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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.

Migrate maven project in offline environment

I have created a web application in spring mvc and now i have to migrate the project to an offline machine but when i imported the project in my eclipse(offline) then it got stuck on "Importing Maven Projects" and also it is showing an error in my pom.xml file at tag :-
<plugins>
<plugin> // shows error over here
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
I also read something about mvn dependency:go-offline so I tried it but couldn't exactly understand that where it saves the dependencies?
So, is there a way through which i could import the project in the offline environment?

As pointed out by #Thomas, the only way to build a project which needs external dependencies with Maven is to copy the repository in the target environment. Build your project on an online environment, then copy your .m2 folder in the offline one. The build will then find all required libraries locally.
With mvn dependency:go-offline you tell maven to download all the needed plugin dependencies in your local repository.

Java 9 compiles fine in maven but not in intellij

I wanted to update my project from java 8 to java 10. Hitting the well known problems of java 9 module system. However after some fiddling, researching and back and forth I was able to compile everything in maven. I added a module-info.java to my project. See also this snippet of my pom.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.7.0</version>
<configuration>
<source>10</source>
<target>10</target>
<release>10</release>
<optimize>true</optimize>
<debug>true</debug>
</configuration>
<dependencies>
<dependency>
<groupId>org.ow2.asm</groupId>
<artifactId>asm</artifactId>
<version>6.2</version>
</dependency>
</dependencies>
</plugin>
However Intellij is reporting 100 errors saying
unnamed module ready package X from both A and B
and similar. I'm using Intellij Community Edition 1018.1.5. I tested it in eclipse photon and there it compiles fine. I think that IntelliJ is putting the maven dependencies differently on the module path/classpath than how maven or eclipse puts them.
However, I'm at a loss and have no idea how to convince IntelliJ to compile my project.

I'd prefer to put this in a comment, since I can't really give an answer until I have more info, but you can't add screenshots to comments. In any case, did you tweak the appropriate settings under File > Project Structure > Project as in:
And also under File > Project Structure > Modules:

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.

Jenkins Maven Plugin: Classloading Feature

Good time!
Our team uses Maven. One of the project modules has a plugin (maven-jibx-plugin) that requires (for our use-case) a dependency on a proprietary jar:
<plugin>
<groupId>org.jibx</groupId>
<artifactId>jibx-maven-plugin</artifactId>
<version>${jibx.version}</version>
<executions>
<execution>
<id>main-schemas</id>
<phase>generate-sources</phase>
<goals>
<goal>schema-codegen</goal>
</goals>
<configuration>
<schemaLocation>
...
</schemaLocation>
<includeSchemas>
...
</includeSchemas>
<customizations>
<customization>${basedir}/src/main/resources/customizations/customization.xml
</customization>
</customizations>
<verbose>true</verbose>
</configuration>
</execution>
<execution>
<id>bind</id>
<phase>process-classes</phase>
<goals>
<goal>bind</goal>
</goals>
<configuration>
<schemaBindingDirectory>
${basedir}/src/main/resources/bindings
</schemaBindingDirectory>
<includeSchemaBindings>
<includeSchemaBinding>*.xml</includeSchemaBinding>
</includeSchemaBindings>
</configuration>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>${project.parent.groupId}</groupId>
<artifactId>proprietary-jar</artifactId>
<version>${project.parent.version}</version>
</dependency>
</dependencies>
</plugin>
The problem is when we build the project locally (and even from a command line on the remote machine where jenkins is istalled), everything builds successfully, but when our jenkins instance tries to build it - the build fails with such a message: "Unable to find class 'class-name-from-the-proprietary-jar'". This problem occurred loccally before we added the plugin dependency..
Seems like there is some feature of jenkins maven plugin that do no resolve the plugin dependencies or may be there are some well-known feature of the jenkins maven plugin classloading (JiBX loads proprietary classes with such a construct: SchemaRootBase.class.getClassLoader().loadClass(cname) So that specifing the dependency for the plugin should provide a knowledge for it about the required classes)... Can somebody, please, suggest the workaround?
UPDATE:
it turned out that the jenkins instance's JAVA_HOME variable is set to /usr/java/jdk1.7.0_25, but in my maven-compiler-plugin I have <target>1.6</target>. Could it be that the problem is in the 1.7 java version?

Well, finally I've found an answer! The problem is not actually in Jenkins, but rather in Maven itself.
ATTENTION: the undergoing information is tested only for Maven 2.
It turned out that when you have a multimodule project and several modules use the same plugin (with different dependencies), Maven would get dependencies set for the first plugin (I mean that the plugin is located in the first module, that Maven builds, with this plugin) and use them for other plugins not overriding the dependencies by the local values.
To clarify this lets have an example. Say there are two modules in the maven build - A and B:
<modules>
<module>A</module>
<module>B</module>
</modules>
and the module A has such the code in the pom file:
<plugin>
<dependencies>
<dependency>
<groupId>com.c</groupId>
<artifactId>D-module</artifactId>
<version>1</version>
</dependency>
</dependencies>
<groupId>org.jibx</groupId>
<artifactId>jibx-maven-plugin</artifactId>
<version>${jibx.version}</version>
</plugin>
and the module B has such the code in the pom file:
<plugin>
<dependencies>
<dependency>
<groupId>com.c</groupId>
<artifactId>F-module</artifactId>
<version>1</version>
</dependency>
</dependencies>
<groupId>org.jibx</groupId>
<artifactId>jibx-maven-plugin</artifactId>
<version>${jibx.version}</version>
</plugin>
It turns out that when Maven builds the module B it will use the D-module dependency even though you have specified the F-module dependency.
In our project we made such a workaround: we moved the plugin declaration to the parent pom in a pluginManagement section and declared the D-module and F-module dependencies for the plugin (also removed these dependencies from the local modules). Ok, the code is rather ugly (having child dependencies in the parent pom file), but this works!
If somebody shared this issue and managed to overcome it, please, advice the solution.

Try mvn clean install in your workspace
Then you should have the same error every where. Also try and use the same command line Jenkins is using (if any)