return (string == null || string.isEmpty()) ? null : string;
    }

    private static org.apache.maven.artifact.Artifact toArtifact(Dependency dependency) {
        if (dependency == null) {
            return null;
        }

        org.apache.maven.artifact.Artifact result = toArtifact(dependency.getArtifact());
        result.setScope(dependency.getScope());
        result.setOptional(dependency.isOptional());

        this.repoSystem = repoSystem;
        this.dependenciesValidators = dependenciesValidators;
    }

    private Artifact toArtifact(Plugin plugin, RepositorySystemSession session) {
        return new DefaultArtifact(
                plugin.getGroupId(),
                plugin.getArtifactId(),
                null,
                "jar",

    public Path getPathForLocalArtifact(Session session, LocalRepository local, Artifact artifact) {
        InternalSession s = InternalSession.from(session);
        String path = getManager(s, local).getPathForLocalArtifact(s.toArtifact(artifact));
        return local.getPath().resolve(path);
    }

    @Override
    public Path getPathForRemoteArtifact(
            Session session, LocalRepository local, RemoteRepository remote, Artifact artifact) {

    public Path getPathForLocalArtifact(Session session, LocalRepository local, Artifact artifact) {
        InternalSession s = InternalSession.from(session);
        String path = getManager(s, local).getPathForLocalArtifact(s.toArtifact(artifact));
        return local.getPath().resolve(path);
    }

    @Override
    public Path getPathForRemoteArtifact(
            Session session, LocalRepository local, RemoteRepository remote, Artifact artifact) {

    List<org.eclipse.aether.artifact.Artifact> toArtifacts(Collection<Artifact> artifacts);

    org.eclipse.aether.artifact.Artifact toArtifact(Artifact artifact);

    org.eclipse.aether.artifact.Artifact toArtifact(ArtifactCoordinate coord);

    MavenSession getMavenSession();

    RepositorySystemSession getSession();

    @Override
    public void attachArtifact(Project project, Artifact artifact, Path path) {
        getMavenProject(project)
                .addAttachedArtifact(RepositoryUtils.toArtifact(
                        ((DefaultProject) project).getSession().toArtifact(artifact)));
        artifactManager.setPath(artifact, path);
    }

    @Override
    public List<Path> getCompileSourceRoots(Project project, ProjectScope scope) {

    List<org.eclipse.aether.artifact.Artifact> toArtifacts(Collection<Artifact> artifacts);

    org.eclipse.aether.artifact.Artifact toArtifact(Artifact artifact);

    org.eclipse.aether.artifact.Artifact toArtifact(ArtifactCoordinate coord);

    RepositorySystemSession getSession();

    RepositorySystem getRepositorySystem();

        }
        return dep;
    }

    @Override
    public List<org.eclipse.aether.artifact.Artifact> toArtifacts(Collection<Artifact> artifacts) {
        return artifacts == null ? null : map(artifacts, this::toArtifact);
    }

    @Override
    public org.eclipse.aether.artifact.Artifact toArtifact(Artifact artifact) {
        File file = getService(ArtifactManager.class)
                .getPath(artifact)

    @Override
    public List<org.eclipse.aether.artifact.Artifact> toArtifacts(Collection<Artifact> artifacts) {
        return artifacts == null ? null : map(artifacts, this::toArtifact);
    }

    @Override
    public org.eclipse.aether.artifact.Artifact toArtifact(Artifact artifact) {
        File file = getService(ArtifactManager.class)
                .getPath(artifact)

        request.setTrace(RequestTrace.newChild(null, legacySupport.getSession().getCurrentProject()));

        org.eclipse.aether.artifact.Artifact mainArtifact = RepositoryUtils.toArtifact(artifact);
        mainArtifact = mainArtifact.setFile(source);
        request.addArtifact(mainArtifact);

        for (ArtifactMetadata metadata : artifact.getMetadataList()) {