Can I use the path to a Maven dependency as a property?

Solution 1:

Here is a correct implementation, using the maven-dependency-plugin properties goal, which can be used anywhere in a pom:

<?xml version="1.0" encoding="UTF-8"?>
<project>
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.stackoverflow</groupId>
    <artifactId>q2359872</artifactId>
    <version>2.0-SNAPSHOT</version>
    <name>q2359872</name>

    <properties>
        <!-- Must be listed in the dependencies section otherwise it will be null. -->
        <my.lib>${org.jmockit:jmockit:jar}</my.lib>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.jmockit</groupId>
            <artifactId>jmockit</artifactId>
            <version>1.11</version>
        </dependency>
    </dependencies>
    <build>
        <defaultGoal>generate-sources</defaultGoal>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.3</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>properties</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <!-- Example usage: -->
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.2</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>exec</goal>
                        </goals>
                        <phase>generate-sources</phase>
                    </execution>
                </executions>
                <configuration>
                    <executable>echo</executable>
                    <arguments>
                        <argument>path to jar=</argument>
                        <argument>${org.jmockit:jmockit:jar}</argument>
                        <argument>my.lib=</argument>
                        <argument>${my.lib}</argument>
                    </arguments>
                </configuration>
            </plugin>
            <!-- end of Example usage -->
        </plugins>
    </build>
</project>

And the output is...

jpyeron@black /projects/wkspc/tmp/foo
$ /cygdrive/c/programs.x86_64/apache-software-foundation/apache-maven-3.1.1/bin/mvn
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building q2359872 2.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-dependency-plugin:2.3:properties (default) @ q2359872 ---
[INFO]
[INFO] --- exec-maven-plugin:1.2:exec (default) @ q2359872 ---
path to jar= C:\Documents and Settings\jpyeron\.m2\repository\org\jmockit\jmockit\1.11\jmockit-1.11.jar my.lib= C:\Documents and Settings\jpyeron\.m2\repository\org\jmockit\jmockit\1.11\jmockit-1.11.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.032s
[INFO] Finished at: Wed Sep 17 12:07:18 EDT 2014
[INFO] Final Memory: 10M/153M
[INFO] ------------------------------------------------------------------------

Solution 2:

Assuming that the com.foo:Bar:jar:1.2.3 artifact is declared as dependency in your POM, the following property returns the path to the jar in the local repository:

${maven.dependency.com.foo.Bar.jar.path}

Update: Here is a simple POM demonstrating this:

<?xml version="1.0" encoding="UTF-8"?>
<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.stackoverflow</groupId>
  <artifactId>q2359872</artifactId>
  <version>1.0-SNAPSHOT</version>
  <name>q2359872</name>
  <properties>
    <my.lib>${maven.dependency.junit.junit.jar.path}</my.lib>
  </properties>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <artifactId>maven-antrun-plugin</artifactId>
        <executions>
          <execution>
            <phase>process-resources</phase>
            <configuration>
              <tasks>
                <echo>${my.lib}</echo>
              </tasks>
            </configuration>
            <goals>
              <goal>run</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
</project>

Running mvn process-resources produces the following output:

$ mvn process-resources
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Building q2359872
[INFO]    task-segment: [process-resources]
[INFO] ------------------------------------------------------------------------
[INFO] [resources:resources {execution: default-resources}]
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory /home/pascal/Projects/stackoverflow/q2359872/src/main/resources
[INFO] [antrun:run {execution: default}]
[INFO] Executing tasks
     [echo] /home/pascal/.m2/repository/junit/junit/3.8.1/junit-3.8.1.jar
[INFO] Executed tasks
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 7 seconds
[INFO] Finished at: Tue Mar 02 14:41:32 CET 2010
[INFO] Final Memory: 7M/68M
[INFO] ------------------------------------------------------------------------

Solution 3:

There is a plugin which might be what you are looking for... bitstrings.org (home).