org.eclipse.aether.repository.RemoteRepository Java Examples

@Override
public Artifact resolve(Plugin plugin, List<RemoteRepository> repositories, RepositorySystemSession session) throws PluginResolutionException {
    WorkspaceReader wr = session.getWorkspaceReader();
    NbWorkspaceReader nbwr = null;
    if (wr instanceof NbWorkspaceReader) {
        nbwr = (NbWorkspaceReader)wr;
        //this only works reliably because the NbWorkspaceReader is part of the session, not a component
        nbwr.silence();
    }
    try {
        return super.resolve(plugin, repositories, session);
    } finally {
        if (nbwr != null) {
            nbwr.normal();
        }
    }
}
 

public List<Version> getAllVersions(String groupId, String artifactId) {
    String repositoryUrl = "http://maven.repo/nexus/content/groups/public";
    RepositorySystem repoSystem = newRepositorySystem();

    RepositorySystemSession session = newSession(repoSystem);
    RemoteRepository central = null;
    central = new RemoteRepository.Builder("central", "default", repositoryUrl).build();

    Artifact artifact = new DefaultArtifact(groupId + ":" + artifactId + ":[0,)");
    VersionRangeRequest rangeRequest = new VersionRangeRequest();
    rangeRequest.setArtifact(artifact);
    rangeRequest.addRepository(central);
    VersionRangeResult rangeResult;
    try {
        rangeResult = repoSystem.resolveVersionRange(session, rangeRequest);
    } catch (VersionRangeResolutionException e) {
        throw new RuntimeException(e);
    }
    List<Version> versions = rangeResult.getVersions().stream()
            .filter(v -> !v.toString().toLowerCase().endsWith("-snapshot"))
            .filter(v -> !groupId.contains("org.springframework") || v.toString().equals("2.0.0.RELEASE"))
            .collect(Collectors.toList());
    logger.info("artifact: {}, Available versions: {}", artifact, versions);
    return versions;
}
 

static List<String> resolveDependencies(String groupId, String artifactId, String version,
		List<BillOfMaterials> boms, List<RemoteRepository> repositories) {
	DependencyResolver instance = instanceForThread.get();
	List<Dependency> managedDependencies = instance.getManagedDependencies(boms, repositories);
	Dependency aetherDependency = new Dependency(new DefaultArtifact(groupId, artifactId, "pom",
			instance.getVersion(groupId, artifactId, version, managedDependencies)), "compile");
	CollectRequest collectRequest = new CollectRequest((org.eclipse.aether.graph.Dependency) null,
			Collections.singletonList(aetherDependency), repositories);
	collectRequest.setManagedDependencies(managedDependencies);
	DependencyRequest dependencyRequest = new DependencyRequest(collectRequest,
			DependencyFilterUtils.classpathFilter(JavaScopes.COMPILE, JavaScopes.RUNTIME));
	try {
		return instance.resolveDependencies(dependencyRequest).getArtifactResults().stream()
				.map(ArtifactResult::getArtifact)
				.map((artifact) -> artifact.getGroupId() + ":" + artifact.getArtifactId())
				.collect(Collectors.toList());
	}
	catch (DependencyResolutionException ex) {
		throw new RuntimeException(ex);
	}
}
 

public static File getSdk(MavenProject project, RepositorySystem repoSystem,
    RepositorySystemSession repoSession, List<RemoteRepository>... repos)
    throws MojoExecutionException {
  Artifact artifact = find(project.getPluginArtifacts(), new Predicate<Artifact>() {
    @Override
    public boolean apply(Artifact artifact1) {
      return artifact1.getArtifactId().equals("gcloud-maven-plugin");
    }
  });

  String version = artifact.getVersion();

  if (version.endsWith("-SNAPSHOT")) {
    String newestVersion = determineNewestVersion(repoSystem, repoSession, repos);
    return getSdk(newestVersion, repoSystem, repoSession, repos);
  }

  return getSdk("1.9.42", repoSystem, repoSession, repos);
}
 

private List<RemoteRepository> getRepositories(Dependency dependency, Version bootVersion,
		List<BillOfMaterials> boms) {
	Map<String, RemoteRepository> repositories = new HashMap<>();
	repositories.put("central", DependencyResolver.mavenCentral);
	String dependencyRepository = dependency.getRepository();
	if (dependencyRepository != null) {
		repositories.computeIfAbsent(dependencyRepository, this::repositoryForId);
	}
	for (BillOfMaterials bom : boms) {
		for (String repository : bom.getRepositories()) {
			repositories.computeIfAbsent(repository, this::repositoryForId);
		}
	}
	if (!bootVersion.getQualifier().getId().equals("RELEASE")) {
		repositories.computeIfAbsent("spring-milestones", this::repositoryForId);
		if (bootVersion.getQualifier().getId().contains("SNAPSHOT")) {
			repositories.computeIfAbsent("spring-snapshots", this::repositoryForId);
		}
	}
	return new ArrayList<>(repositories.values());
}
 

@Test
public void basicPomRepos() throws Exception {
    final BootstrapMavenContext mvn = bootstrapMavenContextWithSettings("custom-settings/pom-repos-mirrored");

    final List<RemoteRepository> repos = mvn.getRemoteRepositories();
    assertEquals(1, repos.size());

    RemoteRepository repo = repos.get(0);
    assertEquals("private-repo", repo.getId());
    assertNull(repo.getProxy());
    assertNotNull(repo.getAuthentication());

    List<RemoteRepository> mirroredRepos = repo.getMirroredRepositories();
    assertNotNull(mirroredRepos);
    assertEquals(MIRRORED.size(), mirroredRepos.size());
    for (RemoteRepository r : mirroredRepos) {
        assertTrue(MIRRORED.containsKey(r.getId()));
        assertEquals(MIRRORED.get(r.getId()), r.getUrl());
    }
}
 

public String resolveDevServerJar() {
    String version = getYawpVersion();
    List<RemoteRepository> allRepos = ImmutableList.copyOf(Iterables.concat(getProjectRepos()));

    ArtifactRequest request = new ArtifactRequest(new DefaultArtifact(YAWP_GROUP_ID, YAWP_DEVSERVER_ARTIFACT_ID, "jar", version), allRepos,
            null);

    ArtifactResult result;
    try {
        result = repoSystem.resolveArtifact(repoSession, request);
    } catch (ArtifactResolutionException e) {
        throw new RuntimeException("Could not resolve DevServer artifact in Maven.");
    }

    return result.getArtifact().getFile().getPath();
}
 

public RemoteRepository buildRemoteRepository(MavenRemoteRepository repo, MavenProxySelector selector, Proxy proxy) throws ArtifactException {
    RemoteRepository.Builder builder = new RemoteRepository.Builder(repo.getName(),
            repo.getType(), repo.getUrl());
    builder.setSnapshotPolicy(new org.eclipse.aether.repository.RepositoryPolicy(repo.getEnableSnapshot() == null ? isSnapshotEnabled() : repo.getEnableSnapshot(),
            repo.getSnapshotUpdatePolicy() == null ? getDefaultSnapshotPolicy() : repo.getSnapshotUpdatePolicy(),
            CHECKSUM_POLICY_WARN));
    builder.setReleasePolicy(new org.eclipse.aether.repository.RepositoryPolicy(repo.getEnableRelease() == null ? isReleaseEnabled() : repo.getEnableRelease(),
            repo.getReleaseUpdatePolicy() == null ? getDefaultReleasePolicy() : repo.getReleaseUpdatePolicy(),
            CHECKSUM_POLICY_WARN));
    try {
        if (selector != null && selector.proxyFor(new URL(repo.getUrl()).getHost())) {
            builder.setProxy(proxy);
        }
    } catch (MalformedURLException ex) {
        throw new ArtifactException(ex.getMessage(), ex);
    }
    return builder.build();
}
 

@Override
public Path resolve(final RepositorySystemSession session, final List<RemoteRepository> repositories, final ArtifactName name) {
    final ArtifactResult result;
    try {
        final ArtifactRequest request = new ArtifactRequest();
        final Artifact defaultArtifact = new DefaultArtifact(name.getGroupId(), name.getArtifactId(), name.getClassifier(), name.getPackaging(), name.getVersion());
        request.setArtifact(defaultArtifact);
        request.setRepositories(repositories);
        result = repoSystem.resolveArtifact(session, request);
    } catch (ArtifactResolutionException e) {
        throw new RuntimeException(e.getMessage(), e);
    }
    if (!result.isResolved()) {
        throw new RuntimeException("Failed to resolve artifact " + name);
    }
    final Artifact artifact = result.getArtifact();
    final File artifactFile;
    if (artifact == null || (artifactFile = artifact.getFile()) == null) {
        throw new RuntimeException("Failed to resolve artifact " + name);
    }
    return artifactFile.toPath();
}
 

@Override
public DependencyNode resolve(Plugin plugin, Artifact pluginArtifact, DependencyFilter dependencyFilter, List<RemoteRepository> repositories, RepositorySystemSession session) throws PluginResolutionException {
    
    WorkspaceReader wr = session.getWorkspaceReader();
    NbWorkspaceReader nbwr = null;
    if (wr instanceof NbWorkspaceReader) {
        nbwr = (NbWorkspaceReader)wr;
        //this only works reliably because the NbWorkspaceReader is part of the session, not a component
        nbwr.silence();
    }
    try {
        return super.resolve(plugin, pluginArtifact, dependencyFilter, repositories, session);
    } finally {
        if (nbwr != null) {
            nbwr.normal();
        }
    }
}
 

public static File getSdk(MavenProject project, RepositorySystem repoSystem, RepositorySystemSession repoSession, List<RemoteRepository>... repos)
        throws MojoExecutionException {
  Artifact artifact = (Artifact) find(project.getPluginArtifacts(), new Predicate<Artifact>() {
    @Override
    public boolean apply(Artifact artifact1) {
      return (artifact1.getArtifactId().equals("appengine-maven-plugin")
              && artifact1.getGroupId().equals("com.google.appengine"));
    }
  });

  String version = artifact.getVersion();
  
  if(version.endsWith("-SNAPSHOT")) {
    String newestVersion = determineNewestVersion(repoSystem, repoSession, repos);
    return getSdk(newestVersion, repoSystem, repoSession, repos);
  }

  return getSdk(version, repoSystem, repoSession, repos);
}
 

private static void addProfileRepos(final org.apache.maven.model.Profile profile, final List<RemoteRepository> all) {
    final List<org.apache.maven.model.Repository> repositories = profile.getRepositories();
    for (org.apache.maven.model.Repository repo : repositories) {
        final RemoteRepository.Builder repoBuilder = new RemoteRepository.Builder(repo.getId(), repo.getLayout(),
                repo.getUrl());
        org.apache.maven.model.RepositoryPolicy policy = repo.getReleases();
        if (policy != null) {
            repoBuilder.setReleasePolicy(toAetherRepoPolicy(policy));
        }
        policy = repo.getSnapshots();
        if (policy != null) {
            repoBuilder.setSnapshotPolicy(toAetherRepoPolicy(policy));
        }
        all.add(repoBuilder.build());
    }
}
 

@Test
// SWARM-1173: swarm-plugin trying to download SNAPSHOTs from Maven Central
public void propagateRepositoryPolicies() {
    MavenArtifactResolvingHelper artifactResolverHelper = new MavenArtifactResolvingHelper(null, null, sessionMock, null);
    ArtifactRepositoryPolicy testSnapshotPolicy = new ArtifactRepositoryPolicy(false, "hourly", "warn");
    ArtifactRepositoryPolicy testReleasesPolicy = new ArtifactRepositoryPolicy(true, "never", "warn");
    ArtifactRepository testingRepo = new MavenArtifactRepository("testing-repo", "http://testing-repo.org", new DefaultRepositoryLayout(), testSnapshotPolicy, testReleasesPolicy);
    artifactResolverHelper.remoteRepository(testingRepo);

    List<RemoteRepository> remoteRepos = artifactResolverHelper.getRemoteRepositories();

    Assert.assertTrue("Remote repositories " + remoteRepos + " do not contain expected testing repo " + testingRepo,
                      remoteRepos.stream().anyMatch(
                              remoteRepo -> {
                                  RepositoryPolicy snapshotsPolicy = remoteRepo.getPolicy(true);
                                  RepositoryPolicy releasesPolicy = remoteRepo.getPolicy(false);
                                  return remoteRepo.getId().equals(testingRepo.getId()) &&
                                          !snapshotsPolicy.isEnabled() &&
                                          snapshotsPolicy.getUpdatePolicy().equals(testSnapshotPolicy.getUpdatePolicy()) &&
                                          snapshotsPolicy.getChecksumPolicy().equals(testSnapshotPolicy.getChecksumPolicy()) &&
                                          releasesPolicy.isEnabled() &&
                                          releasesPolicy.getUpdatePolicy().equals(testReleasesPolicy.getUpdatePolicy()) &&
                                          releasesPolicy.getChecksumPolicy().equals(testReleasesPolicy.getChecksumPolicy());
                              })
    );
}
 

@Override
public void addRepository(final Repository repository, boolean replace) throws InvalidRepositoryException
{
   if (session.isIgnoreArtifactDescriptorRepositories())
   {
      return;
   }

   if (!repositoryIds.add(repository.getId()))
   {
      if (!replace)
      {
         return;
      }

      removeMatchingRepository(repository.getId());
   }
   repositories.add(new RemoteRepository.Builder(repository.getId(), repository.getName(), repository.getUrl())
            .build());
}
 

/**
 * Used by the Maven Plugin.
 * @param repositorySystem Maven repository system
 * @param remoteRepositories remote artifact repositories
 * @param session repository system session
 */
public AetherStubDownloader(RepositorySystem repositorySystem,
		List<RemoteRepository> remoteRepositories, RepositorySystemSession session,
		Settings settings) {
	this.deleteStubsAfterTest = true;
	this.remoteRepos = remoteRepositories;
	this.settings = settings;
	this.repositorySystem = repositorySystem;
	this.session = session;
	if (remoteReposMissing()) {
		log.error(
				"Remote repositories for stubs are not specified and work offline flag wasn't passed");
	}
	this.workOffline = false;
	registerShutdownHook();
}
 

@Test
public void localResolutionSucceedsIfCached() throws Exception {
	String coordinates = "org.springframework.cloud.task.app:timestamp-task:jar:1.0.0.BUILD-SNAPSHOT";
	MavenProperties properties1 = new MavenProperties();
	String tempLocalRepo = System.getProperty("java.io.tmpdir") + File.separator + ".m2-test3";
	new File(tempLocalRepo).deleteOnExit();
	properties1.setLocalRepository(tempLocalRepo);
	Map<String, MavenProperties.RemoteRepository> remoteRepositoryMap = new HashMap<>();
	remoteRepositoryMap.put("default",
			new MavenProperties.RemoteRepository("https://repo.spring.io/libs-snapshot-local"));
	properties1.setRemoteRepositories(remoteRepositoryMap);
	MavenResource resource = MavenResource.parse(coordinates, properties1);
	resource.getFile();

	// no remotes; should not fail anymore
	MavenProperties properties2 = new MavenProperties();
	properties2.setLocalRepository(tempLocalRepo);
	properties2.setOffline(true);
	resource = new MavenResource.Builder(properties2)
			.artifactId("timestamp-task")
			.groupId("org.springframework.cloud.task.app")
			.version("1.0.0.BUILD-SNAPSHOT")
			.build();
	resource.getFile();
}
 

MavenArtifactResolver(List<Repository> repositories) {
    this.repositorySystem = createRepositorySystem();
    this.remoteRepositories = new LinkedList<>();
    repositories.forEach(r -> {
        RemoteRepository repository = new RemoteRepository
                .Builder(r.getId(), "default", r.getUrl())
                .build();
        remoteRepositories.add(repository);
    });
}
 

/** Adds a user-specified repository to the list. */
public void addUserRepository(String url) {
  Repository repository = new Repository();
  repository.setUrl(url);
  repository.setId("user-defined repository");
  repository.setName("default");
  addRepository(repository);
  this.aether.addRemoteRepository(
      new RemoteRepository.Builder("user-defined repository", "default", url).build());
}
 

public List<com.baidu.formula.launcher.model.Dependency> getArtifactsDependencies(
        MavenProject project, String scope)
        throws DependencyCollectionException, DependencyResolutionException {
    DefaultArtifact pomArtifact = new DefaultArtifact(project.getId());

    List<RemoteRepository> remoteRepos = project.getRemoteProjectRepositories();
    List<Dependency> ret = new ArrayList<Dependency>();

    Dependency dependency = new Dependency(pomArtifact, scope);

    CollectRequest collectRequest = new CollectRequest();
    collectRequest.setRoot(dependency);
    collectRequest.setRepositories(remoteRepos);

    DependencyNode node = repositorySystem.collectDependencies(session, collectRequest).getRoot();
    DependencyRequest projectDependencyRequest = new DependencyRequest(node, null);

    repositorySystem.resolveDependencies(session, projectDependencyRequest);

    PreorderNodeListGenerator nlg = new PreorderNodeListGenerator();
    node.accept(nlg);

    ret.addAll(nlg.getDependencies(true));
    return ret.stream().map(d -> {
        com.baidu.formula.launcher.model.Dependency dep = new com.baidu.formula.launcher.model.Dependency();
        dep.setArtifactId(d.getArtifact().getArtifactId());
        dep.setGroupId(d.getArtifact().getGroupId());
        dep.setVersion(d.getArtifact().getVersion());
        return dep;
    }).collect(Collectors.toList());
}
 

static RemoteRepository createRemoteRepository(String id, String url, boolean snapshot) {
	Builder repositoryBuilder = new Builder(id, "default", url);
	if (snapshot) {
		repositoryBuilder.setSnapshotPolicy(repositoryPolicy);
	}
	else {
		repositoryBuilder.setReleasePolicy(repositoryPolicy);
	}
	return repositoryBuilder.build();
}
 

private Stream<Dependency> getManagedDependencies(String groupId, String artifactId, String version,
		List<RemoteRepository> repositories) {
	String key = groupId + ":" + artifactId + ":" + version;
	List<org.eclipse.aether.graph.Dependency> managedDependencies = DependencyResolver.managedDependencies
			.computeIfAbsent(key,
					(coords) -> resolveManagedDependencies(groupId, artifactId, version, repositories));
	return managedDependencies.stream();
}
 

private List<Dependency> obtainBomDependencies(final String urlLocation) {
    final Artifact artifact = downloadAndInstallArtifact(urlLocation).getArtifact();

    final Dependency dependency = new Dependency(artifact, JavaScopes.RUNTIME);

    final List<RemoteRepository> remoteRepositories = project.getRepositories().stream()
        .map(r -> new RemoteRepository.Builder(r.getId(), r.getLayout(), r.getUrl()).build())
        .collect(Collectors.toList());

    CollectResult result;
    try {
        final ArtifactDescriptorRequest descriptorRequest = new ArtifactDescriptorRequest(artifact, remoteRepositories, null);
        final ArtifactDescriptorResult descriptor = repository.readArtifactDescriptor(session, descriptorRequest);

        final List<Dependency> dependencies = Stream.concat(
            descriptor.getDependencies().stream(),
            descriptor.getManagedDependencies().stream())
            .collect(Collectors.toList());

        final DefaultRepositorySystemSession sessionToUse = new DefaultRepositorySystemSession(session);
        sessionToUse.setDependencyGraphTransformer(new NoopDependencyGraphTransformer());

        final CollectRequest request = new CollectRequest(dependency, dependencies, remoteRepositories);
        result = repository.collectDependencies(sessionToUse, request);
    } catch (final DependencyCollectionException | ArtifactDescriptorException e) {
        throw new IllegalStateException("Unabele to obtain BOM dependencies for: " + urlLocation, e);
    }

    final DependencyNode root = result.getRoot();

    final PostorderNodeListGenerator visitor = new PostorderNodeListGenerator();
    root.accept(visitor);

    return visitor.getDependencies(true);
}
 

public RuntimeParams(List<AbstractBoosterConfig> boosterConfigs, Properties boostProperties, ExecutionEnvironment env, MavenProject project,
        Log log, RepositorySystem repoSystem, RepositorySystemSession repoSession,
        List<RemoteRepository> remoteRepos, Plugin mavenDepPlugin) {
    this.log = log;
    this.boosterConfigs = boosterConfigs;
    this.boostProperties = boostProperties;
    this.env = env;
    this.project = project;
    this.projectBuildDir = project.getBuild().getDirectory();
    this.repoSystem = repoSystem;
    this.repoSession = repoSession;
    this.remoteRepos = remoteRepos;
    this.mavenDepPlugin = mavenDepPlugin;
}
 

@Inject
public ArtifactResolver(RepositorySystem repoSystem, RepositorySystemSession repoSession,
    @Named("projectRepositories") List<RemoteRepository> remoteProjectRepos, Logger log) {
  this.repoSession = repoSession;
  this.cache = CacheBuilder.newBuilder()
      .build(new ArtifactCacheLoader(repoSystem, repoSession, remoteProjectRepos, log));
}
 

public static List<RemoteRepository> toRepos(List<ArtifactRepository> repos) {
  if (repos == null) {
    return null;
  }

  List<RemoteRepository> results = new ArrayList<RemoteRepository>(repos.size());
  for (ArtifactRepository repo : repos) {
    results.add(toRepo(repo));
  }
  return results;
}
 

@Override
public RepositoryConnector newInstance(RepositorySystemSession session, RemoteRepository repository) throws NoRepositoryConnectorException {
    // Throwing NoRepositoryConnectorException is ineffective because DefaultRemoteRepositoryManager will just skip to WagonRepositoryConnectorFactory.
    // (No apparent way to suppress WRCF from the Plexus container; using "wagon" as the role hint does not work.)
    // Could also return a no-op RepositoryConnector which would perform no downloads.
    // But we anyway want to ensure that related code is consistently setting the offline flag on all Maven structures that require it.
    // Throwing NoRepositoryConnectorException is ineffective because DefaultRemoteRepositoryManager will just skip to WagonRepositoryConnectorFactory.
    // (No apparent way to suppress WRCF from the Plexus container; using "wagon" as the role hint does not work.)
    // Could also return a no-op RepositoryConnector which would perform no downloads.
    // But we anyway want to ensure that related code is consistently setting the offline flag on all Maven structures that require it.
    throw new AssertionError();
}
 

/**
 * Deploys the given artifacts to the configured remote Maven repositories.
 *
 * @param artifacts the artifacts to deploy.
 * @return the artifacts that have been deployed successfully.
 * @throws DeploymentException if anything goes wrong during the deployment process.
 */
public Collection<Artifact> deployArtifacts(Collection<Artifact> artifacts) throws DeploymentException {
  Collection<Artifact> result = deploy(artifacts, this.metadata.getDeploymentRepository());
  for (RemoteRepository repo : this.additonalDeploymentRepositories) {
    deploy(artifacts, repo);
  }
  return result;
}
 

@Test
public void testProxy() throws Exception {
    RepositorySystem system = Util.newRepositorySystem();
    MavenConfig config = new MavenConfig();
    InputStream stream = MvnSettingsTestCase.class.getClassLoader().
            getResourceAsStream("settings_cli_test_proxy.xml");
    File tmp = File.createTempFile("cli_mvn_test", null);
    tmp.deleteOnExit();
    Files.copy(stream, tmp.toPath(), StandardCopyOption.REPLACE_EXISTING);
    config.setSettings(tmp.toPath());
    MavenMvnSettings settings = new MavenMvnSettings(config, system, null);
    ProxySelector proxy = settings.getSession().getProxySelector();
    assertEquals(6, settings.getRepositories().size());
    for (RemoteRepository remote : settings.getRepositories()) {
        if (remote.getId().equals("repo1")) {
            assertNull(proxy.getProxy(remote));
            assertNull(remote.getProxy());
        }
        if (remote.getId().equals("repo2")) {
            assertNull(proxy.getProxy(remote));
            assertNull(remote.getProxy());
        }
        if (remote.getId().equals("repo3")) {
            Proxy p = proxy.getProxy(remote);
            assertEquals("proxy1", p.getHost());
            assertNotNull(remote.getProxy());
        }
    }
}
 

VersionSubstitutingModelResolver(
    RepositorySystemSession session,
    RequestTrace trace,
    RepositorySystem resolver,
    RemoteRepositoryManager remoteRepositoryManager,
    List<RemoteRepository> repositories,
    Map<String, String> versionSubstitution) {
  super(session, trace, resolver, remoteRepositoryManager, repositories, null, null);
  this.session = session;
  this.trace = trace;
  this.resolver = resolver;
  this.remoteRepositoryManager = remoteRepositoryManager;
  this.repositories = ImmutableList.copyOf(repositories);
  this.versionSubstitution = ImmutableMap.copyOf(versionSubstitution);
}
 

private DependencyNode resolveCompileTimeDependencies(
    List<DependencyNode> dependencyNodes, DefaultRepositorySystemSession session)
    throws DependencyResolutionException {

  ImmutableList.Builder<Dependency> dependenciesBuilder = ImmutableList.builder();
  for (DependencyNode dependencyNode : dependencyNodes) {
    Dependency dependency = dependencyNode.getDependency();
    if (dependency == null) {
      // Root DependencyNode has null dependency field.
      dependenciesBuilder.add(new Dependency(dependencyNode.getArtifact(), "compile"));
    } else {
      // The dependency field carries exclusions
      dependenciesBuilder.add(dependency.setScope("compile"));
    }
  }
  ImmutableList<Dependency> dependencyList = dependenciesBuilder.build();
          
  if (localRepository != null) {
    LocalRepository local = new LocalRepository(localRepository.toAbsolutePath().toString());
    session.setLocalRepositoryManager(system.newLocalRepositoryManager(session, local));
  }

  CollectRequest collectRequest = new CollectRequest();
  if (dependencyList.size() == 1) {
    // With setRoot, the result includes dependencies with `optional:true` or `provided`
    collectRequest.setRoot(dependencyList.get(0));
  } else {
    collectRequest.setDependencies(dependencyList);
  }
  for (RemoteRepository repository : repositories) {
    collectRequest.addRepository(repository);
  }
  DependencyRequest dependencyRequest = new DependencyRequest();
  dependencyRequest.setCollectRequest(collectRequest);

  // resolveDependencies equals to calling both collectDependencies (build dependency tree) and
  // resolveArtifacts (download JAR files).
  DependencyResult dependencyResult = system.resolveDependencies(session, dependencyRequest);
  return dependencyResult.getRoot();
}