com.ice.tar

Class TarArchive


public class TarArchive
extends Object

The TarArchive class implements the concept of a tar archive. A tar archive is a series of entries, each of which represents a file system object. Each entry in the archive consists of a header record. Directory entries consist only of the header record, and are followed by entries for the directory's contents. File entries consist of a header record followed by the number of records needed to contain the file's contents. All entries are written on record boundaries. Records are 512 bytes long. TarArchives are instantiated in either read or write mode, based upon whether they are instantiated with an InputStream or an OutputStream. Once instantiated TarArchives read/write mode can not be changed. There is currently no support for random access to tar archives. However, it seems that subclassing TarArchive, and using the TarBuffer.getCurrentRecordNum() and TarBuffer.getCurrentBlockNum() methods, this would be rather trvial.
Version:
$Revision: 1.15 $
Author:
Timothy Gerard Endres,
See Also:
TarBuffer, TarHeader, TarEntry

Field Summary

protected boolean
asciiTranslate
protected boolean
debug
protected int
groupId
protected String
groupName
protected boolean
keepOldFiles
protected String
pathPrefix
protected TarProgressDisplay
progressDisplay
protected byte[]
recordBuf
protected int
recordSize
protected String
rootPath
protected TarInputStream
tarIn
protected TarOutputStream
tarOut
protected String
tempPath
protected TarTransFileTyper
transTyper
protected int
userId
protected String
userName
protected boolean
verbose

Constructor Summary

TarArchive(InputStream inStream)
The InputStream based constructors create a TarArchive for the purposes of e'x'tracting or lis't'ing a tar archive.
TarArchive(InputStream inStream, int blockSize)
TarArchive(InputStream inStream, int blockSize, int recordSize)
TarArchive(OutputStream outStream)
The OutputStream based constructors create a TarArchive for the purposes of 'c'reating a tar archive.
TarArchive(OutputStream outStream, int blockSize)
TarArchive(OutputStream outStream, int blockSize, int recordSize)

Method Summary

void
closeArchive()
Close the archive.
void
extractContents(File destDir)
Perform the "extract" command and extract the contents of the archive.
int
getGroupId()
Get the group id being used for archive entry headers.
String
getGroupName()
Get the group name being used for archive entry headers.
int
getRecordSize()
Get the archive's record size.
String
getTempDirectory()
Get the current temporary directory path.
int
getUserId()
Get the user id being used for archive entry headers.
String
getUserName()
Get the user name being used for archive entry headers.
boolean
isVerbose()
Returns the verbosity setting.
void
listContents()
Perform the "list" command and list the contents of the archive.
void
setAsciiTranslation(boolean asciiTranslate)
Set the ascii file translation flag.
void
setDebug(boolean debugF)
Set the debugging flag.
void
setKeepOldFiles(boolean keepOldFiles)
Set the flag that determines whether existing files are kept, or overwritten during extraction.
void
setTarProgressDisplay(TarProgressDisplay display)
Set the current progress display interface.
void
setTempDirectory(String path)
Set the current temporary directory path.
void
setTransFileTyper(TarTransFileTyper transTyper)
Set the object that will determine if a file is of type ascii text for translation purposes.
void
setUserInfo(int userId, String userName, int groupId, String groupName)
Set user and group information that will be used to fill in the tar archive's entry headers.
void
setVerbose(boolean verbose)
Set the verbosity flag.
void
writeEntry(TarEntry oldEntry, boolean recurse)
Write an entry to the archive.

Field Details

asciiTranslate

protected boolean asciiTranslate

debug

protected boolean debug

groupId

protected int groupId

groupName

protected String groupName

keepOldFiles

protected boolean keepOldFiles

pathPrefix

protected String pathPrefix

progressDisplay

protected TarProgressDisplay progressDisplay

recordBuf

protected byte[] recordBuf

recordSize

protected int recordSize

rootPath

protected String rootPath

tarIn

protected TarInputStream tarIn

tarOut

protected TarOutputStream tarOut

tempPath

protected String tempPath

transTyper

protected TarTransFileTyper transTyper

userId

protected int userId

userName

protected String userName

verbose

protected boolean verbose

Constructor Details

TarArchive

public TarArchive(InputStream inStream)
The InputStream based constructors create a TarArchive for the purposes of e'x'tracting or lis't'ing a tar archive. Thus, use these constructors when you wish to extract files from or list the contents of an existing tar archive.

TarArchive

public TarArchive(InputStream inStream,
                  int blockSize)

TarArchive

public TarArchive(InputStream inStream,
                  int blockSize,
                  int recordSize)

TarArchive

public TarArchive(OutputStream outStream)
The OutputStream based constructors create a TarArchive for the purposes of 'c'reating a tar archive. Thus, use these constructors when you wish to create a new tar archive and write files into it.

TarArchive

public TarArchive(OutputStream outStream,
                  int blockSize)

TarArchive

public TarArchive(OutputStream outStream,
                  int blockSize,
                  int recordSize)

Method Details

closeArchive

public void closeArchive()
            throws IOException
Close the archive. This simply calls the underlying tar stream's close() method.

extractContents

public void extractContents(File destDir)
            throws IOException,
                   InvalidHeaderException
Perform the "extract" command and extract the contents of the archive.
Parameters:
destDir - The destination directory into which to extract.

getGroupId

public int getGroupId()
Get the group id being used for archive entry headers.
Returns:
The current group id.

getGroupName

public String getGroupName()
Get the group name being used for archive entry headers.
Returns:
The current group name.

getRecordSize

public int getRecordSize()
Get the archive's record size. Because of its history, tar supports the concept of buffered IO consisting of BLOCKS of RECORDS. This allowed tar to match the IO characteristics of the physical device being used. Of course, in the Java world, this makes no sense, WITH ONE EXCEPTION - archives are expected to be propertly "blocked". Thus, all of the horrible TarBuffer support boils down to simply getting the "boundaries" correct.
Returns:
The record size this archive is using.

getTempDirectory

public String getTempDirectory()
Get the current temporary directory path. Because Java's File did not support temporary files until version 1.2, TarArchive manages its own concept of the temporary directory. The temporary directory defaults to the 'user.dir' System property.
Returns:
The current temporary directory path.

getUserId

public int getUserId()
Get the user id being used for archive entry headers.
Returns:
The current user id.

getUserName

public String getUserName()
Get the user name being used for archive entry headers.
Returns:
The current user name.

isVerbose

public boolean isVerbose()
Returns the verbosity setting.
Returns:
The current verbosity setting.

listContents

public void listContents()
            throws IOException,
                   InvalidHeaderException
Perform the "list" command and list the contents of the archive. NOTE That this method uses the progress display to actually list the conents. If the progress display is not set, nothing will be listed!

setAsciiTranslation

public void setAsciiTranslation(boolean asciiTranslate)
Set the ascii file translation flag. If ascii file translatio is true, then the MIME file type will be consulted to determine if the file is of type 'text/*'. If the MIME type is not found, then the TransFileTyper is consulted if it is not null. If either of these two checks indicates the file is an ascii text file, it will be translated. The translation converts the local operating system's concept of line ends into the UNIX line end, '\n', which is the defacto standard for a TAR archive. This makes text files compatible with UNIX, and since most tar implementations for other platforms, compatible with most other platforms.
Parameters:
asciiTranslate - If true, translate ascii text files.

setDebug

public void setDebug(boolean debugF)
Set the debugging flag.
Parameters:
debugF - The new debug setting.

setKeepOldFiles

public void setKeepOldFiles(boolean keepOldFiles)
Set the flag that determines whether existing files are kept, or overwritten during extraction.
Parameters:
keepOldFiles - If true, do not overwrite existing files.

setTarProgressDisplay

public void setTarProgressDisplay(TarProgressDisplay display)
Set the current progress display interface. This allows the programmer to use a custom class to display the progress of the archive's processing.
Parameters:
display - The new progress display interface.

setTempDirectory

public void setTempDirectory(String path)
Set the current temporary directory path.
Parameters:
path - The new temporary directory path.

setTransFileTyper

public void setTransFileTyper(TarTransFileTyper transTyper)
Set the object that will determine if a file is of type ascii text for translation purposes.
Parameters:
transTyper - The new TransFileTyper object.

setUserInfo

public void setUserInfo(int userId,
                        String userName,
                        int groupId,
                        String groupName)
Set user and group information that will be used to fill in the tar archive's entry headers. Since Java currently provides no means of determining a user name, user id, group name, or group id for a given File, TarArchive allows the programmer to specify values to be used in their place.
Parameters:
userId - The user Id to use in the headers.
userName - The user name to use in the headers.
groupId - The group id to use in the headers.
groupName - The group name to use in the headers.

setVerbose

public void setVerbose(boolean verbose)
Set the verbosity flag.
Parameters:
verbose - The new verbosity setting.

writeEntry

public void writeEntry(TarEntry oldEntry,
                       boolean recurse)
            throws IOException
Write an entry to the archive. This method will call the putNextEntry() and then write the contents of the entry, and finally call closeEntry() for entries that are files. For directories, it will call putNextEntry(), and then, if the recurse flag is true, process each entry that is a child of the directory.
Parameters:
recurse - If true, process the children of directory entries.

This software has been placed into the public domain.