[FIXED] How to copy the dependency jar in a target folder through Maven

Issue

I am trying to make a jar of a project and then copy it to a target folder but it is not working. Below is the POM. 'Maven Install' does create the jar but it doesn't copy it to the lib folder.

pom.xml

<build>
<pluginManagement>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>${java.version}</source>
                <target>${java.version}</target>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-dependency-plugin</artifactId>
            <executions>
                <execution>
                    <id>copy-dependencies</id>
                    <phase>prepare-package</phase>
                    <goals>
                        <goal>copy-dependencies</goal>
                    </goals>
                    <configuration>
                        <outputDirectory>/apps/dislocation/lib</outputDirectory>
                        <overWriteReleases>false</overWriteReleases>
                        <overWriteSnapshots>false</overWriteSnapshots>
                        <overWriteIfNewer>true</overWriteIfNewer>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
    </pluginManagement>
</build>

Solution

Plugins just declared in <pluginManagement> do nothing. This is just a configuration what to do when the plugin is declared elsewhere (in the same or in a module/child POM). You have to have a declaration in <build>/<plugins> somewhere, too:

However, this only configures plugins that are actually referenced within the plugins element in the children or in the current POM.

dependency:copy-dependencies says:

Goal that copies the project dependencies from the repository to a defined location.

That means dependency:copy-dependencies doesn't copy the JAR you create in the project but all that's declared under <dependencies>.

Furhermore, the prepare-package phase comes long before the install phase, even the JAR is only created in the next phase (package) so there wouldn't be anything to copy from the repository – if it were the proper choice – at the prepare-package phase (though there can be an older version of the JAR from a previous mvn install).

So, you might think to add to your POM:

    <dependencies>
        <dependency>
            <groupId>${project.groupId}</groupId>
            <artifactId>${project.artifactId}</artifactId>
            <version>${project.version}</version>
        </dependency>
    </dependencies>

but this gives:

[FATAL] 'dependencies.dependency.[<groupId>:<artifactId>:<version>]'
  for <groupId>:<artifactId>:<version> is referencing itself. @ line ..., column ...

So, you have to use one of those in Best practices for copying files with Maven.

Answered By - Gerold Broser
Answer Checked By - Katrina (JavaFixing Volunteer)