org.apache.commons.compress.archivers.sevenz

Class SevenZFileGiveStream

java.lang.Object

org.apache.commons.compress.archivers.sevenz.SevenZFileGiveStream

public class SevenZFileGiveStream
extends java.lang.Object

Reads a 7z file, using RandomAccessFile under the covers.

The 7z file format is a flexible container that can contain many compression and encryption types, but at the moment only only Copy, LZMA2, BZIP2, and AES-256 + SHA-256 are supported, and archive header compression (when it uses the unsupported LZMA compression) isn't. So the only archives that can be read are the following:

 7z a -mhc=off [-mhe=on] -mx=0 [-ppassword] archive.7z files
 7z a -mhc=off [-mhe=on] -m0=LZMA2 [-ppassword] archive.7z files
 7z a -mhc=off [-mhe=on] -m0=BZIP2 [-ppassword] archive.7z files
 

The format is very Windows/Intel specific, so it uses little-endian byte order, doesn't store user/group or permission bits, and represents times using NTFS timestamps (100 nanosecond units since 1 January 1601). Hence the official tools recommend against using it for backup purposes on *nix, and recommend .tar.7z or .tar.lzma or .tar.xz instead.

Both the header and file contents may be compressed and/or encrypted. With both encrypted, neither file names nor file contents can be read, but the use of encryption isn't plausibly deniable.

Constructor Summary

Constructors

Constructor and Description
SevenZFileGiveStream(java.io.File filename)
SevenZFileGiveStream(java.io.File filename, java.lang.String password)

Method Summary

Methods

Modifier and Type	Method and Description
void	close()
java.io.InputStream	getCurrentEntryInputStream()
org.apache.commons.compress.archivers.sevenz.SevenZArchiveEntry	getNextEntry()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)

Methods inherited from class java.lang.Object

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

Constructor Detail

SevenZFileGiveStream

public SevenZFileGiveStream(java.io.File filename,
                    java.lang.String password)
                     throws java.io.IOException

Throws:

java.io.IOException

SevenZFileGiveStream

public SevenZFileGiveStream(java.io.File filename)
                     throws java.io.IOException

Throws:

java.io.IOException

Method Detail

close

public void close()

getNextEntry

public org.apache.commons.compress.archivers.sevenz.SevenZArchiveEntry getNextEntry()
                                                                             throws java.io.IOException

Throws:

java.io.IOException

getCurrentEntryInputStream

public java.io.InputStream getCurrentEntryInputStream()

read

public int read()
         throws java.io.IOException

Throws:

java.io.IOException

read

public int read(byte[] b)
         throws java.io.IOException

Throws:

java.io.IOException

read

public int read(byte[] b,
       int off,
       int len)
         throws java.io.IOException

Throws:

java.io.IOException