if (model == null) {
            return "";
        }

        String groupId = model.getGroupId();
        if (groupId == null && model.getParent() != null) {
            groupId = model.getParent().getGroupId();
        }

        String artifactId = model.getArtifactId();

        String version = model.getVersion();
        if (version == null && model.getParent() != null) {

      }
    }
    out.close();

    // Check that source returns the right data
    assertThat(source.read()).isEqualTo(data);

    // Make sure that reset deleted the file
    out.reset();
    if (file != null) {
      assertFalse(file.exists());
    }
  }


  public void testThreshold_resetOnFinalize() throws Exception {
    testThreshold(0, 100, true, true);
    testThreshold(10, 100, true, true);

     *
     * @param modelSource The source of the POM to process, may be {@code null}.
     * @return This request, never {@code null}.
     */
    ModelBuildingRequest setModelSource(ModelSource modelSource);

    /**
     * Gets the POM file of the project to build.
     *
     * @return The POM file of the project or {@code null} if not applicable (i.e. when processing a POM from the
     *         repository).
     */

     *
     * @param message The detail message, may be {@code null}.
     * @param groupId The group id of the unresolvable model, may be {@code null}.
     * @param artifactId The artifact id of the unresolvable model, may be {@code null}.
     * @param version The version of the unresolvable model, may be {@code null}.
     * @param cause The cause, may be {@code null}.
     */
    public UnresolvableModelException(

    static FactoryMethodReturnsNullButNotAnnotated returnsNull() {
      return null;
    }
  }

  static class FactoryMethodReturnsNullAndAnnotated {
    private FactoryMethodReturnsNullAndAnnotated() {}

    public static @Nullable FactoryMethodReturnsNullAndAnnotated returnsNull() {
      return null;
    }
  }

  static class FactoryMethodAcceptsNull {

     * @param type The type of the class realm, must not be {@code null}.
     * @param parent The parent realm for the new realm, may be {@code null}.
     * @param parentImports The packages/types to import from the parent realm, may be {@code null}.
     * @param foreignImports The packages/types to import from foreign realms, may be {@code null}.

        // Default groupId for Maven plugins
        if (groupId == null && artifactId != null && artifactId.startsWith(MAVEN_PLUGIN_PREFIX)) {
            groupId = DEFAULT_MAVEN_PLUGIN_GROUP_ID;
        }

        return (groupId != null && artifactId != null) ? groupId + ":" + artifactId : null;
    }

    private boolean fixRepositoryExpressions(

    public String getDefaultGoal() {
        return getBuild() != null ? getBuild().getDefaultGoal() : null;
    }

    public Plugin getPlugin(String pluginKey) {
        org.apache.maven.api.model.Plugin plugin =
                getBuild().getDelegate().getPluginsAsMap().get(pluginKey);
        return plugin != null ? new Plugin(plugin, getBuild()) : null;
    }

    /**
     * Default toString
     */

        if (composerConfig != null) {
            mojo.setComponentComposer(composerConfig.getValue());
        }

        String since = c.getChild("since").getValue();

        if (since != null) {
            mojo.setSince(since);
        }

        PlexusConfiguration deprecated = c.getChild("deprecated", false);

        if (deprecated != null) {

        if (repositories != null && mirrors != null) {
            for (ArtifactRepository repository : repositories) {
                Mirror mirror = MavenRepositorySystem.getMirror(repository, mirrors);
                injectMirror(repository, mirror);
            }
        }
    }

    private void injectMirror(ArtifactRepository repository, Mirror mirror) {
        if (mirror != null) {