private Stream resolveTransitiveDependencies()

in arthur-maven-plugin/src/main/java/org/apache/geronimo/arthur/maven/mojo/NativeImageMojo.java [609:657]
45 lines of code
4 McCabe index (conditional complexity)

    private Stream<org.eclipse.aether.artifact.Artifact> resolveTransitiveDependencies(final org.eclipse.aether.artifact.Artifact artifact) {
        final Dependency rootDependency = new Dependency();
        rootDependency.setGroupId(artifact.getGroupId());
        rootDependency.setArtifactId(artifact.getArtifactId());
        rootDependency.setVersion(artifact.getVersion());
        rootDependency.setClassifier(artifact.getClassifier());
        rootDependency.setType(artifact.getExtension());

        final MavenProject fakeProject = new MavenProject();
        fakeProject.setRemoteArtifactRepositories(project.getRemoteArtifactRepositories());
        fakeProject.setSnapshotArtifactRepository(project.getDistributionManagementArtifactRepository());
        fakeProject.setPluginArtifactRepositories(project.getPluginArtifactRepositories());
        fakeProject.getDependencies().add(rootDependency);

        final DependencyResolutionRequest request = new DefaultDependencyResolutionRequest();
        request.setMavenProject(fakeProject);
        request.setRepositorySession(repositorySystemSession);

        final Collection<org.eclipse.aether.artifact.Artifact> artifacts = new ArrayList<>();
        try {
            dependenciesResolver.resolve(request).getDependencyGraph().accept(new DependencyVisitor() {
                @Override
                public boolean visitEnter(org.eclipse.aether.graph.DependencyNode node) {
                    return true;
                }

                @Override
                public boolean visitLeave(org.eclipse.aether.graph.DependencyNode node) {
                    final org.eclipse.aether.artifact.Artifact artifact = node.getArtifact();
                    if (artifact == null) {
                        if (node.getChildren() != null) {
                            node.getChildren().stream()
                                    .map(DependencyNode::getArtifact)
                                    .filter(Objects::nonNull)
                                    .forEach(artifacts::add);
                        } else {
                            getLog().warn(node + " has no artifact");
                        }
                    } else {
                        artifacts.add(artifact);
                    }
                    return true;
                }
            });
            return artifacts.stream().map(NativeImageMojo.this::resolve);
        } catch (final DependencyResolutionException e) {
            throw new IllegalStateException(e.getMessage(), e);
        }
    }