Package nom.tam.fits.compress

Class ZCompressionProvider

java.lang.Object

nom.tam.fits.compress.ZCompressionProvider

All Implemented Interfaces:

ICompressProvider

public class ZCompressionProvider
extends Object
implements ICompressProvider

(for internal use) UNIX compressed (.Z) input stream decompression. You can use this class to decompress files that have been compressed with the UNIX compress tool (or via gzip) and have the characteristic .Z file name extension. Or, use CompressionManager to automatically detect the type of compression used. This class uses the Apache commons-compress package to perform the decompression.

See Also:

• CompressionManager

Constructor Summary

Constructors

Constructor	Description
ZCompressionProvider()

Method Summary

Modifier and Type	Method	Description
InputStream	decompress(InputStream in)	Decompresses data from an input stream.
int	priority()	Returns the priority of this method.
boolean	provides(int mag1, int mag2)	Checks if this compression method can support the magic integer number that is used to identify the type of compression at the beginning of compressed files, and is stored as the first 2 bytes of compressed data.

Methods inherited from class java.lang.Object

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

Constructor Details

ZCompressionProvider

public ZCompressionProvider()

Method Details

decompress

public InputStream decompress(InputStream in)
                       throws IOException

Description copied from interface: ICompressProvider

Decompresses data from an input stream.

Specified by:

decompress in interface ICompressProvider

Parameters:

in - the input stream containing compressed data

Returns:

a new input stream containing the decompressed data

Throws:

IOException - if there was an IO error while accessing the input stream

priority

public int priority()

Description copied from interface: ICompressProvider

Returns the priority of this method. CompressionManager will use this to select the 'best' compression class when multiple compression classes can provide decompression support for a given input stream. Claases that have a higher priority will be preferred.

Specified by:

priority in interface ICompressProvider

Returns:

the priority of this decompression method vs similar other compression methods that may be avaialble.

See Also:

• CompressionManager

provides

public boolean provides(int mag1,
 int mag2)

Description copied from interface: ICompressProvider

Checks if this compression method can support the magic integer number that is used to identify the type of compression at the beginning of compressed files, and is stored as the first 2 bytes of compressed data.

Specified by:

provides in interface ICompressProvider

Parameters:

mag1 - the first byte of the compressed file

mag2 - the second byte of the compressed file

Returns:

true if this class can be used to decompress the given file, or else false.