TarTool example source code file (tar.java)

This example TarTool source code file (tar.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - TarTool tags/keywords

activation, could, could, file, file, inputstream, io, ioexception, ioexception, net, network, numberformatexception, string, string, tararchive, the, throwable, zip

The TarTool tar.java source code

/*
** Authored by Timothy Gerard Endres
** <mailto:time@gjt.org>  
** 
** This work has been placed into the public domain.
** You may use this work in any way and for any purpose you wish.
**
** THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY OF ANY KIND,
** NOT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY. THE AUTHOR
** OF THIS SOFTWARE, ASSUMES _NO_ RESPONSIBILITY FOR ANY
** CONSEQUENCE RESULTING FROM THE USE, MODIFICATION, OR
** REDISTRIBUTION OF THIS SOFTWARE. 
** 
*/

package com.ice.tar;

import java.io.*;
import java.net.*;
import java.util.zip.*;
import javax.activation.*;

/**
 * The tar class implements a weak reproduction of the
 * traditional UNIX tar command. It currently supports
 * creating, listing, and extracting from archives. It
 * also supports GZIP-ed archives with the '-z' flag.
 * See the usage (-? or --usage) for option details.
 *
 * @version $Revision: 1.8 $
 * @author Timothy Gerard Endres,
 *  <a href="mailto:time@gjt.org">time@gjt.org.
 * @see TarArchive
 */

public class
tar extends Object
	implements TarProgressDisplay
	{
	/**
	 * Flag that determines if debugging information is displayed.
	 */
	private boolean		debug;
	/**
	 * Flag that determines if verbose feedback is provided.
	 */
	private boolean		verbose;
	/**
	 * Flag that determines if IO is GZIP-ed ('-z' option).
	 */
	private boolean		compressed;
	/**
	 * True if we are listing the archive. False if writing or extracting.
	 */
	private boolean		listingArchive;
	/**
	 * True if we are writing the archive. False if we are extracting it.
	 */
	private boolean		writingArchive;
	/**
	 * True if we are not to overwrite existing files.
	 */
	private boolean		keepOldFiles;
	/**
	 * True if we are to convert ASCII text files from local line endings
	 * to the UNIX standard '\n'.
	 */
	private boolean		asciiTranslate;
	/**
	 * True if a MIME file has been loaded with the '--mime' option.
	 */
	private boolean		mimeFileLoaded;

	/**
	 * The archive name provided on the command line, null if stdio.
	 */
	private String		archiveName;

	/**
	 * The blocksize to use for the tar archive IO. Set by the '-b' option.
	 */
	private int			blockSize;

	/**
	 * The userId to use for files written to archives. Set by '-U' option.
	 */
	private int			userId;
	/**
	 * The userName to use for files written to archives. Set by '-u' option.
	 */
	private String		userName;
	/**
	 * The groupId to use for files written to archives. Set by '-G' option.
	 */
	private int			groupId;
	/**
	 * The groupName to use for files written to archives. Set by '-g' option.
	 */
	private String		groupName;


	/**
	 * The main entry point of the tar class.
	 */
	public static void
	main( String argv[] )
		{
		tar app = new tar();

		app.instanceMain( argv );
		}

	/**
	 * Establishes the default userName with the 'user.name' property.
	 */
	public
	tar()
		{
		this.debug = false;
		this.verbose = false;
		this.compressed = false;
		this.archiveName = null;
		this.listingArchive = false;
		this.writingArchive = true;
		this.keepOldFiles = false;
		this.asciiTranslate = false;

		this.blockSize = TarBuffer.DEFAULT_BLKSIZE;

		String sysUserName =
			System.getProperty( "user.name" );

		this.userId = 0;
		this.userName =
			( (sysUserName == null) ? "" : sysUserName );

		this.groupId = 0;
		this.groupName = "";
		}

	/**
	 * This is the "real" main. The class main() instantiates a tar object
	 * for the application and then calls this method. Process the arguments
	 * and perform the requested operation.
	 */
	public void
	instanceMain( String argv[] )
		{
		TarArchive archive = null;

		int argIdx = this.processArguments( argv );

		if ( writingArchive )				// WRITING
			{
			OutputStream outStream = System.out;

			if ( this.archiveName != null
					&& ! this.archiveName.equals( "-" ) )
				{
				try {
					outStream = new FileOutputStream( this.archiveName );
					}
				catch ( IOException ex )
					{
					outStream = null;
					ex.printStackTrace( System.err );
					}
				}

			if ( outStream != null )
				{
				if ( this.compressed )
					{
					try {
						outStream = new GZIPOutputStream( outStream );
						}
					catch ( IOException ex )
						{
						outStream = null;
						ex.printStackTrace( System.err );
						}
					}
				
				archive = new TarArchive( outStream, this.blockSize );
				}
			}
		else								// EXTRACING OR LISTING
			{
			InputStream inStream = System.in;

			if ( this.archiveName != null
					&& ! this.archiveName.equals( "-" ) )
				{
				try {
					inStream = new FileInputStream( this.archiveName );
					}
				catch ( IOException ex )
					{
					inStream = null;
					ex.printStackTrace( System.err );
					}
				}

			if ( inStream != null )
				{
				if ( this.compressed )
					{
					try {
						inStream = new GZIPInputStream( inStream );
						}
					catch ( IOException ex )
						{
						inStream = null;
						ex.printStackTrace( System.err );
						}
					}

				archive = new TarArchive( inStream, this.blockSize );
				}
			}

		if ( archive != null )						// SET ARCHIVE OPTIONS
			{
			archive.setDebug( this.debug );
			archive.setVerbose( this.verbose );
			archive.setTarProgressDisplay( this );
			archive.setKeepOldFiles( this.keepOldFiles );
			archive.setAsciiTranslation( this.asciiTranslate );

			archive.setUserInfo(
					this.userId, this.userName,
					this.groupId, this.groupName );
			}

		if ( archive == null )
			{
			System.err.println( "no processing due to errors" );
			}
		else if ( this.writingArchive )				// WRITING
			{
			for ( ; argIdx < argv.length ; ++argIdx )
				{
				try {
					File f = new File( argv[ argIdx ] );
				
					TarEntry entry = new TarEntry( f );

					archive.writeEntry( entry, true );
					}
				catch ( IOException ex )
					{
					ex.printStackTrace( System.err );
					}
				}
			}
		else if ( this.listingArchive )				// LISTING
			{
			try {
				archive.listContents();
				}
			catch ( InvalidHeaderException ex )
				{
				ex.printStackTrace( System.err );
				}
			catch ( IOException ex )
				{
				ex.printStackTrace( System.err );
				}
			}
		else										// EXTRACTING
			{
			String userDir =
				System.getProperty( "user.dir", null );

			File destDir = new File( userDir );
			if ( ! destDir.exists() )
				{
				if ( ! destDir.mkdirs() )
					{
					destDir = null;
					Throwable ex = new Throwable
						( "ERROR, mkdirs() on '" + destDir.getPath()
							+ "' returned false." );
					ex.printStackTrace( System.err );
					}
				}

			if ( destDir != null )
				{
				try {
					archive.extractContents( destDir );
					}
				catch ( InvalidHeaderException ex )
					{
					ex.printStackTrace( System.err );
					}
				catch ( IOException ex )
					{
					ex.printStackTrace( System.err );
					}
				}
			}

		if ( archive != null )						// CLOSE ARCHIVE
			{
			try {
				archive.closeArchive();
				}
			catch ( IOException ex )
				{
				ex.printStackTrace( System.err );
				}
			}
		}

	/**
	 * Process arguments, handling options, and return the index of the
	 * first non-option argument.
	 *
	 * @return The index of the first non-option argument.
	 */

	private int
	processArguments( String args[] )
		{
		int idx = 0;
		boolean gotOP = false;

		for ( ; idx < args.length ; ++idx )
			{
			String arg = args[ idx ];

			if ( ! arg.startsWith( "-" ) )
				break;

			if ( arg.startsWith( "--" ) )
				{
				if ( arg.equals( "--usage" ) )
					{
					this.usage();
					System.exit(1);
					}
				else if ( arg.equals( "--version" ) )
					{
					this.version();
					System.exit(1);
					}
				else if ( arg.equals( "--trans" ) )
					{
					this.asciiTranslate = true;

					String jafClassName =
						"javax.activation.FileTypeMap";

					try {
						Class jafClass =
							Class.forName( jafClassName );

						if ( ! this.mimeFileLoaded )
							{
							URL mimeURL =
								tar.class.getResource
									( "/com/ice/tar/asciimime.txt" );

							URLConnection mimeConn =
								mimeURL.openConnection();

							InputStream in = mimeConn.getInputStream();

							FileTypeMap.setDefaultFileTypeMap
								( new MimetypesFileTypeMap( in ) );
							}
						}
					catch ( ClassNotFoundException ex )
						{
						System.err.println
						( "Could not load the class named '"
							+ jafClassName + "'.\n"
							+ "The Java Activation package must "
							+ "be installed to use ascii translation." );
						System.exit(1);
						}
					catch ( IOException ex )
						{
						ex.printStackTrace( System.err );
						System.exit(1);
						}
					}
				else if ( arg.equals( "--mime" ) )
					{
					this.mimeFileLoaded = true;

					String jafClassName =
						"javax.activation.FileTypeMap";

					File mimeFile = new File( args[ ++idx ] );

					try {
						Class jafClass =
							Class.forName( jafClassName );

						FileTypeMap.setDefaultFileTypeMap(
							new MimetypesFileTypeMap(
								new FileInputStream( mimeFile ) ) );
						}
					catch ( ClassNotFoundException ex )
						{
						System.err.println
						( "Could not load the class named '"
							+ jafClassName + "'.\n"
							+ "The Java Activation package must "
							+ "be installed to use ascii translation." );
						System.exit(1);
						}
					catch ( FileNotFoundException ex )
						{
						System.err.println
						( "Could not open the mimetypes file '"
							+ mimeFile.getPath() + "', " + ex.getMessage() );
						}
					}
				else
					{
					System.err.println
						( "unknown option: " + arg );
					this.usage();
					System.exit(1);
					}
				}
			else for ( int cIdx = 1 ; cIdx < arg.length() ; ++cIdx )
				{
				char ch = arg.charAt( cIdx );

				if ( ch == '?' )
					{
					this.usage();
					System.exit(1);
					}
				else if ( ch == 'f' )
					{
					this.archiveName = args[ ++idx ];
					}
				else if ( ch == 'z' )
					{
					this.compressed = true;
					}
				else if ( ch == 'c' )
					{
					gotOP = true;
					this.writingArchive = true;
					this.listingArchive = false;
					}
				else if ( ch == 'x' )
					{
					gotOP = true;
					this.writingArchive = false;
					this.listingArchive = false;
					}
				else if ( ch == 't' )
					{
					gotOP = true;
					this.writingArchive = false;
					this.listingArchive = true;
					}
				else if ( ch == 'k' )
					{
					this.keepOldFiles = true;
					}
				else if ( ch == 'b' )
					{
					try {
						int blks = Integer.parseInt( args[ ++idx ] );
						this.blockSize =
							( blks * TarBuffer.DEFAULT_RCDSIZE );
						}
					catch ( NumberFormatException ex )
						{
						ex.printStackTrace( System.err );
						}
					}
				else if ( ch == 'u' )
					{
					this.userName = args[ ++idx ];
					}
				else if ( ch == 'U' )
					{
					String idStr = args[ ++idx ];
					try {
						this.userId = Integer.parseInt( idStr );
						}
					catch ( NumberFormatException ex )
						{
						this.userId = 0;
						ex.printStackTrace( System.err );
						}
					}
				else if ( ch == 'g' )
					{
					this.groupName = args[ ++idx ];
					}
				else if ( ch == 'G' )
					{
					String idStr = args[ ++idx ];
					try {
						this.groupId = Integer.parseInt( idStr );
						}
					catch ( NumberFormatException ex )
						{
						this.groupId = 0;
						ex.printStackTrace( System.err );
						}
					}
				else if ( ch == 'v' )
					{
					this.verbose = true;
					}
				else if ( ch == 'D' )
					{
					this.debug = true;
					}
				else
					{
					System.err.println
						( "unknown option: " + ch );
					this.usage();
					System.exit(1);
					}
				}
			}

		if ( ! gotOP )
			{
			System.err.println
				( "you must specify an operation option (c, x, or t)" );
			this.usage();
			System.exit(1);
			}

		return idx;
		}

	 // I N T E R F A C E   TarProgressDisplay

	 /**
	 * Display progress information by printing it to System.out.
	 */

	public void
	showTarProgressMessage( String msg )
		{
		System.out.println( msg );
		}

	/**
	 * Print version information.
	 */

	private void
	version()
		{
		System.err.println
			( "$Revision: 1.8 $ $Name:  $" );
		}

	/**
	 * Print usage information.
	 */

	private void
	usage()
		{
		System.err.println( "usage: com.ice.tar.tar has three basic modes:" );
		System.err.println( "  com.ice.tar -c [options] archive files..." );
		System.err.println( "    Create new archive containing files." );
		System.err.println( "  com.ice.tar -t [options] archive" );
		System.err.println( "    List contents of tar archive" );
		System.err.println( "  com.ice.tar -x [options] archive" );
		System.err.println( "    Extract contents of tar archive." );
		System.err.println( "" );
		System.err.println( "options:" );
		System.err.println( "   -f file, use 'file' as the tar archive" );
		System.err.println( "   -v, verbose mode" );
		System.err.println( "   -z, use GZIP compression" );
		System.err.println( "   -D, debug archive and buffer operation" );
		System.err.println( "   -b blks, set blocking size to (blks * 512) bytes" );
		System.err.println( "   -u name, set user name to 'name'" );
		System.err.println( "   -U id, set user id to 'id'" );
		System.err.println( "   -g name, set group name to 'name'" );
		System.err.println( "   -G id, set group id to 'id'" );
		System.err.println( "   -?, print usage information" );
		System.err.println( "   --trans, translate 'text/*' files" );
		System.err.println( "   --mime file, use this mime types file and translate" );
		System.err.println( "   --usage, print usage information" );
		System.err.println( "   --version, print version information" );
		System.err.println( "" );
		System.err.println( "The translation options will translate from local line" );
		System.err.println( "endings to UNIX line endings of '\\n' when writing tar" );
		System.err.println( "archives, and from UNIX line endings into loca line endings" );
		System.err.println( "when extracting archives." );
		System.err.println( "" );
		System.err.println( "Copyright (c) 1998,1999 by Tim Endres" );
		System.err.println( "" );
		System.err.println( "This program is free software licensed to you under the" );
		System.err.println( "GNU General Public License. See the accompanying LICENSE" );
		System.err.println( "file, or the webpage <http://www.gjt.org/doc/gpl> or, visit" );
		System.err.println( "visit www.fsf.org for more details." );
		System.err.println( "" );

		this.version();

		System.exit( 1 );
		}

	}