How to add local jar files to a Maven project?

Firstly, I would like to give credit for this answer to an anonymous Stack Overflow user - I am pretty sure I've seen a similar answer here before - but now I cannot find it.

The best option for having local JAR files as a dependency is to create a local Maven repository. Such a repository is nothing more than a proper directory structure with pom files in it.

For my example: I have my master project on ${master_project} location and subproject1 is on ${master_project}/${subproject1}.

Then I create a Maven repository in: ${master_project}/local-maven-repo.

In the pom file in subproject1 located at ${master_project}/${subproject1}/pom.xml, the repository needs to be specified which would take file path as a URL parameter:

<repositories>
    <repository>
        <id>local-maven-repo</id>
        <url>file:///${project.parent.basedir}/local-maven-repo</url>
    </repository>
</repositories>

The dependency can be specified as for any other repository. This makes your pom repository independent. For instance, once the desired JAR is available in Maven central, you just need to delete it from your local repo and it will be pulled from the default repo.

    <dependency>
        <groupId>org.apache.felix</groupId>
        <artifactId>org.apache.felix.servicebinder</artifactId>
        <version>0.9.0-SNAPSHOT</version>
    </dependency>

The last but not least thing to do is to add the JAR file to local repository using -DlocalRepositoryPath switch like so:

mvn org.apache.maven.plugins:maven-install-plugin:2.5.2:install-file  \
    -Dfile=/some/path/on/my/local/filesystem/felix/servicebinder/target/org.apache.felix.servicebinder-0.9.0-SNAPSHOT.jar \
    -DgroupId=org.apache.felix -DartifactId=org.apache.felix.servicebinder \
    -Dversion=0.9.0-SNAPSHOT -Dpackaging=jar \
    -DlocalRepositoryPath=${master_project}/local-maven-repo

Once the JAR file is installed, your Maven repo can be committed to a code repository, and the whole set-up is system independent. (Working example in GitHub).

I agree that having JARs committed to source code repo is not a good practice, but in real life, quick and dirty solutions are sometimes better than a full blown Nexus repo to host one JAR that you cannot publish.

Install the JAR into your local Maven repository (typically .m2 in your home folder) as follows:

mvn install:install-file \
   -Dfile=<path-to-file> \
   -DgroupId=<group-id> \
   -DartifactId=<artifact-id> \
   -Dversion=<version> \
   -Dpackaging=<packaging> \
   -DgeneratePom=true

Where each refers to:

<path-to-file>: the path to the file to load e.g → c:\kaptcha-2.3.jar

<group-id>: the group that the file should be registered under e.g → com.google.code

<artifact-id>: the artifact name for the file e.g → kaptcha

<version>: the version of the file e.g → 2.3

<packaging>: the packaging of the file e.g. → jar

Reference

• Maven FAQ: I have a jar that I want to put into my local repository. How can I copy it in?
• Maven Install Plugin Usage: The install:install-file goal

You can add local dependencies directly (as mentioned in build maven project with propriatery libraries included) like this:

<dependency>
    <groupId>com.sample</groupId>
    <artifactId>sample</artifactId>
    <version>1.0</version>
    <scope>system</scope>
    <systemPath>${project.basedir}/src/main/resources/Name_Your_JAR.jar</systemPath>
</dependency>

Update

In new releases this feature is marked as deprecated but still working and not removed yet ( You just see warning in the log during maven start). An issue is raised at maven group about this https://issues.apache.org/jira/browse/MNG-6523 ( You can participate and describe why this feature is helpful in some cases). I hope this feature remains there!

If you are asking me, as long as the feature is not removed, I use this to make dependency to only one naughty jar file in my project which is not fit in repository. If this feature is removed, well, there are lots of good answers here which I can chose from later!