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Class java.util.zip.Inflater

java.lang.Object
    |
    +----java.util.zip.Inflater

public class Inflater
extends Object
This class provides support for general purpose decompression using the popular ZLIB compression library. The ZLIB compression library was initially developed as part of the PNG graphics standard and is not protected by patents. It is fully described in RFCs 1950, 1951, and 1952, which can be found at ftp://ds.internic.net/rfc in the files rfc1950.txt (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).

See Also:
Deflater

Constructor Summary
 Inflater(boolean nowrap)
Creates a new decompressor.
 Inflater()
Creates a new decompressor.
 

Method Summary
void  end()
Discards unprocessed input and frees internal data.
void  finalize()
Frees the decompressor when garbage is collected.
boolean  finished()
Return true if the end of the compressed data stream has been reached.
int  getAdler()
Returns the ADLER-32 value of the uncompressed data.
int  getRemaining()
Returns the total number of bytes remaining in the input buffer.
int  getTotalIn()
Returns the total number of bytes input so far.
int  getTotalOut()
Returns the total number of bytes output so far.
int  inflate(byte[] b, int off, int len)
Uncompresses bytes into specified buffer.
int  inflate(byte[] b)
Uncompresses bytes into specified buffer.
boolean  needsDictionary()
Returns true if a preset dictionary is needed for decompression.
boolean  needsInput()
Returns true if no data remains in the input buffer.
void  reset()
Resets inflater so that a new set of input data can be processed.
void  setDictionary(byte[] b, int off, int len)
Sets the preset dictionary to the given array of bytes.
void  setDictionary(byte[] b)
Sets the preset dictionary to the given array of bytes.
void  setInput(byte[] b, int off, int len)
Sets input data for decompression.
void  setInput(byte[] b)
Sets input data for decompression.
 
Methods inherited from class java.lang.Object
 clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Inflater

public Inflater(boolean nowrap)
Creates a new decompressor. If the parameter 'nowrap' is true then the ZLIB header and checksum fields will not be used in order to support the compression format used by both GZIP and PKZIP.
Parameters:
nowrap - if true then support GZIP compatible compression

Inflater

public Inflater()
Creates a new decompressor.
Method Detail

setInput

public void setInput(byte[] b,
                     int off,
                     int len)
Sets input data for decompression. Should be called whenever needsInput() returns true indicating that more input data is required.
Parameters:
b - the input data bytes
off - the start offset of the input data
len - the length of the input data
See Also:
needsInput

setInput

public void setInput(byte[] b)
Sets input data for decompression. Should be called whenever needsInput() returns true indicating that more input data is required.
Parameters:
b - the input data bytes
See Also:
needsInput

setDictionary

public void setDictionary(byte[] b,
                          int off,
                          int len)
Sets the preset dictionary to the given array of bytes. Should be called when inflate() returns 0 and needsDictionary() returns true indicating that a preset dictionary is required. The method getAdler() can be used to get the Adler-32 value of the dictionary needed.
Parameters:
b - the dictionary data bytes
off - the start offset of the data
len - the length of the data
See Also:
needsDictionary, getAdler

setDictionary

public void setDictionary(byte[] b)
Sets the preset dictionary to the given array of bytes. Should be called when inflate() returns 0 and needsDictionary() returns true indicating that a preset dictionary is required. The method getAdler() can be used to get the Adler-32 value of the dictionary needed.
Parameters:
b - the dictionary data bytes
See Also:
needsDictionary, getAdler

getRemaining

public int getRemaining()
Returns the total number of bytes remaining in the input buffer. This can be used to find out what bytes still remain in the input buffer after decompression has finished.

needsInput

public boolean needsInput()
Returns true if no data remains in the input buffer. This can be used to determine if #setInput should be called in order to provide more input.

needsDictionary

public boolean needsDictionary()
Returns true if a preset dictionary is needed for decompression.
See Also:
InflatesetDictionary

finished

public boolean finished()
Return true if the end of the compressed data stream has been reached.

inflate

public int inflate(byte[] b,
                   int off,
                   int len) throws DataFormatException
Uncompresses bytes into specified buffer. Returns actual number of bytes uncompressed. A return value of 0 indicates that needsInput() or needsDictionary() should be called in order to determine if more input data or a preset dictionary is required. In the later case, getAdler() can be used to get the Adler-32 value of the dictionary required.
Parameters:
b - the buffer for the uncompressed data
off - the start offset of the data
len - the maximum number of uncompressed bytes
Returns:
the actual number of uncompressed bytes
Throws:
DataFormatException - if the compressed data format is invalid
See Also:
needsInput, needsDictionary

inflate

public int inflate(byte[] b) throws DataFormatException
Uncompresses bytes into specified buffer. Returns actual number of bytes uncompressed. A return value of 0 indicates that needsInput() or needsDictionary() should be called in order to determine if more input data or a preset dictionary is required. In the later case, getAdler() can be used to get the Adler-32 value of the dictionary required.
Parameters:
b - the buffer for the uncompressed data
Returns:
the actual number of uncompressed bytes
Throws:
DataFormatException - if the compressed data format is invalid
See Also:
needsInput, needsDictionary

getAdler

public int getAdler()
Returns the ADLER-32 value of the uncompressed data.

getTotalIn

public int getTotalIn()
Returns the total number of bytes input so far.

getTotalOut

public int getTotalOut()
Returns the total number of bytes output so far.

reset

public void reset()
Resets inflater so that a new set of input data can be processed.

end

public void end()
Discards unprocessed input and frees internal data.

finalize

protected void finalize()
Frees the decompressor when garbage is collected.
Overrides:
finalize in class Object

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