ///
return	void

SetInput() public method

Sets the data which should be compressed next. This should be only called when needsInput indicates that more input is needed. If you call setInput when needsInput() returns false, the previous input that is still pending will be thrown away. The given byte array should not be changed, before needsInput() returns true again. This call is equivalent to setInput(input, 0, input.length).

/// if the buffer was finished() or ended(). ///

public SetInput ( byte input ) : void
input	byte	/// the buffer containing the input data. ///
return	void

SetInput() public method

Sets the data which should be compressed next. This should be only called when needsInput indicates that more input is needed. The given byte array should not be changed, before needsInput() returns true again.

/// if the buffer was Finish()ed or if previous input is still pending. ///

public SetInput ( byte input, int offset, int count ) : void
input	byte	/// the buffer containing the input data. ///
offset	int	/// the start of the data. ///
count	int	/// the number of data bytes of input. ///
return	void

SetLevel() public method

Sets the compression level. There is no guarantee of the exact position of the change, but if you call this when needsInput is true the change of compression level will occur somewhere near before the end of the so far given input.

public SetLevel ( int level ) : void
level	int	/// the new compression level. ///
return	void

SetStrategy() public method

Sets the compression strategy. Strategy is one of DEFAULT_STRATEGY, HUFFMAN_ONLY and FILTERED. For the exact position where the strategy is changed, the same as for SetLevel() applies.

public SetStrategy ( DeflateStrategy strategy ) : void
strategy	DeflateStrategy	/// The new compression strategy. ///
return	void