org.at4j.comp.gzip.prog

Class GZip

java.lang.Object

org.at4j.support.prog.AbstractProgram

org.at4j.comp.prog.AbstractStreamCompressionProgram<T>

org.at4j.comp.gzip.prog.GZip

public final class GZip
extends AbstractStreamCompressionProgram<T>

This runnable class emulates the gzip command. It understands a subset of gzip's command line arguments.

The program compresses one or several files. A file is compressed to a new file with ".gz" added to the name of the original file. The original file is deleted after it has been successfully compressed.

 Usage:
   java -cp [classpath] org.at4j.comp.gzip.prog.GZip [options] file[s]
 Where:
   classpath - Should include the at4j and entityfs-core Jars.
   options   - Command options. See below.
   file[s]   - The files to compress.
 Options:
   -c        - Write the compressed data to standard output and do not delete
               the original files.
   --decompress
   --uncompress
   -d        - Decompress files (instead of compressing them).
   --suffix suf
   -S suf    - Use the suffix "suf" instead of ".gz" for the compressed files.
   --threads no - Set the maximum number of threads to use for compressing.
               Different files may be compressed in different threads. The
               default number of threads is 1.
   --timing  - After building the archive, print out how long it took.
 

Since:

1.0

Author:

Karl Gustafsson

See Also:

GUnzip

Constructor Summary

Constructors

Constructor and Description
GZip()

Method Summary

Methods

Modifier and Type	Method and Description
protected InputStream	createInputStream(int sourceNo, T settings) Create an input stream on the source entity for the given command line arguments.
protected OutputStream	createOutputStream(int targetNo, T settings) Create an output stream on the target entity for the given command line arguments.
static void	main(String[] args)
protected org.at4j.comp.gzip.prog.GZipCommandLineArguments	parseCommandLine(String[] args) Subclasses implement this to parse their command line.
protected void	postProcess(int sourceNo, T settings) Subclasses may override this for postprocessing the source and/or target entity.

Methods inherited from class org.at4j.comp.prog.AbstractStreamCompressionProgram

run

Methods inherited from class org.at4j.support.prog.AbstractProgram

getArg, getParentLocation, isFlagArgument

Methods inherited from class java.lang.Object

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

Constructor Detail

GZip

public GZip()

Method Detail

parseCommandLine

protected org.at4j.comp.gzip.prog.GZipCommandLineArguments parseCommandLine(String[] args)
                                                                     throws CommandErrorException

Description copied from class: AbstractStreamCompressionProgram

Subclasses implement this to parse their command line.

Specified by:

parseCommandLine in class AbstractStreamCompressionProgram<org.at4j.comp.gzip.prog.GZipCommandLineArguments>

Parameters:

args - The command line arguments, unparsed.

Returns:

The command line arguments, parsed.

Throws:

CommandErrorException - If the commands were invalid.

main

public static void main(String[] args)

createInputStream

protected InputStream createInputStream(int sourceNo,
                            T settings)
                                 throws IOException

Description copied from class: AbstractStreamCompressionProgram

Create an input stream on the source entity for the given command line arguments.

Specified by:

createInputStream in class AbstractStreamCompressionProgram<T extends org.at4j.comp.gzip.prog.AbstractGZipProgramArguments>

Parameters:

sourceNo - The index number for the source entity. The first source has index == 0.

settings - The command line arguments.

Returns:

An input stream on the source.

Throws:

IOException - On I/O errors.

createOutputStream

protected OutputStream createOutputStream(int targetNo,
                              T settings)
                                   throws IOException,
                                          IgnoreFileException

Description copied from class: AbstractStreamCompressionProgram

Create an output stream on the target entity for the given command line arguments.

Specified by:

createOutputStream in class AbstractStreamCompressionProgram<T extends org.at4j.comp.gzip.prog.AbstractGZipProgramArguments>

Parameters:

targetNo - The index number for the target entity. The first target has index == 0.

settings - The command line arguments.

Returns:

An output stream on the target.

Throws:

IOException - On I/O errors.

IgnoreFileException - If the file should be ignored for some reason.

postProcess

protected void postProcess(int sourceNo,
               T settings)
                    throws IOException

Description copied from class: AbstractStreamCompressionProgram

Subclasses may override this for postprocessing the source and/or target entity. This implementation does not do anything.

Overrides:

postProcess in class AbstractStreamCompressionProgram<T extends org.at4j.comp.gzip.prog.AbstractGZipProgramArguments>

Parameters:

sourceNo - The index number for the source and target entities.

settings - The command line arguments.

Throws:

IOException - On I/O errors.