/**
     * Shortcut for {@code getService(ArtifactFactory.class).create(...)}.
     *
     * @param groupId the group identifier, or {@code null} is unspecified
     * @param artifactId the artifact identifier, or {@code null} is unspecified
     * @param version the artifact version, or {@code null} is unspecified
     * @param extension the artifact extension, or {@code null} is unspecified

          <defaultValue></defaultValue>
          <identifier>true</identifier>
        </field>
        <field>
          <name>extension</name>
          <version>1.1.0+</version>
          <type>String</type>
          <description>The file extension of the sub-artifact. Each classifier and extension pair may only appear once.</description>
          <identifier>true</identifier>
        </field>
        <field xml.tagName="value">

    private boolean blocked;

    public MavenArtifactRepository() {}

    /**
     * Create a remote download repository.
     *
     * @param id        the unique identifier of the repository
     * @param url       the URL of the repository
     * @param layout    the layout of the repository
     * @param snapshots the policies to use for snapshots

                            "mirrors.mirror.id",
                            null,
                            "must not be 'local'"
                                    + ", this identifier is reserved for the local repository"
                                    + ", using it for other repositories will corrupt your repository metadata.");
                }

        if (repo != null) {
            String id = repo.getId();

            if (id == null || id.isEmpty()) {
                throw new InvalidRepositoryException("Repository identifier missing", "");
            }

            String url = repo.getUrl();

            if (url == null || url.isEmpty()) {
                throw new InvalidRepositoryException("URL missing for repository " + id, id);

            }
        }
        return false;
    }

    /**
     * Searches an artifact of the given group and artifact identifiers, and returns its path
     *
     * @param group the group identifier to search
     * @param artifact the artifact identifier to search
     * @return path to the desired artifact, or {@code null} if not found
     */

            }
        }

        if (!collisions.isEmpty()) {
            throw new DuplicateProjectException(
                    "Two or more projects in the reactor"
                            + " have the same identifier, please make sure that <groupId>:<artifactId>:<version>"
                            + " is unique for each project: " + collisions,
                    collisions);
        }

        return index;
    }

            }
        }
        return false;
    }

    /**
     * Searches an artifact of the given group and artifact identifiers, and returns its path
     *
     * @param group the group identifier to search
     * @param artifact the artifact identifier to search
     * @return path to the desired artifact, or {@code null} if not found
     */

   |
   | Default: false
  <offline>false</offline>
  -->

  <!-- pluginGroups
   | This is a list of additional group identifiers that will be searched when resolving plugins by their prefix, i.e.
   | when invoking a command line like "mvn prefix:goal". Maven will automatically add the group identifiers
   | "org.apache.maven.plugins" and "org.codehaus.mojo" if these are not already contained in the list.
   |-->
  <pluginGroups>

      ]]></description>
      <fields>
        <field>
          <name>id</name>
          <version>1.0.0</version>
          <description><![CDATA[
            A unique identifier for a repository.
          ]]></description>
          <type>String</type>
        </field>
        <field>
          <name>name</name>
          <version>1.0.0</version>
          <description><![CDATA[