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# unpack200

Transforms a packed file produced by `pack200`(1) into a JAR file for web deployment.

## Synopsis

unpack200 [ options ] input-file JAR-file

options

  The command-line options. See Options.

input-file

  Name of the input file, which can be a pack200 gzip file or a pack200 file. The input can also be JAR file produced by `pack200`(1) with an effort of `0`, in which case the contents of the input file are copied to the output JAR file with the Pack200 marker.

JAR-file

  Name of the output JAR file.

## Description

The `unpack200` command is a native implementation that transforms a packed file produced by `pack200``(1)` into a JAR file. A typical usage follows. In the following example, the `myarchive.jar` file is produced from `myarchive.pack.gz` with the default `unpack200` command settings.

    unpack200 myarchive.pack.gz myarchive.jar

## Options

-Hvalue --deflate-hint=value

  Sets the deflation to be `true`, `false`, or `keep` on all entries within a JAR file. The default mode is `keep`. If the value is `true` or `false`, then the `--deflate=hint` option overrides the default behavior and sets the deflation mode on all entries within the output JAR file.

-r --remove-pack-file

  Removes the input pack file.

-v --verbose

  Displays minimal messages. Multiple specifications of this option displays more verbose messages.

-q --quiet

  Specifies quiet operation with no messages.

-lfilename --log-file=filename

  Specifies a log file where output messages are logged.

-? -h --help

  Prints help information about the `unpack200` command.

-V --version

  Prints version information about the `unpack200` command.

-Joption

  Passes option to the Java Virtual Machine, where `option` is one of the options described on the reference page for the Java application launcher. For example, `-J-Xms48m` sets the startup memory to 48 MB. See `java`(1).

## Notes

This command should not be confused with the `unpack` command. They are distinctly separate products.

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

## Exit Status

The following exit values are returned: 0 for successful completion, and a value that is greater than 0 when an error occurred.

## See Also

- `pack200`(1)

- `jar`(1)

- `jarsigner`(1)

- Compression Formats for Network Deployment at
  `http://docs.oracle.com/javase/8/docs/technotes/guides/jweb/networking/compression_formats.html`

- The Java SE Technical Documentation page at
  `http://docs.oracle.com/javase/`

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