assertTrue(low.compareTo(high) < 0, "expected " + low + " < " + high);
                assertTrue(high.compareTo(low) > 0, "expected " + high + " > " + low);
            }
        }
    }

    private void checkVersionsEqual(String v1, String v2) {
        Comparable c1 = newComparable(v1);
        Comparable c2 = newComparable(v2);
        assertEquals(0, c1.compareTo(c2), "expected " + v1 + " == " + v2);

                    || res2.getUpperBound() == null
                    || res1.getLowerBound().compareTo(res2.getUpperBound()) <= 0) {
                if (res1.getUpperBound() == null
                        || res2.getLowerBound() == null
                        || res1.getUpperBound().compareTo(res2.getLowerBound()) >= 0) {
                    ArtifactVersion lower;
                    ArtifactVersion upper;

        return new ExceptionSummary(null, message, null, children);
    }

    private ExceptionSummary handle(ModelProblem problem, String projectId) {
        if (ModelProblem.Severity.ERROR.compareTo(problem.getSeverity()) >= 0) {
            String message = problem.getMessage();

            String location = ModelProblemUtils.formatLocation(problem, projectId);

            if (!location.isEmpty()) {

                versioning.setLastUpdated( v.getLastUpdated() );
            }

            if ( v.getLastUpdated() == null || v.getLastUpdated().length() == 0
                 || versioning.getLastUpdated().compareTo( v.getLastUpdated() ) >= 0 )
            {
                changed = true;
                v.setLastUpdated( versioning.getLastUpdated() );

                if ( versioning.getRelease() != null )
                {

    }

    @Override
    public int compareTo(Artifact a) {
        int result = groupId.compareTo(a.getGroupId());
        if (result == 0) {
            result = artifactId.compareTo(a.getArtifactId());
            if (result == 0) {
                result = type.compareTo(a.getType());
                if (result == 0) {
                    if (classifier == null) {

                String lastUpdated = versioning.getLastUpdated();
                String now = versioningRef.getLastUpdated();
                if (lastUpdated != null && now != null && now.compareTo(lastUpdated) < 0) {
                    getLogger()
                            .warn("The last updated timestamp in " + metadataFile + " refers to the future (now = "
                                    + now

    }

    private boolean hasErrors(List<BuilderProblem> problems) {
        if (problems != null) {
            for (BuilderProblem problem : problems) {
                if (BuilderProblem.Severity.ERROR.compareTo(problem.getSeverity()) >= 0) {
                    return true;
                }
            }
        }

        return false;
    }

    private Settings readSettings(

            this.version = version;
            this.repository = repository;
        }

        boolean isOutdated(String timestamp) {
            return timestamp != null && timestamp.compareTo(this.timestamp) > 0;
        }
    }

    private static class Key {

        private final String groupId;

        private final String artifactId;

        private final String classifier;