pack200

pack200(1)                                                          pack200(1)



NAME
       pack200 - JAR Packing tool

SYNOPSIS
       pack200 [ options ] output-file JAR-file

       Options  may be in any order. The last option on the command line or in
       a properties file supersedes all previously specified options.

          options
             Command-line options.

          output-file
             Name of the output file.

          JAR-file
             Name of the input file.

DESCRIPTION
       The pack200 tool is a Java application that transforms a JAR file  into
       a  compressed  pack200 file using the Java gzip compressor. The pack200
       files are highly compressed files that can be directly deployed, saving
       bandwidth and reducing download time.

       The pack200 tool uses several options to fine-tune and set the compres‐
       sion engine.

   Typical usage:
       % pack200 myarchive.pack.gz myarchive.jar

       In this  example,  myarchive.pack.gz  is  produced  using  the  default
       pack200 settings.

OPTIONS
       -r --repack

          Produces  a JAR file by packing the file myarchive.jar and unpacking
          it. The resulting file can be used as an input to  the  jarsigner(1)
          tool.

             % pack200 --repack myarchive-packer.jar myarchive.jar

             % pack200 --repack myarchive.jar

       -g --no-gzip

          Produces a pack200 file. With this option a suitable compressor must
          be used, and the target  system  must  use  a  corresponding  decom‐
          presser.

             % pack200 --no-gzip myarchive.pack myarchive.jar

       -G --strip-debug

          Strips  attributes used for debugging from the output. These include
          SourceFile, LineNumberTable, LocalVariableTable  and  LocalVariable‐
          TypeTable.  Removing these attributes reduces the size of both down‐
          loads and installations but reduces the usefulness of debuggers.

       -O --no-keep-file-order

          The packer will reorder and transmit all elements. Additionally, the
          packer may remove JAR directory names. This will reduce the download
          size; however, certain JAR file optimizations, such as indexing, may
          not work correctly.

       -Svalue --segment-limit=value

          The  value is the estimated target size N (in bytes) of each archive
          segment. If a single input file requires
          more than N bytes, it will be given its own archive  segment.  As  a
          special case, a value of -1 will produce a single large segment with
          all input files, while a value of 0 will  produce  one  segment  for
          each class. Larger archive segments result in less fragmentation and
          better compression, but processing them requires more memory.

          The size of each segment is estimated by counting the size  of  each
          input  file to be transmitted in the segment, along with the size of
          its name and other transmitted properties.

          The default is 1000000 (a million  bytes).  This  allows  input  JAR
          files  of  moderate  size  to be transmitted in one segment. It also
          puts a limit on memory requirements for packers and unpackers.

          A 10MB JAR packed without this limit will typically pack  about  10%
          smaller,  but  the  packer may require a larger Java heap (about ten
          times the segment limit).

       -Evalue --effort=value

          If the value is set to a single decimal digit, the packer  will  use
          the  indicated  amount of effort in compressing the archive. Level 1
          may produce somewhat larger size and faster compression speed, while
          level  9  will  take much longer but may produce better compression.
          The special value 0 instructs the packer to copy through the  origi‐
          nal  JAR  file  directly  with  no compression. The JSR 200 standard
          requires  any  unpacker  to  understand  this  special  case  as   a
          pass-through of the entire archive.

          The  default is 5, investing a modest amount of time to produce rea‐
          sonable compression.

       -Hvalue --deflate-hint=value

          Overrides the default, which preserves the  input  information,  but
          may  cause the transmitted archive to be larger. The possible values
          are:

          true

          false
             In either case, the packer will set the  deflation  hint  accord‐
             ingly in the output archive, and will not transmit the individual
             deflation hints of archive elements.

          keep
             Preserve deflation hints observed in the input JAR. (This is  the
             default.)

       -mvalue --modification-time=value

          The possible values are:

          latest
             The  packer  will  attempt  to  determine the latest modification
             time, among all the available entries in the original archive, or
             the latest modification time of all the available entries in that
             segment. This single value will be transmitted  as  part  of  the
             segment  and applied to all the entries in each segment. This can
             marginally decrease the transmitted size of the  archive  at  the
             expense of setting all installed files to a single date.

          keep
             Preserves  modification times observed in the input JAR. (This is
             the default.)

       -Pfile --pass-file=file

          Indicates that a file should be passed through bytewise with no com‐
          pression.  By repeating the option, multiple files may be specified.
          There is no pathname transformation, except  that  the  system  file
          separator  is  replaced by the JAR file separator "/". The resulting
          file names must match exactly as strings with their  occurrences  in
          the  JAR  file.  If  file  is a directory name, all files under that
          directory will be passed.

       -Uaction --unknown-attribute=action

          Overrides the default behavior; i.e., the classfile  containing  the
          unknown  attribute will be passed through with the specified action.
          The possible values for actions are:

          error
             The pack200 operation as a whole will fail with a suitable expla‐
             nation.

          strip
             The  attribute  will  be  dropped. Note: Removing the required VM
             attributes may cause Class Loader failures.

          pass
             Upon encountering this attribute, the entire class will be trans‐
             mitted as though it is a resource.

       -Cattribute-name=layout --class-attribute=attribute-name=action
        -Fattribute-name=layout --field-attribute=attribute-name=action
        -Mattribute-name=layout --method-attribute=attribute-name=action
        -Dattribute-name=layout --code-attribute=attribute-name=action

          With  the  above four options, the attribute layout can be specified
          for a class entity, such as Class attribute, Field attribute, Method
          attribute, and Code attribute. The attribute-name is the name of the
          attribute for which the layout or action is being defined. The  pos‐
          sible values for action are:

          some-layout-string
             The layout language is defined in the JSR 200 specification.

          Example: --class-attribute=SourceFile=RUH

          error
             Upon encountering this attribute, the pack200 operation will fail
             with a suitable explanation.

          strip
             Upon encountering this attribute, the attribute will  be  removed
             from  the output. Note: removing VM-required attributes may cause
             Class Loader failures.

          Example: --class-attribute=CompilationID=pass will cause  the  class
          file  containing this attribute to be passed through without further
          action by the packer.

       -f pack.properties --config-file=pack.properties

          A configuration file, containing Java properties to  initialize  the
          packer, may be specified on the command line.

             % pack200 -f pack.properties myarchive.pack.gz myarchive.jar
             % more pack.properties
             # Generic properties for the packer.
             modification.time=latest
             deflate.hint=false
             keep.file.order=false
             # This option will cause the files bearing new attributes to
             # be reported as an error rather than passed uncompressed.
             unknown.attribute=error
             # Change the segment limit to be unlimited.
             segment.limit=-1

          -v --verbose

             Outputs  minimal  messages. Multiple specification of this option
             will output more verbose messages.

          -q --quiet

             Specifies quiet operation with no messages.

          -lfilename --log-file=filename

             Specifies a log file to output messages.

          -Joption

             Passes option to the Java launcher called by pack200.  For  exam‐
             ple,  -J-Xms48m sets the startup memory to 48 megabytes. Although
             it does not begin with  -X,  it  is  not  a  standard  option  of
             pack200.  It is a common convention for -J to pass options to the
             underlying VM executing applications written in Java.

EXIT STATUS
       The following exit values are returned:

           0 for successful completion;

          >0 if an error occurs.

SEE ALSO
          * unpack200 - JAR Unpacking Tool

          * unpack200(1), jar(1), jarsigner(1), attributes(5) man pages

          * Java SE Documentation

          * Java Deployment Guide - Pack200 @
            http://java.sun.com/javase/6/docs/technotes/guides/deploy‐
            ment/deployment-guide/pack200.html

          * jar - Java Archive Tool

          * jarsigner - JAR Signer tool @
            http://java.sun.com/javase/6/docs/technotes/tools/solaris/jar‐
            signer.html


NOTES
       This command should not be confused with pack(1). They are distinctly
       separate products.

       The Java SE API Specification provided with the SDK is the superseding
       authority, in case of discrepancies.

                                  05 Aug 2006                       pack200(1)