private static final Attributes.Name AUTO_MODULE_NAME = new Attributes.Name("Automatic-Module-Name");

    /**
     * Module information for the path specified at construction time.
     * This map is usually either empty if no module was found, or a singleton map.
     * It may however contain more than one entry if module hierarchy was detected,
     * in which case there is one key per sub-directory.
     *

                        .expectResult(MavenExecutionException.class, "empty reactor"),
                scenario("Excluded aggregator, but selected child")
                        .activeRequiredProjects(MODULE_C_1)
                        .inactiveRequiredProjects(MODULE_C)
                        .expectResult(MavenExecutionException.class, "empty reactor"),

                    return Optional.empty();
                }
            }

            @Override
            public <T> Optional<T> lookupOptional(Class<T> type, String name) {
                try {
                    return Optional.of(injector.getInstance(Key.of(type, name)));
                } catch (DIException e) {
                    return Optional.empty();
                }
            }

     *         restrictions. Otherwise, the restrictions on the returned range will be empty.
     *         </p>
     *         <p>
     *         The recommended version of the returned version range will be the recommended version of
     *         this version range, provided that ranges falls within the intersected restrictions. If
     *         the restrictions are empty, this version range's recommended version is used if it is not

    private static final Attributes.Name AUTO_MODULE_NAME = new Attributes.Name("Automatic-Module-Name");

    /**
     * Module information for the path specified at construction time.
     * This map is usually either empty if no module was found, or a singleton map.
     * It may however contain more than one entry if module hierarchy was detected,
     * in which case there is one key per sub-directory.
     *

                        Stream.of(new ProjectArtifact(project)),
                        // main project artifact if not a pom
                        "pom".equals(project.getPackaging()) ? Stream.empty() : Stream.of(project.getArtifact())),
                // attached artifacts
                project.getAttachedArtifacts().stream());
        return artifacts.map(RepositoryUtils::toArtifact);
    }

    }
    // ------------------------------------------------------------------------
    @Override
    public String toString() {
        if (isEmpty()) {
            return "empty";
        }
        StringBuilder sb = new StringBuilder(512);
        for (MetadataGraphVertex v : vertices) {
            sb.append("Vertex:  ").append(v.getMd().toString()).append('\n');

 *     <li><code>beta</code> or <code>b</code></li>
 *     <li><code>milestone</code> or <code>m</code></li>
 *     <li><code>rc</code> or <code>cr</code></li>
 *     <li><code>snapshot</code></li>
 *     <li><code>(the empty string)</code> or <code>ga</code> or <code>final</code></li>
 *     <li><code>sp</code></li>
 *     </ul>
 *     Unknown qualifiers are considered after known qualifiers, with lexical order (always case insensitive),
 *   </li>

         * If the given {@code paths} argument contains no element, then this method returns an empty string.
         *
         * @param paths the path to format as a string
         * @return the option associated to this path type followed by the given path elements,
         *         or an empty string if there is no path element.
         */
        @Nonnull
        @Override

        assertEquals("1.6", restriction.getUpperBound().toString(), CHECK_UPPER_BOUND);
        assertTrue(restriction.isUpperBoundInclusive(), CHECK_UPPER_BOUND_INCLUSIVE);

        // test restricting empty sets
        range1 = VersionRange.createFromVersionSpec("[,1.1],[1.4,]");
        range2 = VersionRange.createFromVersionSpec("[1.2,1.3]");
        range1 = range1.restrict(range2);