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Excluding certain .jars from a Maven dependency from build by classifier

My project includes the nd4j-native-platform dependency, which includes .jars for windows, linux, and mac. The app is developed on windows/mac machines then deployed to Linux, so I'd like to save space on deployment by excluding these other platform jars that take up > 400 MB when the .war is built. Tl;dr, I want to exclude all the .jars that don't end with linux-x86_64.
Dependency in pom:
<dependency>
<groupId>org.nd4j</groupId>
<artifactId>nd4j-native-platform</artifactId>
<version>1.0.0-beta7</version>
<classifier>linux-x86_64</classifier>
</dependency>
I don't see any way to exclude them by classifier in the dependency tag, it seems you can only exclude by groupId and artifactId. I also tried using packagingExcludes and warSourceExcludes in the .war plugin, but that didn't do anything:
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>3.2.3</version>
<configuration>
<packagingExcludes>
WEB-INF/lib/nd4j-native-1.0.0-beta7-windows-x86_64.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-android-x86.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-macosx-x86_64.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-android-x86_64.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-linux-ppc64le.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-android-arm64.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-android-arm.jar,
WEB-INF/lib/openblas-0.3.9-1-1.5.3-windows-x86_64.jar,
WEB-INF/lib/nd4j-native-1.0.0-beta7-linux-armhf.jar,
WEB-INF/lib/openblas-0.3.9-1-1.5.3-windows-x86.jar,
WEB-INF/lib/openblas-0.3.9-1-1.5.3-windows-x86.jar,
WEB-INF/lib/openblas-0.3.9-1-1.5.3-linux-armhf.jar,
WEB-INF/lib/openblas-0.3.9-1-1.5.3-linux-ppc64le.jar,
WEB-INF/lib/openblas-0.3.9-1-1.5.3-linux-arm64.jar
</packagingExcludes>
</configuration>
</plugin>
Using Maven 3.6.3.

The correct way to deal with this for most things that use JavaCPP is to set the javacpp.platform property.
When building with mvn -Djavacpp.platform=linux-x86_64 you will get only that specific platform and nothing else. This will also apply to all other transitive dependencies, e.g. opencv.
You can try running mvn -Djavacpp.platform=linux-x86_64 dependency:tree to see that it works.

Maven : How to package external jars(folder) in Maven project

I am having a group of external jars(in hundreds) which I have added in the build path of my project to make it work.
But while packaging it is failing as these jar's are not available to maven.
I have gone though many articles and all the solutions(like adding the jar at system path) are for a single jar only.
<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>
Is there any way we can add the group of jars(folder) to the packaging on the project? or any other solution by which my project can build successfully?
can we create a single jar containing all my jars inside and then use the system scope of maven
I have tried creating jar by jar -cvf my_jar.jar * and placed this jar in the system scope. But it does not worked for me.

My solution : Maven pluggin addjar let us add all jar at a place(projectdirectory/lib in this case).
this enables you to add these jar's in the final package(jar in my case) when you maven build, but to run locally you have to add those jar files directly in the classpath.
<plugin>
<groupId>com.googlecode.addjars-maven-plugin</groupId>
<artifactId>addjars-maven-plugin</artifactId>
<version>1.0.5</version>
<executions>
<execution>
<goals>
<goal>add-jars</goal>
</goals>
<configuration>
<resources>
<resource>
<directory>${basedir}/lib</directory>
</resource>
</resources>
</configuration>
</execution>
</executions>
</plugin>
Now create a shade jar using mvn clean install shade:shade

The bad news: For a proper Maven project, you need to add each and every artifact you use as <dependency> in your POM.
The good news: I very much doubt that these 100 jars are all
- directly used in your source code
- not available in a public Maven repository like MavenCentral
So the better strategy would be to figure out what you really need and find that in MavenCentral. Then Maven finds all the transitive dependencies for you. So if you really need 10 of the jars and all other jars are just dependencies of your dependencies, just add these 10 ones (from MavenCentral) and you are done.

Maven project doesn't recognize any classes from included sibling dependency [duplicate]

I am writing a project for acceptance testing and for various reasons this is dependent on another project which is packaged as a WAR. I have managed to unpack the WAR using the maven-dependency-plugin, but I cannot get my project to include the unpacked WEB-INF/lib/*.jar and WEB-INF/classes/* to be included on the classpath so the build fails. Is there a way to include these files into the classpath, or is there a better way of depending on a WAR?
Many thanks.

There's another option since maven-war-plugin 2.1-alpha-2. In your WAR project:
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.1.1</version>
<configuration>
<attachClasses>true</attachClasses>
</configuration>
</plugin>
This creates a classes artifact which you can use in the acceptance tests project with:
<dependency>
<groupId>your-group-id</groupId>
<artifactId>your-artifact-id</artifactId>
<version>your-version</version>
<classifier>classes</classifier>
</dependency>

Indeed, by design, Maven doesn't resolve transitive dependencies of a war declared as dependency of a project. There is actually an issue about that, MNG-1991, but it won't be solved in Maven 2.x and I'm not sure that I don't know if overlays allow to workaround this issue. My understanding of the suggested solution is to duplicate the dependencies, for example in a project of type pom.
(EDIT: After some more digging, I found something interesting in this thread that I'm quoting below:
I have been helping out with the development of the AppFuse project over
the last month where we make heavy use of the war overlay feature in the
Maven war plugin. It is a really nifty feature!
To get max power with war overlays I have developed the Warpath plugin
that allows projects to use war artifacts as fully fledged dependencies.
In brief:
1) The contents of the /WEB-INF/classes directory in the war dependency
artifacts can be included in the project's classpath for normal compile,
etc tasks.
2) Transitive dependencies from the war dependency artifacts become
available for use by other plugins, e.g. compile and ear - so no more
having to include all the dependencies when creating skinny wars!
The plugin has now been actively used in the AppFuse project for the
last few months, and I feel it is at a point where it is both usable and
stable.
Would the war plugin team be interested in including the warpath
functionality inside the war plugin? It would seem to be the most
natural place to host it.
So, I don't have any experience with it, but the maven warpath plugin actually looks nice and simple and is available in the central repo. To use it,include the following plugin configuration element in your pom.xml file:
[...]
<build>
<plugins>
<plugin>
<groupId>org.appfuse</groupId>
<artifactId>maven-warpath-plugin</artifactId>
<version>1.0-SNAPSHOT</version>
<extensions>true</extensions>
<executions>
<execution>
<goals>
<goal>add-classes</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
[...]
And add the war dependencies you want included in the classpath as warpath type dependencies:
[...]
<dependencies>
<dependency>
<groupId>org.appfuse</groupId>
<artifactId>appfuse-web</artifactId>
<version>2.0</version>
<type>war</type>
</dependency>
<dependency>
<groupId>org.appfuse</groupId>
<artifactId>appfuse-web</artifactId>
<version>2.0</version>
<type>warpath</type>
</dependency>
</dependencies>
[...]
Both the war and warpath dependency types are needed: the war type is used by the Maven war plugin to do the war overlay, the warpath type is used by the Warpath plugin to determine the correct list of artifacts for inclusion in the project classpath.
I'd give it a try.)

Use overlays. First, your test project need to have also packaging war.
Declare dependency of war project you want to test:
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>your-project-arftifactId</artifactId>
<version>${project.version}</version>
<type>war</type>
<scope>test</scope>
</dependency>
then configure maven-war-plugin overlay:
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<configuration>
<webResources>
<resource>
<directory>${basedir}/src/main/webresources</directory>
<filtering>true</filtering>
</resource>
</webResources>
<overlays>
<overlay/>
<overlay>
<groupId>your.group</groupId>
<artifactId>your-project-artifactId</artifactId>
</overlay>
</overlays>
</configuration>
</plugin>
In the above example in test project I overwrite webresources configuration files (like conxtext etc.).
EDIT: This solution wasn't tested with Maven 3.

Good point, Justin. That got me actually solving my problem, namely: including a war into an assembly AND including all its transitive dependencies.
I could not duplicate the war-dependency as 'jar' as you suggested since the assembly plugin would not find a jar referenced by that groupId/artefactId, but
duplicating the war-dependency as type pom
works!
The war and its transitive dependencies are not included in the assembly.
To exclude the (now also appearing) pom file I had to add an exclude element like this:
<excludes>
<exclude>*:pom</exclude>
</excludes>
into my assembly.xml file.
I think this could also be a workaround for the original question of this thread.

If you list the dependency on the war project as a jar dependency it seems to pickup the required jars/resources. I'm using Maven 2.2 + m2eclipse.

Non-Maven dependecies in a Maven project

How can I add an external jar file as a dependency for a Maven project in IntelliJ IDEA? Because when I add it in the dependency list and try to compile with Maven, I got an error that that dependency couldn't be found.

You can either
define a system/local dependency like this:
<dependency>
<groupId>example</groupId>
<artifactId>example</artifactId>
<version>1.0.0</version>
<scope>system</scope>
<systemPath>lib/example-1.0.0.jar</systemPath>
</dependency>
As Gimby pointed out, be aware that system dependencies are expected to 'just be there', so they will not be packaged and deployed with your artifact. See this question for reference.
install the artifact into your local repo:
mvn install:install-file -Dfile=<path-to-file> \
-DgroupId=<myGroup> \
-DartifactId=<myArtifactId> \
-Dversion=<myVersion> \
-Dpackaging=<myPackaging> \
-DlocalRepositoryPath=<path-to-my-repo>

Ideally you should deploy the JAR to your repository using mvn deploy:deploy-file.
If that's not possible, you can set the dependencies scope to system and then include a systemPath in the dependency which gives that path to the jar. This is explained in POM Reference - dependencies and comes with a warning that any artifact that depends on the artifact with the system scope dependency will also expect to find the jar via the systemPath.

Step 1: Configure the maven-install-plugin with the goal install-file in your pom.xml
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-install-plugin</artifactId>
<executions>
<execution>
<id>install-external-non-maven-jar-MWS-Client-into-local-maven-repo</id>
<phase>clean</phase>
<configuration>
<repositoryLayout>default</repositoryLayout>
<groupId>com.amazonservices.mws</groupId>
<artifactId>mws-client</artifactId>
<version>1.0</version>
<file>${project.basedir}/lib/MWSClientJavaRuntime-1.0.jar</file>
<packaging>jar</packaging>
<generatePom>true</generatePom>
</configuration>
<goals>
<goal>install-file</goal>
</goals>
</execution>
</executions>
</plugin>
Make sure to edit the file path based on your actual file path (recommended is to place these external non-maven jars inside some folder, let's say lib, and place this lib folder inside your project so as to use project-specific relative path and avoid adding system specific absolute path.
If you have multiple external jars, just repeat the <execution> for other jars within the same maven-install-plugin.
Step 2: Once you have configured the maven-install-plugin as shown above in your pom.xml file, you have to use these jars in your pom.xml as usual:
<dependency>
<groupId>com.amazonservices.mws</groupId>
<artifactId>mws-client</artifactId>
<version>1.0</version>
</dependency>
Note that the maven-install-plugin only copies your external jars to your local .m2 maven repository. That's it. It doesn't automatically include these jars as maven dependencies to your project.
It's a minor point, but sometimes easy to miss.

Custom Maven Plugin: how to add classpaths?

I'm creating a custom plugin for maven. Normally, when you run a normal Java program that depends on some .jar files, you put it in the command line as a classpath. In my plugin, there are some things it needs to know about that are in other .jar files.
When compiling the plugin for maven, how do I add classpaths to my custom maven plugin? Would I add it as a dependency in the pom.xml?

You can add things on the classpath of a plugin via defining dependencies for a plugin which works like this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
<version>2.1</version>
<dependencies>
<dependency>
<groupId>checkstyle</groupId>
<artifactId>checkstyle</artifactId>
<version>4.4</version>
</dependency>
</dependencies>
</plugin>
Apart from that it sounds strange that you need to define dependencies of a plugin during the runtime of the plugin.