Extracting jar to specified directory

I wanted to extract one of my jars to specified directory using jar command line utility.

If I understand this right -C option should to the trick but when I try

jar xvf myJar.jar -C ./directoryToExtractTo

I am getting usage information from my jar utility, so I am doing something wrong.

Is the thing I want achievable with jar or do I need to manually move my jar and there invoke

jar xvf myJar.jar

jars use zip compression so you can use any unzip utility.

Example:

$ unzip myJar.jar -d ./directoryToExtractTo

It's better to do this.

Navigate to the folder structure you require

Use the command

jar -xvf  'Path_to_ur_Jar_file'

There is no such option available in jar command itself. Look into the documentation:

> -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: jar uf foo.jar -C classes bar.class changes > to the classes directory and add the bar.class from that directory to > foo.jar. The following command, jar uf foo.jar -C classes . -C bin > xyz.class 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. If classes holds files bar1 and bar2, then here's what the > jar file contains using jar tf foo.jar: META-INF/ > > META-INF/MANIFEST.MF > > bar1 > > bar2 > > xyz.class

In case you don't want to change your current working directory, it might be easier to run extract command in a subshell like this.

mkdir -p "/path/to/target-dir"
(cd "/path/to/target-dir" && exec jar -xf "/path/to/your/war-file.war")

You can then execute this script from any working directory.

[ Thanks to David Schmitt for the subshell trick ]

This worked for me.

I created a folder then changed into the folder using CD option from command prompt.

Then executed the jar from there.

d:\LS\afterchange>jar xvf ..\mywar.war

This is what I ended up using inside my .bat file. Windows only of course.

set CURRENT_DIR=%cd%
mkdir ./directoryToExtractTo
cd ./directoryToExtractTo
jar xvf %CURRENT_DIR%\myJar.jar
cd %CURRENT_DIR%

Current working version as of Oct 2020, updated to use maven-antrun-plugin 3.0.0.

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-antrun-plugin</artifactId>
            <version>3.0.0</version>
            <executions>
                <execution>
                    <id>prepare</id>
                    <phase>package</phase>
                    <configuration>
                        <target>
                            <unzip src="target/shaded-jar/shade-test.jar"
                                   dest="target/unpacked-shade/"/>
                        </target>
                    </configuration>
                    <goals>
                        <goal>run</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

Probably a bit of overkill, but this is something I wanted, so I wrote a Bourne Shell script for it (dependencies on sed and grep):

Usage: unjar FILE [DEST]

- DEST must not already exist (won't overwrite existing contents);
  path to DEST will be created.

- If DEST is not provided, defaults to a subdirectory in the current
  working directory that will be named after FILE without the extension.
  Ex: unjar foo.jar  # foo.jar extracted to ./foo

- If DEST is provided, the path will be created and the jar will
  be extracted into it.
  Ex: unjar foo.jar /a/b/c  # foo.jar extracted into /a/b/c

The full script is here at this gist