Last updated December 16, 2019

Some Java applications have dependencies that aren’t available in a public or private Maven repository (the latter of which can be accessed using a custom settings.xml file). This guide shows you how to add these unmanaged libraries in your application project and tell Maven how to find them.

Pick groupId, artifactId and version parameters

Let’s say your app depends on the library mylib.jar which is not in any public Maven repository. First you must define a groupId, artifactId and version for the library. These parameters may not matter to you, but Maven requires this information for all dependencies.

So let’s use:

• groupId: com.example
• artifactId: mylib
• version: 1.0 (or whatever version your lib is, if you have it versioned)

Create a local Maven repository directory

Your project root should look something like this to start with:

yourproject
+- pom.xml
+- src

Add a standard Maven repository directory called repo for the group com.example and version 1.0:

yourproject
+- pom.xml
+- src
+- repo

Deploy the Artifact Into the Repo

Maven can deploy the artifact for you using the mvn deploy:deploy-file goal:

mvn deploy:deploy-file -Durl=file:///path/to/yourproject/repo/ -Dfile=mylib-1.0.jar -DgroupId=com.example -DartifactId=mylib -Dpackaging=jar -Dversion=1.0

Your project will contain some Maven metadata and your JAR file.

yourproject
+- pom.xml
+- src
+- repo
   +- com
      +- example
         +- mylib
            +- maven-metadata.xml
            +- ...
            +- 1.0
               +- mylib-1.0.jar
               +- mylib-1.0.pom
               +- ...

Update Pom file

Now edit your pom.xml and add this repository to your <repositories/> element. You may have to create the <repositories/> element if you dont have one.

<repositories>
    <!--other repositories if any-->
    <repository>
        <id>project.local</id>
        <name>project</name>
        <url>file:${project.basedir}/repo</url>
    </repository>
</repositories>

When using the repository from a sub-module, you will need to substitute the ${project.parent.baseDir} property in the <url> element.

Now you can add this jar as a dependency as normal:

<dependency>
    <groupId>com.example</groupId>
    <artifactId>mylib</artifactId>
    <version>1.0</version>
</dependency>

Commit to Git

Dont forget to add and commit your local repo folder to git.

$ git add repo
$ git commit -m 'adding project local maven repo, with mylib.jar 1.0'

The next time you push your project the dependency will resolve and your application will build without an issue. Since the local repo folder and jars are checked in with your application code they will remain private to your app.