<name>CoreExtension</name>
      <description>Describes a build extension to utilise.</description>
      <version>1.0.0+</version>
      <fields>
        <field>
          <name>groupId</name>
          <description>The group ID of the extension's artifact.</description>
          <version>1.0.0+</version>
          <required>true</required>
          <type>String</type>
        </field>
        <field>

KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<plugin>
  <description>plugin-description</description>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-jar-plugin</artifactId>
  <version>2.3-SNAPSHOT</version>
  <goalPrefix>jar</goalPrefix>
  <isolatedRealm>false</isolatedRealm>
  <inheritedByDefault>true</inheritedByDefault>

  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>inheritance</groupId>
  <artifactId>child</artifactId>
  <version>12-SNAPSHOT</version>

  <!-- name is not inherited, but description is -->
  <description>Model inheritance description</description>

 * to specific minimum versions to work properly with Maven 4.
 *
 * @param groupId the Maven groupId of the plugin
 * @param artifactId the Maven artifactId of the plugin
 * @param minVersion the minimum version required for Maven 4 compatibility
 * @param reason the reason why this plugin needs to be upgraded
 */

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t06-d</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t06-d</artifactId>
  <packaging>jar</packaging>
  <version>1.1</version>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t07-d</artifactId>
  <packaging>jar</packaging>
  <version>1.1</version>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t10-b</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>

<project>
  <parent>
    <artifactId>p0</artifactId>
    <groupId>maven</groupId>
    <version>1.0</version>
    <relativePath>../../pom.xml</relativePath>
  </parent>
  <modelVersion>4.0.0</modelVersion>
  <artifactId>p1</artifactId>

        serializer.startTag(NAMESPACE, tagName);
        if (coreExtension.getGroupId() != null) {
            serializer
                    .startTag(NAMESPACE, "groupId")
                    .text(coreExtension.getGroupId())
                    .endTag(NAMESPACE, "groupId");
        }
        if (coreExtension.getArtifactId() != null) {
            serializer
                    .startTag(NAMESPACE, "artifactId")