AspectJ weaving maven modules

Question

I have a project that has multiple maven modules, one of which, contains my aspects. How can I take the aspects and weave multiple maven modules? The documentation for the AspectJ Maven plugin is a little sparse and haven't been able to find many examples.

I have tried putting the aspectj plugin in the parent pom but it doesn't seem to apply the advice for the modules underneath it.

I also tried specifying the aspectsDirectory property but it didn't seem to have any affect. Perhaps I did it wrong?

Answer 1

I think the mechanism is explained pretty well on this page:

Using Aspect Libraries

Basically:

You put all your aspects in one project, compile it using the aspectj-maven-plugin, add a dependency to this project to all projects you want to weave and also add this config to the woven projects:

<plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>aspectj-maven-plugin</artifactId>
    <version>1.3</version>
    <configuration>
        <aspectLibraries>
            <aspectLibrary>
                <groupId>your.aspects.groupId</groupId>
                <artifactId>your.aspects.artifactId</artifactId>
            </aspectLibrary>
        </aspectLibraries>
    </configuration>
    <executions>
        <execution>
            <goals>
                <goal>compile</goal>
            </goals>
        </execution>
    </executions>
</plugin>

The ugly part is: you need to add this configuration to every project, so one possibility would be to use a parent pom. Unfortunately, it would have to be at the same level as the aspects project (because a pom can't define a dependency to a project below it), so you'd have something like this

    ------- root --------
   /                     \
aspects   -------- java-parent ----
         /     /     |      |      \
      java1  java2  java3  java4  java5

or even like this

       ------- root ---------
      /                       \
aspect-parent            --- java-parent ---
  /        \            /     |      |      \
aspects1 aspects2     java1  java2  java3  java4 

You'd add both the <dependency> and the aspectj plugin configuration to the pom of the java-parent project