assertEquals(-1, problem.getColumnNumber());

        problem = new DefaultProblem(null, null, null, -1, 42, null);
        assertEquals(42, problem.getColumnNumber());

        problem = new DefaultProblem(null, null, null, -1, Integer.MAX_VALUE, null);
        assertEquals(Integer.MAX_VALUE, problem.getColumnNumber());

        // this case is not specified, might also return -1

        if (artifact == null) {
            return null;
        }

        String version = artifact.getVersion();
        if (version == null && artifact.getVersionRange() != null) {
            version = artifact.getVersionRange().toString();
        }

        Map<String, String> props = null;

        // and we want artifact resolution to only return the system scoped artifact itself.
        //
        if (artifact.getScope() != null && artifact.getScope().equals(Artifact.SCOPE_SYSTEM)) {
            return new ResolutionGroup(null, null, null);
        }

        ResolutionGroup cached = cache.get(
                artifact,
                request.isResolveManagedVersions(),

        return treeRoot == null ? null : new MetadataGraph(treeRoot);
    }
    // ----------------------------------------------------------------------------
    public MetadataGraph getGraph(ArtifactScopeEnum scope)
            throws MetadataResolutionException, GraphConflictResolutionException {
        if (treeRoot == null) {
            return null;
        }

        if (conflictResolver == null) {

        this.groupId = (groupId != null && !groupId.isEmpty()) ? groupId : null;
        this.artifactId = (artifactId != null && !artifactId.isEmpty()) ? artifactId : null;
        this.classifier = (classifier != null && !classifier.isEmpty()) ? classifier : null;
        this.extension = (extension != null && !extension.isEmpty()) ? extension : null;

                qualifier = version;
                majorVersion = null;
                minorVersion = null;
                incrementalVersion = null;
                buildNumber = null;
            }
        }
    }

    private static boolean isDigits(String cs) {
        if (cs == null || cs.isEmpty()) {
            return false;
        }
        final int sz = cs.length();

            if (settings.getLocalRepository() != null
                    && !settings.getLocalRepository().isEmpty()) {
                addViolation(problems, BuilderProblem.Severity.WARNING, "localRepository", null, msgS);
            }
            if (!settings.isInteractiveMode()) {
                addViolation(problems, BuilderProblem.Severity.WARNING, "interactiveMode", null, msgS);
            }
            if (settings.isOffline()) {

     *
     * @param groupId The group id, may be {@code null}.
     * @param artifactId The artifact id, may be {@code null}.
     * @param version The version, may be {@code null}.
     * @return The user-friendly artifact id, never {@code null}.
     */
    static String toId(String groupId, String artifactId, String version) {
        return ((groupId != null && !groupId.isEmpty()) ? groupId : "[unknown-group-id]")
                + ':'

        PluginVersionResult result = null;

        if (request.getPom() != null && request.getPom().getBuild() != null) {
            Build build = request.getPom().getBuild();

            result = resolveFromProject(request, build.getPlugins());

            if (result == null && build.getPluginManagement() != null) {

    }

    @Override
    public String getBaseVersion() {
        if (baseVersion == null && version != null) {
            setBaseVersionInternal(version);
        }

        return baseVersion;
    }

    protected String getBaseVersionInternal() {
        if ((baseVersion == null) && (version != null)) {
            setBaseVersionInternal(version);
        }

        return baseVersion;
    }