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jar(1)			    General Commands Manual			jar(1)

       jar-The Java Archive Tool

       jar combines multiple files into a single JAR archive file.

	  Create jar file
	     jar  c[v0Mmfe]  [manifest] [jarfile] [entrypoint] [-C dir] input-
	     files [-Joption]

	  Update jar file
	     jar u[v0Mmfe] [manifest] [jarfile] [entrypoint] [-C  dir]	input-
	     files [-Joption]

	  Extract jar file
	     jar x[vf] [jarfile] [inputfiles] [-Joption]

	  List table of contents of jar file
	     jar t[vf] [jarfile] [inputfiles] [-Joption]

	  Add index to jar file
	     jar i jarfile [-Joption]


	     Options that control the jar command.

	     Jar  file	to be created (c), updated (u), extracted (x), or have
	     its table of contents viewed (t).	The  -f	 option	 and  filename
	     jarfile  are  a  pair  --	if  either  is present, they must both
	     appear. Note that omitting f and jarfile  accepts	a  "jar	 file"
	     from  standard  input  (for  x  and t) or sends the "jar file" to
	     standard output (for c and u).

	     Files or directories, separated by spaces, to  be	combined  into
	     jarfile  (for c and u), or to be extracted (for x) or listed (for
	     t) from jarfile. All directories are processed  recursively.  The
	     files are compressed unless option 0 (zero) is used.

	     Pre-existing  manifest  file  whose  name:	 value pairs are to be
	     included in MANIFEST.MF in the jar file. The -m option and	 file-
	     name  manifest are a pair -- if either is present, they must both
	     appear. The letters m, f and e must appear in the same order that
	     manifest, jarfile, entrypoint appear.

	     The name of the class that set as the application entry point for
	     stand-alone applications bundled into executable jar file. The -e
	     option  and  entrypoint  are a pair -- if either is present, they
	     must both appear. The letters m, f and e must appear in the  same
	     order that manifest, jarfile, entrypoint appear.

	  -C dir
	     Temporarily  changes directories to dir while processing the fol-
	     lowing inputfiles argument. Multiple -C dir inputfiles  sets  are

	     Option  to	 be  passed  into the Java runtime environment. (There
	     must be no space between -J and option).

       The jar tool combines multiple files into a single  JAR	archive	 file.
       jar  is	a general-purpose archiving and compression tool, based on ZIP
       and the ZLIB @
       http://www.gzip.org/zlib/ compression format. However, jar was designed
       mainly package java applets or applications into a single archive. When
       the components of an applet or application (files, images and sounds)
       are combined into a single archive, they can be downloaded by a java
       agent (like a browser) in a single HTTP transaction, rather than
       requiring a new connection for each piece. This dramatically improves
       download times. jar also compresses files and so further improves down-
       load time. In addition, it allows individual entries in a file to be
       signed by the applet author so that their origin can be authenticated.
       The syntax for the jar tool is almost identical to the syntax for the
       tar command. A jar archive can be used as a class path entry, whether
       or not it is compressed.

       Typical usage to combine files into a jar file is:

       % jar cf myFile.jar *.class

       In this example, all the class files in the current directory are
       placed into the file named myFile.jar. The jar tool automatically gen-
       erates a manifest file entry named META-INF/MANIFEST.MF. It is always
       the first entry in the jar file. The manifest file declares meta-infor-
       mation about the archive, and stores that data as name : value pairs.
       Refer to the JAR file specification @
       notes/guides/jar/jar.html#JAR%20Manifest for details explaining how the
       jar tool stores meta-information in the manifest file.

       If a jar file should include name : value pairs contained in an exist-
       ing manifest file, specify that file using the -m option:

       % jar cmf myManifestFile myFile.jar *.class

       An existing manifest file must end with a new line character.  jar does
       not parse the last line of a manifest file if it does not end with a
       new line character.

       Note:  A jar command that specifies cfm on the command line instead of
       cmf (the order of the m and -f options are reversed), the jar command
       line must specify the name of the jar archive first, followed by the
       name of the manifest file:
       % jar cfm myFile.jar myManifestFile *.class

       The manifest is in a text format inspired by RFC822 ASCII format, so it
       is easy to view and process manifest-file contents.

       To extract the files from a jar file, use x:

       % jar xf myFile.jar

       To extract individual files from a jar file, supply their filenames:

       % jar xf myFile.jar foo bar

       Beginning with version 1.3 of the JDK, the jar utility supports
       JarIndex @
       notes/guides/jar/jar.html#JAR_Index, which allows application class
       loaders to load classes more efficiently from jar files. If an applica-
       tion or applet is bundled into multiple jar files,  only the necessary
       jar files will be downloaded and opened to load classes. This perfor-
       mance optimization is enabled by running jar with the -ioption. It will
       generate package location information for the specified main jar file
       and all the jar files it depends on, which need to be specified in the
       Class-Path attribute of the main jar file's manifest.

       % jar i main.jar

       In this example, an INDEX.LIST file is inserted into the META-INF
       directory of main.jar.
       The application class loader uses the information stored in this file
       for efficient class loading.  For details about how location informa-
       tion is stored in the index file, refer to the JarIndex specification.
       To copy directories, first compress files in dir1 to stdout, then
       extract from stdin to dir2 (omitting the -f option from both jar com-

       % (cd dir1; jar c .) | (cd dir2; jar x)

       To review command samples which use jar to opeate on jar files and jar
       file manifests, see Examples, below. Also refer to the jar trail of the
       Java Tutorial @

	  c  Creates a new archive file named jarfile (if f is specified) or
	     to standard output (if f and jarfile are omitted). Add to it the
	     files and directories specified by inputfiles.

	  u  Updates an existing file jarfile (when f is specified) by adding
	     to it files and directories specified by inputfiles. For example:
	     jar uf foo.jar foo.class
	     would add the file foo.class to the existing jar file foo.jar.
	     The -u option can also update the manifest entry, as given by
	     this example:
	     jar umf manifest foo.jar
	     updates the foo.jar manifest with the name : value pairs in mani-

	  x  Extracts files and directories from jarfile (if f is specified)
	     or standard input (if f and jarfile are omitted). If inputfiles
	     is specified, only those specified files and directories are
	     extracted. Otherwise, all files and directories are extracted.
	     The time and date of the extracted files are those given in the

	  t  Lists the table of contents from jarfile (if f is specified) or
	     standard input (if f and jarfile are omitted). If inputfiles is
	     specified, only those specified files and directories are listed.
	     Otherwise, all files and directories are listed.

	  i  Generate index information for the specified jarfile and its
	     dependent jar files. For example:
	     jar i foo.jar

	  would generate an INDEX.LIST file in foo.jar which contains location
	  information for each package in foo.jar and all the jar files speci-
	  fied in the Class-Path attribute of foo.jar. See the index example.

	  f  Specifies the file jarfile to be created (c), updated (u),
	     extracted (x), indexed (i), or viewed (t). The -f option and
	     filename jarfile are a pair -- if present, they must both appear.
	     Omitting f and jarfile accepts a jar file name from stdin(for x
	     and t) or sends jar file to stdout (for c and u).

	  v  Generates verbose output to standard output. Examples shown

	  0  (zero) Store without using ZIP compression.

	  M  Do not create a manifest file entry (for c and u), or delete a
	     manifest file entry if one exists (for u).

	  m  Includes name : value attribute pairs from the specified manifest
	     file manifest in the file at META-INF/MANIFEST.MF. jar adds a
	     name : value pair unless an entry already exists with the same
	     name, in which case jar updates its value.
	     On the command line, the letters m and f must appear in the same
	     order that manifest and jarfile appear. Example use:
	     jar cmf myManifestFile myFile.jar *.class
	     You can add special-purpose name : value attribute pairs to the
	     manifest that aren't contained in the default manifest. For exam-
	     ple, you can add attributes specifying vendor information, ver-
	     sion information, package sealing, or to make JAR-bundled appli-
	     cations executable. See the JAR Files @
	     http://docs.oracle.com/javase/tutorial/deployment/jar/ trail in
	     the Java Tutorial	for examples of using the -m option.

	  e  Sets entrypoint as the application entry point for stand-alone
	     applications bundled into executable jar file. The use of this
	     option creates or overrides the Main-Class attribute value in the
	     manifest file. This option can be used during creation of jar
	     file or while updating the jar file. This option specifies the
	     application entry point without editing or creating the manifest
	     For example, this command creates Main.jar where the Main-Class
	     attribute value in the manifest is set to Main:
	     jar cfe Main.jar Main Main.class
	     The java runtime can directly invoke this application by running
	     the following command:
	     java -jar Main.jar
	     If the entrypoint class name is in a package it may use either a
	     dot (".") or slash ("/") character as the delimiter. For example,
	     if Main.class is in a package called foo the entry point can be
	     specified in the following ways:
	     jar -cfe Main.jar foo/Main foo/Main.class
	     jar -cfe Main.jar foo.Main foo/Main.class
	     Note:  specifying both -m and -e options together when the given
	     manifest also contains the Main-Class attribute results in an
	     ambigous Main.class specification, leading to an error and the
	     jar creation or update operation is aborted.

	  -C dir
	     Temporarily changes directories (cd dir) during execution of the
	     jar command while processing the following inputfiles argument.
	     Its operation is intended to be similar to the -C option of the
	     UNIX tar utility.
	     For example, this command changes to the classes directory and
	     adds the bar.class from that directory to foo.jar:
	     jar uf foo.jar -C classes bar.class
	     This command changes to the classes directory and adds to foo.jar
	     all files within the classes directory (without creating a
	     classes directory in the jar file), then changes back to the
	     original directory before changing to the bin directory to add
	     xyz.class to foo.jar.
	     jar uf foo.jar -C classes . -C bin xyz.class
	     If classes holds files bar1 and bar2, then here's what the jar
	     file will contain using jar tf foo.jar:

	     Pass option to the Java runtime environment, where option is one
	     of the options described on the reference page for the java
	     application launcher. For example, -J-Xmx48M sets the maximum
	     memory to 48 megabytes. It is a common convention for -J to pass
	     options to the underlying runtime environment.

       To shorten or simplify the jar command line, you can specify one or
       more files that themselves contain arguments to the jar command (except
       -J options). This enables you to create jar commands of any length,
       overcoming command line limits imposed by the operating system.

       An argument file can include options and filenames. The arguments
       within a file can be space-separated or newline-separated. Filenames
       within an argument file are relative to the current directory, not rel-
       ative to the location of the argument file. Wildcards (*) that might
       otherwise be expanded by the operating system shell are not expanded.
       Use of the @ character to recursively interpret files is not supported.
       The -J options are not supported because they are passed to the
       launcher, which does not support argument files.

       When executing jar, pass in the path and name of each argument file
       with the @ leading character. When jar encounters an argument beginning
       with the character @, it expands the contents of that file into the
       argument list.
       The example below, classes.list holds the names of files output by a
       find command:

       % find . -name '*.class' -print > classes.list

       You can then execute the jar command on Classes.list by passing it to
       jar using argfile syntax:

       % jar cf my.jar @classes.list

       An argument file can specify a path, but any filenames inside the argu-
       ment file that have relative paths are relative to the current working
       directory, not to the path passed in. Here is an example:
       % jar @path1/classes.list

       To add all the files in a particular directory to an archive (overwrit-
       ing contents if the archive already exists). Enumerating verbosely
       (with the -v option) will tell you more information about the files in
       the archive, such as their size and last modified date.
       % ls
       1.au	     Animator.class    monkey.jpg
       2.au	     Wave.class	       spacemusic.au
       3.au	     at_work.gif

       % jar cvf bundle.jar *
       added manifest
       adding: 1.au(in = 2324) (out= 67)(deflated 97%)
       adding: 2.au(in = 6970) (out= 90)(deflated 98%)
       adding: 3.au(in = 11616) (out= 108)(deflated 99%)
       adding: Animator.class(in = 2266) (out= 66)(deflated 97%)
       adding: Wave.class(in = 3778) (out= 81)(deflated 97%)
       adding: at_work.gif(in = 6621) (out= 89)(deflated 98%)
       adding: monkey.jpg(in = 7667) (out= 91)(deflated 98%)
       adding: spacemusic.au(in = 3079) (out= 73)(deflated 97%)

       If you already have separate subdirectories for images, audio files and
       classes, you can combine them into a single jar file:
       % ls -F
       audio/ classes/ images/

       % jar cvf bundle.jar audio classes images
       added manifest
       adding: audio/(in = 0) (out= 0)(stored 0%)
       adding: audio/1.au(in = 2324) (out= 67)(deflated 97%)
       adding: audio/2.au(in = 6970) (out= 90)(deflated 98%)
       adding: audio/3.au(in = 11616) (out= 108)(deflated 99%)
       adding: audio/spacemusic.au(in = 3079) (out= 73)(deflated 97%)
       adding: classes/(in = 0) (out= 0)(stored 0%)
       adding: classes/Animator.class(in = 2266) (out= 66)(deflated 97%)
       adding: classes/Wave.class(in = 3778) (out= 81)(deflated 97%)
       adding: images/(in = 0) (out= 0)(stored 0%)
       adding: images/monkey.jpg(in = 7667) (out= 91)(deflated 98%)
       adding: images/at_work.gif(in = 6621) (out= 89)(deflated 98%)

       % ls -F
       audio/ bundle.jar classes/ images/

       To see the entry names in the jarfile, use the t option:
       % jar tf bundle.jar

       To add an index file to the jar file for speeding up class loading, use
       the i option.

       If you split the inter-dependent classes for a stock trade application
       into three jar files: main.jar, buy.jar, and sell.jar.

       If you specify the Class-path attribute in the main.jar manifest as:
       Class-Path: buy.jar sell.jar

       then you can use the -i option to speed up the class loading time for
       your application:
       % jar i main.jar

       An INDEX.LIST file is inserted to the META-INF directory. This enables
       the application class loader to download the specified jar files when
       it is searching for classes or resources.

       The Jar Overview @

       The Jar File Specification @

       The JarIndex Spec @

       Jar Tutorial @


				  16 Mar 2012				jar(1)