JAR

What is JAR?

JAR is a PC file archiver that compresses files into a disk-space-saving archive using state of the art archiver technology. It is fast, powerful, reliable, and has a rich set of features (see below).

JAR has a similar command and option feature set to the PC archiver ARJ, but it is not archive compatible with ARJ. JAR comes in a 16 bit DOS version and a 32 bit Windows version.

JAR is not related to the special ZIP archive scheme (Java ARchive) developed by Sun Microsystems.

The Advantages of JAR:

• Year 2000 compliance
• Compatible with DOS or Windows 9x, Me, 2K, XP, and NT
• Supports long filenames in Windows 9x, Me, 2K, XP, and NT
• File version management
• Ranks as one of the best in compression in terms of size reduction of the leading archivers
• Ability to process and archive more than 50,000 files at a time
• Ability to store multiple backups in the same archive using incremental compression
• Support of ANSI style comments
• MS-DOS international language support for the proper casing of filenames
• Supports nested response files
• Archives that can span diskettes
• Built-in facility to recover files from broken archives
• Optional long filenames translation into short names when extracting files in DOS

Please note that JAR version 1.02 does not support self-extracting archives. This feature is no longer a planned enhancement.

Product Comparisons

We compared JAR with some of the leading commercial archivers: PKZIP 2.04g, UltraCompressor II Revision 3, RAR 2.00 BETA for Win32. LHA 2.X and ARJ 2.x are not included because their compression size numbers are very similar to those of PKZIP 2.04g.

COMPUTER:
Pentium-100, 8 MB memory, no external cache, operating system: Windows 95. Additional specific information is included in the file jar.doc.

FILE SET:
The Calgary Corpus
(18 files totaling 3,251,493 bytes, popular file set used to compression rates.)

Archiver	Method	Compression Time	Compressed Size
JAR32	Default	22s	914,020 (100%)
RAR 2.00 beta 3	Default solid	55s	997,418 (109%)
UC2 rev 3	Default	44s	1,051,516 (115%)
PKZIP 2.04	Default	17s	1,074,550 (118%)

 

FILE SET:
ftp.microsoft.com/developr/drg/OLE-info/COMSpecification/COM_Spec_DOC.ZIP
(15 files totaling 1,911,296 bytes, microsoft Word documents.)

Archiver	Method	Compression Time	Compressed Size
JAR32	Default	12s	386,532 (100%)
RAR 2.00 beta 3	Default solid	23s	433,214 (112%)
UC2 rev 3	Default	20s	504,304 (130%)
PKZIP 2.04	Default	8s	544,568 (141%)

 

FILE SET:
Microsoft Visual C++ 1.52
(462 files and directories totaling 18,806,153 bytes, mix of executables, text, DLLs and object files.)

Archiver	Method	Compression Time	Compressed Size
JAR32	Default	177s	7,221,727 (100%)
RAR 2.00 beta 3	Default solid	300s	7,856,362 (109%)
UC2 rev 3	Default	282s	8,556,558 (118%)
PKZIP 2.04	Default	96s	8,945,476 (124%)

 

Archiver	Method	Compression Time	Compressed Size
JAR32	Maximum	264s	5,984,311 (83%)
PKZIP 2.04	Default	96s	8,945,476 (124%)

JAR is currently available in version 1.02 for MS-DOS, Windows 9x, Windows Me, Windows 2000, Windows XP, and Windows NT.