Package net.sf.jazzlib

Class GZIPInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

net.sf.jazzlib.InflaterInputStream

net.sf.jazzlib.GZIPInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class GZIPInputStream
extends InflaterInputStream

This filter stream is used to decompress a "GZIP" format stream. The "GZIP" format is described in RFC 1952.

Since:

JDK 1.1

Field Summary

Fields

Modifier and Type	Field	Description
protected CRC32	crc	The CRC-32 checksum value for uncompressed data.
protected boolean	eos	Indicates whether or not the end of the stream has been reached.
(package private) static final int	FCOMMENT	The mask for bit 4 of the flag byte.
(package private) static final int	FEXTRA	The mask for bit 2 of the flag byte.
(package private) static final int	FHCRC	The mask for bit 1 of the flag byte.
(package private) static final int	FNAME	The mask for bit 3 of the flag byte.
(package private) static final int	FTEXT	The mask for bit 0 of the flag byte.
static final int	GZIP_MAGIC	The magic number found at the start of a GZIP stream.
private boolean	readGZIPHeader	Indicates whether or not the GZIP header has been read in.

Fields inherited from class net.sf.jazzlib.InflaterInputStream

buf, inf, len

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor	Description
GZIPInputStream(InputStream in)	Creates a GZIPInputStream with the default buffer size.
GZIPInputStream(InputStream in, int size)	Creates a GZIPInputStream with the specified buffer size.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes the input stream.
int	read(byte[] buf, int offset, int len)	Reads in GZIP-compressed data and stores it in uncompressed form into an array of bytes.
private void	readFooter()
private void	readHeader()	Reads in the GZIP header.

Methods inherited from class net.sf.jazzlib.InflaterInputStream

available, fill, read, skip

Methods inherited from class java.io.FilterInputStream

mark, markSupported, read, reset

Methods inherited from class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, skipNBytes, transferTo

Methods inherited from class java.lang.Object

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

Field Details

GZIP_MAGIC

public static final int GZIP_MAGIC

The magic number found at the start of a GZIP stream.

See Also:

• Constant Field Values

FTEXT

static final int FTEXT

The mask for bit 0 of the flag byte.

See Also:

• Constant Field Values

FHCRC

static final int FHCRC

The mask for bit 1 of the flag byte.

See Also:

• Constant Field Values

FEXTRA

static final int FEXTRA

The mask for bit 2 of the flag byte.

See Also:

• Constant Field Values

FNAME

static final int FNAME

The mask for bit 3 of the flag byte.

See Also:

• Constant Field Values

FCOMMENT

static final int FCOMMENT

The mask for bit 4 of the flag byte.

See Also:

• Constant Field Values

crc

protected CRC32 crc

The CRC-32 checksum value for uncompressed data.

eos

protected boolean eos

Indicates whether or not the end of the stream has been reached.

readGZIPHeader

private boolean readGZIPHeader

Indicates whether or not the GZIP header has been read in.

Constructor Details

GZIPInputStream

public GZIPInputStream(InputStream in)
                throws IOException

Creates a GZIPInputStream with the default buffer size.

Parameters:

in - The stream to read compressed data from (in GZIP format).

Throws:

IOException - if an error occurs during an I/O operation.

GZIPInputStream

public GZIPInputStream(InputStream in,
 int size)
                throws IOException

Creates a GZIPInputStream with the specified buffer size.

Parameters:

in - The stream to read compressed data from (in GZIP format).

size - The size of the buffer to use.

Throws:

IOException - if an error occurs during an I/O operation.

IllegalArgumentException - if size is less than or equal to 0.

Method Details

close

public void close()
           throws IOException

Closes the input stream.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InflaterInputStream

Throws:

IOException - if an error occurs during an I/O operation.

read

public int read(byte[] buf,
 int offset,
 int len)
         throws IOException

Reads in GZIP-compressed data and stores it in uncompressed form into an array of bytes. The method will block until either enough input data becomes available or the compressed stream reaches its end.

Overrides:

read in class InflaterInputStream

Parameters:

buf - the buffer into which the uncompressed data will be stored.

offset - the offset indicating where in buf the uncompressed data should be placed.

len - the number of uncompressed bytes to be read.

Throws:

IOException

readHeader

private void readHeader()
                 throws IOException

Reads in the GZIP header.

Throws:

IOException

readFooter

private void readFooter()
                 throws IOException

Throws:

IOException