*/
    ArtifactFilter getArtifactFilter();

    /**
     * Returns a filter for only the core artifacts.
     *
     * @return the artifact filter
     */
    ArtifactFilter getCoreArtifactFilter();

    /**
     * Exclude an extension artifact (doesn't affect getArtifactFilter's result, only getExtensionArtifactFilter).
     *
     * @param artifactId an artifact id