Is it possible to split maven pom files?

Question

Is it possible to include several smaller pom files to create the parent pom file. (e.g. I would like to split the reporting, build sections into their own poms and include them in the parent pom) for managing them effectively

Answer 1

If you are using Maven 2, you can simply create several parent levels. The first pom.xml (pom1) will define the basic properties (such as repositories for example). The second pom.xml (pom2), which has pom1 as <parent>, will define the reporting information. And so on... Finally, the "real" pom.xml will inherit from the pom2 and will define its own properties.

You can create as many parent levels as you want (of course, it will be harder to maintain if you have 5 parent levels).

Note that Maven 3 talked about introducing the mixin concept, which will allow you to fragment your pom.xml into several files, but it looks like that is not happening now until maven 4

Answer 2

Not quite. You can't include reporting and build sections defined in smaller POMs, you can only inherit them from a parent POM.
If your POM is getting too large, it is possible (and recommended) to arrange your dependencies into logical groups. For example, for a GWT project, you could create a new POM for all of your persistence related to GWT as follows:

<project>
  <groupId>org.yourcompany</groupId>
  <artifactId>gwt-dependencies</artifactId>
  <version>1.0</version>
  <packaging>pom</packaging>
  <dependencies>
    <dependency>
      <groupId>com.google</groupId>
      <artifactId>gwt-user</artifactId>
      <version>2.0.1</version>
    </dependency>
    <dependency>
      <groupId>org.extjs</groupId>
      <artifactId>gxt</artifactId>
      <version>2.1.0</version>
    </dependency>
    <!-- etc -->
  </dependencies>
</project>

These groups can then be included in your main POM.