Hi,
I was refactoring my projects to make better use of dependency management
and pluginManagement. Almost got it all to work the way I want but I hit a
wall in how the pluginManagement is used.
When looking at the definition in the documentation find the following
*pluginManagement: is an element that is seen along side plugins. Plugin
Management contains plugin elements in much the same way, except that rather
than configuring plugin information for this particular project build, it is
intended to configure project builds that inherit from this one. However,
this only configures plugins that are actually referenced within the plugins
element in the children. The children have every right to override
pluginManagement definitions.*
*
*This is all good and actually is exactly the behaviour that I am after...
so after hours of fiddling and looking I was quite pleased to find this
little bit. However when actually applying I find that the plugin
definition in plugin management are actually made active in the CURRENT
project as well as the children. This is quite bothersome unfortunately.
I created a toned downed version of my build situation to illustrate the
issue :
Project A is a generic parent POM that basically just defines the common
parts for all projects.
Project B is a library that is used in many different projects
Project C is an aggregation project as well as parent POM that defines a
framework. There is no code here, just POMs, Assembly descriptors etc. but
the project aggregate many projects to form a single package. I do this to
make it easier to develop against the framework, this way we only inherit
from Project C and all the needed stuff is there that standardizes the
dependencies and packaging of projects built on the framework.
Project D is a project that is built on the framework, a bit of code ans
some stuff to add to the assembly.
OK...
Now, everything is working well and Project C is creating a zip file as it
should that contains all the stuff from modules and dependencies. Now
anyone can download the zip file and start working on the framework. Now I
want to define in the pluginManagement of project C some stuff to help child
projects to use the framework package directly instead of rebuilding it from
scratch everytime. Below is the POM snippet that defines this behaviour :
in Project C I have ...
<build>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.0</version>
<executions>
...
</execution>
</executions>
</plugin>
</plugins>
</pluginManagement>
</build>
if I do mvn help:effective-pom on project C I get that the build section is
empty, which is exactly what I ordered..
If in project D (which has project C as parent) I have the following build
section :
<build>
<plugins>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
</plugin>
</plugins>
</build>
and do a mvn help:effective-pom I get a build section that contains the
maven-dependency-plugin with all the bells and whistle I placed in project`s
C pluginManagement... again all is good...
But let`s say that project C wants to create something that uses
dependencies and needs to do work with the maven-dependency-plugin. I
therefore add the following to Project C POM :
<build>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.0</version>
<executions>
Some stuff for the children
</execution>
</executions>
</plugin>
</plugins>
</pluginManagement>
<plugins>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.0</version>
<inherited>false</inherited> <!-- this perticular config is NOT
for kids... for parent only -->
<executions>
some stuff for adults only
</execution>
</executions>
</plugin>
</plugins>
</build>
now if I do mvn help:effective-pom on project C I get all the stuff for
parent AND all the stuff for kids... Thing is... I don't want the stuff for
kids, I am actually preparing stuff for kids....
I feel this is a bug since the documentation specifically states that the
pluginDependencies are for decendents. Unless they are reffering to the XML
structure's children... in which case there is a terminology problem here
and the documentation should probably changed to specifically state that
children refers to the XML structure... NOT child POMs...
There is a simple solution to this but it involves creating yet another
projects, my project structure is complex enough as it stands adding extra
projects just to ensure maven behaves the way I want will add a lot of
needless cruft in the project tree. Is there a way to get it to do what I
want without resorting to yet-another-project-that-contains-nothing-usefull
(codewise that is)
Thanks
Éric
