Invalid value for finalName in Maven plugin parameter

[Peter Johnson]

I have developed a Maven plugin. One of my mojos has this as a parameter:

  /**
   * @parameter 
   *            default-value="${project.build.directory}/${project.build.finalName}"
   */
  private String inputDirectory;

The pom.xml that includes the plugin in the <build> section has a <finalName> entry, but the plugin reports that inputDirectory was set to "${project.build.directory}/{project.artifactId}" instead. However, if I do this:

      <plugin>
        <groupId>my.group.id</groupId>
        <artifactId>my-xxx-plugin</artifactId>
        <version>9.9.9</version>
        <extensions>true</extensions>
        <configuration>
          <inputDirectory>${project.build.directory}/${project.build.finalName}</inputDirectory>
        </configuration>
      </plugin>

Then inputDirectory is set to "${project.build.directory}/${project.build.finalName}" as expected.

In addition, within the plugin I looked at the value of project.getBuild().getFinalName(), and even that returned artifactId, and not finalName.

So how come finalName == finalName when evaluated within the pom.xml, but finalName != finalName when evaluated within the plugin? Googling didn't yield much help (I came across several defect reports that were variations of this, all claimed to be closed and fixed).

I'm using Maven 3.0.3, and in most cases I am specifying the latest versions of various plugins.