Apache Maven Dependency Plugin – Copying specific artifacts

Copying specific artifacts

In copying specific artifacts, you need to bind the dependency:copy mojo to a lifecycle, configure the plugin and specify the artifacts you want to copy. See the following example:

<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>3.8.1</version>
        <executions>
          <execution>
            <id>copy</id>
            <phase>package</phase>
            <goals>
              <goal>copy</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <artifactItems>
            <artifactItem>
              <groupId>junit</groupId>
              <artifactId>junit</artifactId>
              <version>3.8.1</version>
              <type>jar</type>
              <overWrite>false</overWrite>
              <outputDirectory>${project.build.directory}/alternateLocation</outputDirectory>
              <destFileName>optional-new-name.jar</destFileName>
            </artifactItem>
          </artifactItems>
          <outputDirectory>${project.build.directory}/wars</outputDirectory>
          <overWriteReleases>false</overWriteReleases>
          <overWriteSnapshots>true</overWriteSnapshots>
        </configuration>
      </plugin>
    </plugins>
  </build>
  [...]
</project>

Then after executing mvn package, the artifact (junit) is copied to the given alternate location.

Artifacts are resolved from the following sources in order:

the current reactor,
the local repository,
the configured remote repositories.

If the artifact cannot be resolved from the above sources then the build will fail.

If the artifact is also listed as a dependency, the version of the artifactItem will default to the version from the dependencies or dependencyManagement, e.g.

<project>
  [...]
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>3.8.1</version>
        <executions>
          <execution>
            <id>copy</id>
            <phase>package</phase>
            <goals>
              <goal>copy</goal>
            </goals>
            <configuration>
              <artifactItems>
                <artifactItem>
                  <groupId>junit</groupId>
                  <artifactId>junit</artifactId>
                  <overWrite>false</overWrite>
                  <outputDirectory>${project.build.directory}/alternateLocation</outputDirectory>
                  <destFileName>optional-new-name.jar</destFileName>
                </artifactItem>
              </artifactItems>
              <outputDirectory>${project.build.directory}/wars</outputDirectory>
              <overWriteReleases>false</overWriteReleases>
              <overWriteSnapshots>true</overWriteSnapshots>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  [...]
</project>

The dependency:copy goal can also be used to copy the just built artifact to a custom location if desired. It must be bound to any phase after the package phase so that the artifact exists in the repository. The following configuration shows how (binding to the install phase in this case):

<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>3.8.1</version>
        <executions>
          <execution>
            <id>copy-installed</id>
            <phase>install</phase>
            <goals>
              <goal>copy</goal>
            </goals>
            <configuration>
              <artifactItems>
                <artifactItem>
                  <groupId>${project.groupId}</groupId>
                  <artifactId>${project.artifactId}</artifactId>
                  <version>${project.version}</version>
                  <type>${project.packaging}</type>
                </artifactItem>
              </artifactItems>
              <outputDirectory>some-other-place</outputDirectory>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  [...]
</project>

Using an alternate local repository

dependency:copy always downloads artifacts to default local repository first, and then copy the artifacts to the desired locations. For large size unique snapshot artifacts, the downloads can quickly fill up default local repository, and therefore local disk, after many executions. To clean up the downloaded artifacts as part the build, set localRepositoryDirectory's value to a location in your project's target directory.

This use case also applies to dependency:unpack goal.

<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>3.8.1</version>
        <executions>
          <execution>
            <id>copy-with-alternalte-repo</id>
            <phase>install</phase>
            <goals>
              <goal>copy</goal>
            </goals>
            <configuration>
              <artifactItems>
                <artifactItem>
                  [...]
                </artifactItem>
                [...]
              </artifactItems>
              <localRepositoryDirectory>${project.build.directory}/localrepo</localRepositoryDirectory>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  [...]
</project>

Copying from the command line

If you intend to configure this mojo for execution on the command line using:

mvn dependency:copy

you must not put the configuration inside the executions tag. Your configuration should look like this:

<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>3.8.1</version>
        <configuration>
          <artifactItems>
            <artifactItem>
              <groupId>[ groupId ]</groupId>
              <artifactId>[ artifactId ]</artifactId>
              <version>[ version ]</version>
              <type>[ packaging ]</type>
              <overWrite>[ true or false ]</overWrite>
              <outputDirectory>[ output directory ]</outputDirectory>
              <destFileName>[ filename ]</destFileName>
            </artifactItem>
          </artifactItems>
          <!-- other configurations here -->
        </configuration>
      </plugin>
    </plugins>
  </build>
  [...]
</project>