Maven 2 assembly with dependencies: jar under scop

问题:

I am using maven-assembly plugin to create a jar of my application, including its dependencies as follows:

<assembly>
    <id>macosx</id>
    <formats>
       <format>tar.gz</format>
       <format>dir</format>
    </formats>
    <dependencySets>
        <dependencySet>
            <includes>
                <include>*:jar</include>
            </includes>
            <outputDirectory>lib</outputDirectory>
        </dependencySet>
    </dependencySets>
</assembly>

(I omitted some other stuff that is not related to the question)

So far this has worked fine because it creates a lib directory with all dependencies. However, I recently added a new dependency whose scope is system, and it does not copy it to the lib output directory. i must be missing something basic here, so I call for help.

The dependency that I just added is:

<dependency>
  <groupId>sourceforge.jchart2d</groupId>
  <artifactId>jchart2d</artifactId>
  <version>3.1.0</version>
  <scope>system</scope>
  <systemPath>${project.basedir}/external/jchart2d-3.1.0.jar</systemPath>
</dependency>

The only way I was able to include this dependency was by adding the following to the assembly element:

<files>
    <file>
        <source>external/jchart2d-3.1.0.jar</source>
        <outputDirectory>lib</outputDirectory>
    </file>
</files>

However, this forces me to change the pom and the assembly file whenever this jar is renamed, if ever. Also, it seems just wrong.

I have tried with <scope>runtime</scope> in the dependencySets and <include>sourceforge.jchart2d:jchart2d</include> with no luck.

So how do you include a system scoped jar to your assembly file in maven 2?

Thanks a lot

回答1:

I'm not surprised that system scope dependencies are not added (after all, dependencies with a system scope must be explicitly provided by definition). Actually, if you really don't want to put that dependency in your local repository (for example because you want to distribute it as part of your project), this is what I would do:

• I would put the dependency in a "file system repository" local to the project.

• I would declare that repository in my pom.xml like this:

  <repositories>
    <repository>
      <id>my</id>
      <url>file://${basedir}/my-repo</url>
    </repository>
  </repositories>
  

• I would just declare the artifact without the system scope, this is just a source of troubles:

  <dependency>
    <groupId>sourceforge.jchart2d</groupId>
    <artifactId>jchart2d</artifactId>
    <version>3.1.0</version>
  </dependency>
  

I'm not 100% sure this will suit your needs but I think it's a better solution than using the system scope.

Update: I should have mentioned that in my original answer and I'm fixing it now. To install a third party library in the file-based repository, use install:install-file with the localRepositoryPath parameter:

mvn install:install-file -Dfile=<path-to-file> \
                         -DgroupId=<myGroup> \
                         -DartifactId=<myArtifactId> \
                         -Dversion=<myVersion> \
                         -Dpackaging=<myPackaging> \
                         -DlocalRepositoryPath=<path-to-my-repo>

You can paste this as is in a *nix shell. On windows, remove the "\" and put everything on a single line.

回答2:

Btw you can automate it and make it a part of your maven build. The following will install your jar into your local repository before compilation:

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-install-plugin</artifactId>
            <executions>
                <execution>
                    <id>hack-binary</id>
                    <phase>validate</phase>
                    <configuration>
                        <file>${basedir}/lib/your-lib.jar</file>
                        <repositoryLayout>default</repositoryLayout>
                        <groupId>your-group</groupId>
                        <artifactId>your-artifact</artifactId>
                        <version>0.1</version>
                        <packaging>jar</packaging>
                        <generatePom>true</generatePom>
                    </configuration>
                    <goals>
                        <goal>install-file</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

回答3:

I find easy solution in case you creating jar

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-war-plugin</artifactId>
  <version>2.1.1</version>
  <configuration>
    <webResources>
    <resource>
      <directory>dependencies/mydep</directory>
        <targetPath>WEB-INF/lib</targetPath>
        <filtering>true</filtering>
        <includes>
           <include>**/*.jar</include>
        </includes>
    </resource>
  </webResources>
</configuration>
</plugin>

回答4:

You can also handle this via adding a supplemental dependencySet in your dependencySets.

<dependencySet>
  <scope>system</scope>
  <includes>
    <include>*:jar</include>
  </includes>
  <outputDirectory>lib</outputDirectory>
</dependencySet>

The best thing would be to use a Repository Manager (like Nexus, Artifactory, Archiva) and install this kind of dependency in a particular repository. After that you can use such things as a simple dependency. This will simplify your life.

Docs: https://maven.apache.org/plugins/maven-assembly-plugin/assembly.html

回答5:

A simple solution for this is to add it into local maven repository

One way to do is via mvn install commands as suggested in previous post .

Another easy way is , 1) In your eclipse ide right click on project select Maven option . 2) Select Install or deploy an artifact to a maven repository option and click on next. 3)Click on browse next to the Artifact file checkbox & select your jar file 4)Enter the GroupId and ArtifactId and version ensure generate pom & create checksum are checked & packaging is jar

Click on finish ,Wallah !!! your job is done the jar is added in your local repository which you can define in setting.xml or m2 directory

Now just add the simple maven dependency as per the GroupId,ArtifactId & jar version that you have entered as per the import and that's it your external jar will be packaged by maven.

回答6:

Edited: Sorry that i didn't realize alx also mentioned about the clean life cycle workaround.

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-install-plugin</artifactId>
    <executions>
        <execution>
            <id>hack-binary</id>
            <phase>clean</phase>
            <configuration>
                <file>${basedir}/lib/your-lib.jar</file>
                <repositoryLayout>default</repositoryLayout>
                <groupId>your-group</groupId>
                <artifactId>your-artifact</artifactId>
                <version>0.1</version>
                <packaging>jar</packaging>
                <generatePom>true</generatePom>
            </configuration>
            <goals>
                <goal>install-file</goal>
            </goals>
        </execution>
    </executions>
</plugin>

Base on the solution provided by alx, you can execute the install file step at clean phase. but since the clean phase is not in the default life cycle, you have to execute mvn clean at the first time to ensure the jar is ready in the local repo.

ex: mvn clean; mvn package

回答7:

it has worked in a easier way on my solution :

remove from your dependency :

<dependency>
  <groupId>tiago.medici</groupId>
  <artifactId>eureka</artifactId>
  <version>0.0.1</version>
</dependency> 

Then add the maven-install-plugin in the pom.xml as well.

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-install-plugin</artifactId>
  <executions>
    <execution>
      <id>install-external</id>
      <phase>clean</phase>
      <configuration>
        <file>${basedir}/external/tiago.medici-0.0.1.jar</file>
        <repositoryLayout>default</repositoryLayout>
        <groupId>tiago.medici</groupId>
        <artifactId>eureka</artifactId>
        <version>0.0.1</version>
        <packaging>jar</packaging>
        <generatePom>true</generatePom>
      </configuration>
      <goals>
        <goal>install-file</goal>
      </goals>
    </execution>
  </executions>
</plugin>