Building a WAR project with unzipped JAR dependency? - maven-2

Question

I have two projects, my-lib and my-webapp. The first project is a dependency of my-webapp. Thus, when ask Maven2 to build my WAR, the my-lib JAR is added in the WEB-INF/lib/ directory of the web application.
However, I want to have the my-lib JAR unzipped directly in the WEB-INF/classes directory, exactly as if the my-lib sources were contained in the project my-webapp.
In others words, instead of having the following WAR content:
my-webapp/
...
WEB-INF/
lib/
my-lib-1.0.jar
... (others third libraries)
I want to have that:
my-webapp/
...
WEB-INF/
classes/
my-lib files
lib/
... (others third libraries)
Is there a way to configure the my-webapp or the Maven2 war plugin to achieve that?

Answer 1

As blaufish's answer says, you can use the maven-dependency-plugin's unpack mojo to unpack an artifact. However to avoid the jar appearing in WEB-INF/lib, you need to not specify it as a dependency, and instead configure the plugin to unpack specific artifacts.
The following configuration will unpack the contents of some.group.id:my-lib:1.0:jar into target/classes during the process-resources phase, even if the artifact is not defined as a dependency. Be careful when doing this though as there is potential to clobber your actual content, this can cause much debugging.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>unpack-my-lib</id>
<phase>process-resources</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>some.group.id</groupId>
<artifactId>my-lib</artifactId>
<version>1.0</version>
<type>jar</type>
<overWrite>false</overWrite>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.outputDirectory}</outputDirectory>
<overWriteReleases>false</overWriteReleases>
</configuration>
</execution>
</executions>
</plugin>

Answer 2

You can configure the maven-dependency-plugin to just do that, unpack instead of copying a jar as explained here.
<project>
[...]
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.5.1</version>
<executions>
<execution>
<id>unpack</id>
<phase>package</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<type>jar</type>
<overWrite>false</overWrite>
<outputDirectory>${project.build.directory}/alternateLocation</outputDirectory>
<destFileName>optional-new-name.jar</destFileName>
<includes>**/*.class,**/*.xml</includes>
<excludes>**/*test.class</excludes>
</artifactItem>
</artifactItems>
<includes>**/*.java</includes>
<excludes>**/*.properties</excludes>
<outputDirectory>${project.build.directory}/wars</outputDirectory>
<overWriteReleases>false</overWriteReleases>
<overWriteSnapshots>true</overWriteSnapshots>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
[...]
</project>

Answer 3

The unpack mojo seems to be close to what you are aiming for. Not sure how to complete the entire flow you are proposing though.
(btw, I am doubtful if this a good idea. utility classes should go into jars, and the jars are put either in the WAR or io the EAR. Unpacking utility jars seems wrong)

Answer 4

I was able to use the unpack mojo as described above, plus I marked the dependency itself as "provided" (scope) to avoid duplicating the jar contents under WEB-INF/lib.

Answer 5

[Oops, just realized that you were using Maven. I don't delete this answer because it may come to the rescue of some Ant user. So there's no need to mod me down...]
How many times to I have to mention that Jar, War and Ear Ant tasks are subtasks of the Zip one? :-) If I remember correctly, something like this would do the trick:
<war dist="my-webapp.war">
<zipgroupfileset dir="libs" includes="*.jar" prefix="WEB-INF/classes"/>
</war>
Also worth a trial is with src="mylib.jar" but I haven't tested this option.