001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.eclipse.aether.internal.impl;
020
021import javax.inject.Inject;
022import javax.inject.Named;
023import javax.inject.Singleton;
024
025import java.io.File;
026import java.io.IOException;
027import java.util.ArrayList;
028import java.util.Collection;
029import java.util.Collections;
030import java.util.Iterator;
031import java.util.List;
032import java.util.Map;
033import java.util.concurrent.atomic.AtomicBoolean;
034
035import org.eclipse.aether.RepositoryEvent;
036import org.eclipse.aether.RepositoryEvent.EventType;
037import org.eclipse.aether.RepositorySystemSession;
038import org.eclipse.aether.RequestTrace;
039import org.eclipse.aether.SyncContext;
040import org.eclipse.aether.artifact.Artifact;
041import org.eclipse.aether.artifact.ArtifactProperties;
042import org.eclipse.aether.impl.ArtifactResolver;
043import org.eclipse.aether.impl.OfflineController;
044import org.eclipse.aether.impl.RemoteRepositoryFilterManager;
045import org.eclipse.aether.impl.RemoteRepositoryManager;
046import org.eclipse.aether.impl.RepositoryConnectorProvider;
047import org.eclipse.aether.impl.RepositoryEventDispatcher;
048import org.eclipse.aether.impl.UpdateCheck;
049import org.eclipse.aether.impl.UpdateCheckManager;
050import org.eclipse.aether.impl.VersionResolver;
051import org.eclipse.aether.repository.ArtifactRepository;
052import org.eclipse.aether.repository.LocalArtifactRegistration;
053import org.eclipse.aether.repository.LocalArtifactRequest;
054import org.eclipse.aether.repository.LocalArtifactResult;
055import org.eclipse.aether.repository.LocalRepository;
056import org.eclipse.aether.repository.LocalRepositoryManager;
057import org.eclipse.aether.repository.RemoteRepository;
058import org.eclipse.aether.repository.RepositoryPolicy;
059import org.eclipse.aether.repository.WorkspaceReader;
060import org.eclipse.aether.resolution.ArtifactRequest;
061import org.eclipse.aether.resolution.ArtifactResolutionException;
062import org.eclipse.aether.resolution.ArtifactResult;
063import org.eclipse.aether.resolution.ResolutionErrorPolicy;
064import org.eclipse.aether.resolution.VersionRequest;
065import org.eclipse.aether.resolution.VersionResolutionException;
066import org.eclipse.aether.resolution.VersionResult;
067import org.eclipse.aether.spi.connector.ArtifactDownload;
068import org.eclipse.aether.spi.connector.RepositoryConnector;
069import org.eclipse.aether.spi.connector.filter.RemoteRepositoryFilter;
070import org.eclipse.aether.spi.io.FileProcessor;
071import org.eclipse.aether.spi.locator.Service;
072import org.eclipse.aether.spi.locator.ServiceLocator;
073import org.eclipse.aether.spi.resolution.ArtifactResolverPostProcessor;
074import org.eclipse.aether.spi.synccontext.SyncContextFactory;
075import org.eclipse.aether.transfer.ArtifactFilteredOutException;
076import org.eclipse.aether.transfer.ArtifactNotFoundException;
077import org.eclipse.aether.transfer.ArtifactTransferException;
078import org.eclipse.aether.transfer.NoRepositoryConnectorException;
079import org.eclipse.aether.transfer.RepositoryOfflineException;
080import org.eclipse.aether.util.ConfigUtils;
081import org.slf4j.Logger;
082import org.slf4j.LoggerFactory;
083
084import static java.util.Objects.requireNonNull;
085
086/**
087 *
088 */
089@Singleton
090@Named
091public class DefaultArtifactResolver implements ArtifactResolver, Service {
092
093    /**
094     * Configuration to enable "snapshot normalization", downloaded snapshots from remote with timestamped file names
095     * will have file names converted back to baseVersion. Default: {@code true}.
096     */
097    private static final String CONFIG_PROP_SNAPSHOT_NORMALIZATION = "aether.artifactResolver.snapshotNormalization";
098
099    /**
100     * Configuration to enable "interoperability" with Simple LRM, but this breaks RRF feature, hence this configuration
101     * is IGNORED when RRF is used, and is warmly recommended to leave it disabled even if no RRF is being used.
102     * Default: {@code false}.
103     */
104    private static final String CONFIG_PROP_SIMPLE_LRM_INTEROP = "aether.artifactResolver.simpleLrmInterop";
105
106    private static final Logger LOGGER = LoggerFactory.getLogger(DefaultArtifactResolver.class);
107
108    private FileProcessor fileProcessor;
109
110    private RepositoryEventDispatcher repositoryEventDispatcher;
111
112    private VersionResolver versionResolver;
113
114    private UpdateCheckManager updateCheckManager;
115
116    private RepositoryConnectorProvider repositoryConnectorProvider;
117
118    private RemoteRepositoryManager remoteRepositoryManager;
119
120    private SyncContextFactory syncContextFactory;
121
122    private OfflineController offlineController;
123
124    private Map<String, ArtifactResolverPostProcessor> artifactResolverPostProcessors;
125
126    private RemoteRepositoryFilterManager remoteRepositoryFilterManager;
127
128    public DefaultArtifactResolver() {
129        // enables default constructor
130    }
131
132    @SuppressWarnings("checkstyle:parameternumber")
133    @Inject
134    DefaultArtifactResolver(
135            FileProcessor fileProcessor,
136            RepositoryEventDispatcher repositoryEventDispatcher,
137            VersionResolver versionResolver,
138            UpdateCheckManager updateCheckManager,
139            RepositoryConnectorProvider repositoryConnectorProvider,
140            RemoteRepositoryManager remoteRepositoryManager,
141            SyncContextFactory syncContextFactory,
142            OfflineController offlineController,
143            Map<String, ArtifactResolverPostProcessor> artifactResolverPostProcessors,
144            RemoteRepositoryFilterManager remoteRepositoryFilterManager) {
145        setFileProcessor(fileProcessor);
146        setRepositoryEventDispatcher(repositoryEventDispatcher);
147        setVersionResolver(versionResolver);
148        setUpdateCheckManager(updateCheckManager);
149        setRepositoryConnectorProvider(repositoryConnectorProvider);
150        setRemoteRepositoryManager(remoteRepositoryManager);
151        setSyncContextFactory(syncContextFactory);
152        setOfflineController(offlineController);
153        setArtifactResolverPostProcessors(artifactResolverPostProcessors);
154        setRemoteRepositoryFilterManager(remoteRepositoryFilterManager);
155    }
156
157    public void initService(ServiceLocator locator) {
158        setFileProcessor(locator.getService(FileProcessor.class));
159        setRepositoryEventDispatcher(locator.getService(RepositoryEventDispatcher.class));
160        setVersionResolver(locator.getService(VersionResolver.class));
161        setUpdateCheckManager(locator.getService(UpdateCheckManager.class));
162        setRepositoryConnectorProvider(locator.getService(RepositoryConnectorProvider.class));
163        setRemoteRepositoryManager(locator.getService(RemoteRepositoryManager.class));
164        setSyncContextFactory(locator.getService(SyncContextFactory.class));
165        setOfflineController(locator.getService(OfflineController.class));
166        setArtifactResolverPostProcessors(Collections.emptyMap());
167        setRemoteRepositoryFilterManager(locator.getService(RemoteRepositoryFilterManager.class));
168    }
169
170    /**
171     * @deprecated not used any more since MRESOLVER-36 move to slf4j, added back in MRESOLVER-64 for compatibility
172     */
173    @Deprecated
174    public DefaultArtifactResolver setLoggerFactory(org.eclipse.aether.spi.log.LoggerFactory loggerFactory) {
175        // this.logger = NullLoggerFactory.getSafeLogger( loggerFactory, getClass() );
176        return this;
177    }
178
179    public DefaultArtifactResolver setFileProcessor(FileProcessor fileProcessor) {
180        this.fileProcessor = requireNonNull(fileProcessor, "file processor cannot be null");
181        return this;
182    }
183
184    public DefaultArtifactResolver setRepositoryEventDispatcher(RepositoryEventDispatcher repositoryEventDispatcher) {
185        this.repositoryEventDispatcher =
186                requireNonNull(repositoryEventDispatcher, "repository event dispatcher cannot be null");
187        return this;
188    }
189
190    public DefaultArtifactResolver setVersionResolver(VersionResolver versionResolver) {
191        this.versionResolver = requireNonNull(versionResolver, "version resolver cannot be null");
192        return this;
193    }
194
195    public DefaultArtifactResolver setUpdateCheckManager(UpdateCheckManager updateCheckManager) {
196        this.updateCheckManager = requireNonNull(updateCheckManager, "update check manager cannot be null");
197        return this;
198    }
199
200    public DefaultArtifactResolver setRepositoryConnectorProvider(
201            RepositoryConnectorProvider repositoryConnectorProvider) {
202        this.repositoryConnectorProvider =
203                requireNonNull(repositoryConnectorProvider, "repository connector provider cannot be null");
204        return this;
205    }
206
207    public DefaultArtifactResolver setRemoteRepositoryManager(RemoteRepositoryManager remoteRepositoryManager) {
208        this.remoteRepositoryManager =
209                requireNonNull(remoteRepositoryManager, "remote repository provider cannot be null");
210        return this;
211    }
212
213    public DefaultArtifactResolver setSyncContextFactory(SyncContextFactory syncContextFactory) {
214        this.syncContextFactory = requireNonNull(syncContextFactory, "sync context factory cannot be null");
215        return this;
216    }
217
218    public DefaultArtifactResolver setOfflineController(OfflineController offlineController) {
219        this.offlineController = requireNonNull(offlineController, "offline controller cannot be null");
220        return this;
221    }
222
223    public DefaultArtifactResolver setArtifactResolverPostProcessors(
224            Map<String, ArtifactResolverPostProcessor> artifactResolverPostProcessors) {
225        this.artifactResolverPostProcessors =
226                requireNonNull(artifactResolverPostProcessors, "artifact resolver post-processors cannot be null");
227        return this;
228    }
229
230    public DefaultArtifactResolver setRemoteRepositoryFilterManager(
231            RemoteRepositoryFilterManager remoteRepositoryFilterManager) {
232        this.remoteRepositoryFilterManager =
233                requireNonNull(remoteRepositoryFilterManager, "remote repository filter manager cannot be null");
234        return this;
235    }
236
237    public ArtifactResult resolveArtifact(RepositorySystemSession session, ArtifactRequest request)
238            throws ArtifactResolutionException {
239        requireNonNull(session, "session cannot be null");
240        requireNonNull(request, "request cannot be null");
241
242        return resolveArtifacts(session, Collections.singleton(request)).get(0);
243    }
244
245    public List<ArtifactResult> resolveArtifacts(
246            RepositorySystemSession session, Collection<? extends ArtifactRequest> requests)
247            throws ArtifactResolutionException {
248        requireNonNull(session, "session cannot be null");
249        requireNonNull(requests, "requests cannot be null");
250        try (SyncContext exclusive = syncContextFactory.newInstance(session, false)) {
251            Collection<Artifact> artifacts = new ArrayList<>(requests.size());
252            for (ArtifactRequest request : requests) {
253                if (request.getArtifact().getProperty(ArtifactProperties.LOCAL_PATH, null) != null) {
254                    continue;
255                }
256                artifacts.add(request.getArtifact());
257            }
258
259            return resolve(exclusive, artifacts, session, requests);
260        }
261    }
262
263    @SuppressWarnings("checkstyle:methodlength")
264    private List<ArtifactResult> resolve(
265            SyncContext syncContext,
266            Collection<Artifact> subjects,
267            RepositorySystemSession session,
268            Collection<? extends ArtifactRequest> requests)
269            throws ArtifactResolutionException {
270        try {
271            syncContext.acquire(subjects, null);
272
273            boolean failures = false;
274            final List<ArtifactResult> results = new ArrayList<>(requests.size());
275            final boolean simpleLrmInterop = ConfigUtils.getBoolean(session, false, CONFIG_PROP_SIMPLE_LRM_INTEROP);
276            final LocalRepositoryManager lrm = session.getLocalRepositoryManager();
277            final WorkspaceReader workspace = session.getWorkspaceReader();
278            final List<ResolutionGroup> groups = new ArrayList<>();
279            // filter != null: means "filtering applied", if null no filtering applied (behave as before)
280            final RemoteRepositoryFilter filter = remoteRepositoryFilterManager.getRemoteRepositoryFilter(session);
281
282            for (ArtifactRequest request : requests) {
283                RequestTrace trace = RequestTrace.newChild(request.getTrace(), request);
284
285                ArtifactResult result = new ArtifactResult(request);
286                results.add(result);
287
288                Artifact artifact = request.getArtifact();
289
290                artifactResolving(session, trace, artifact);
291
292                String localPath = artifact.getProperty(ArtifactProperties.LOCAL_PATH, null);
293                if (localPath != null) {
294                    // unhosted artifact, just validate file
295                    File file = new File(localPath);
296                    if (!file.isFile()) {
297                        failures = true;
298                        result.addException(new ArtifactNotFoundException(artifact, null));
299                    } else {
300                        artifact = artifact.setFile(file);
301                        result.setArtifact(artifact);
302                        artifactResolved(session, trace, artifact, null, result.getExceptions());
303                    }
304                    continue;
305                }
306
307                List<RemoteRepository> remoteRepositories = request.getRepositories();
308                List<RemoteRepository> filteredRemoteRepositories = new ArrayList<>(remoteRepositories);
309                if (filter != null) {
310                    for (RemoteRepository repository : remoteRepositories) {
311                        RemoteRepositoryFilter.Result filterResult = filter.acceptArtifact(repository, artifact);
312                        if (!filterResult.isAccepted()) {
313                            result.addException(
314                                    new ArtifactFilteredOutException(artifact, repository, filterResult.reasoning()));
315                            filteredRemoteRepositories.remove(repository);
316                        }
317                    }
318                }
319
320                VersionResult versionResult;
321                try {
322                    VersionRequest versionRequest =
323                            new VersionRequest(artifact, filteredRemoteRepositories, request.getRequestContext());
324                    versionRequest.setTrace(trace);
325                    versionResult = versionResolver.resolveVersion(session, versionRequest);
326                } catch (VersionResolutionException e) {
327                    result.addException(e);
328                    continue;
329                }
330
331                artifact = artifact.setVersion(versionResult.getVersion());
332
333                if (versionResult.getRepository() != null) {
334                    if (versionResult.getRepository() instanceof RemoteRepository) {
335                        filteredRemoteRepositories =
336                                Collections.singletonList((RemoteRepository) versionResult.getRepository());
337                    } else {
338                        filteredRemoteRepositories = Collections.emptyList();
339                    }
340                }
341
342                if (workspace != null) {
343                    File file = workspace.findArtifact(artifact);
344                    if (file != null) {
345                        artifact = artifact.setFile(file);
346                        result.setArtifact(artifact);
347                        result.setRepository(workspace.getRepository());
348                        artifactResolved(session, trace, artifact, result.getRepository(), null);
349                        continue;
350                    }
351                }
352
353                LocalArtifactResult local = lrm.find(
354                        session,
355                        new LocalArtifactRequest(artifact, filteredRemoteRepositories, request.getRequestContext()));
356                result.setLocalArtifactResult(local);
357                boolean found = (filter != null && local.isAvailable()) || isLocallyInstalled(local, versionResult);
358                // with filtering it is availability that drives logic
359                // without filtering it is simply presence of file that drives the logic
360                // "interop" logic with simple LRM leads to RRF breakage: hence is ignored when filtering in effect
361                if (found) {
362                    if (local.getRepository() != null) {
363                        result.setRepository(local.getRepository());
364                    } else {
365                        result.setRepository(lrm.getRepository());
366                    }
367
368                    try {
369                        artifact = artifact.setFile(getFile(session, artifact, local.getFile()));
370                        result.setArtifact(artifact);
371                        artifactResolved(session, trace, artifact, result.getRepository(), null);
372                    } catch (ArtifactTransferException e) {
373                        result.addException(e);
374                    }
375                    if (filter == null && simpleLrmInterop && !local.isAvailable()) {
376                        /*
377                         * NOTE: Interop with simple local repository: An artifact installed by a simple local repo
378                         * manager will not show up in the repository tracking file of the enhanced local repository.
379                         * If however the maven-metadata-local.xml tells us the artifact was installed locally, we
380                         * sync the repository tracking file.
381                         */
382                        lrm.add(session, new LocalArtifactRegistration(artifact));
383                    }
384
385                    continue;
386                }
387
388                if (local.getFile() != null) {
389                    LOGGER.info(
390                            "Artifact {} is present in the local repository, but cached from a remote repository ID that is unavailable in current build context, verifying that is downloadable from {}",
391                            artifact,
392                            remoteRepositories);
393                }
394
395                LOGGER.debug("Resolving artifact {} from {}", artifact, remoteRepositories);
396                AtomicBoolean resolved = new AtomicBoolean(false);
397                Iterator<ResolutionGroup> groupIt = groups.iterator();
398                for (RemoteRepository repo : filteredRemoteRepositories) {
399                    if (!repo.getPolicy(artifact.isSnapshot()).isEnabled()) {
400                        continue;
401                    }
402
403                    try {
404                        Utils.checkOffline(session, offlineController, repo);
405                    } catch (RepositoryOfflineException e) {
406                        Exception exception = new ArtifactNotFoundException(
407                                artifact,
408                                repo,
409                                "Cannot access " + repo.getId() + " ("
410                                        + repo.getUrl() + ") in offline mode and the artifact " + artifact
411                                        + " has not been downloaded from it before.",
412                                e);
413                        result.addException(exception);
414                        continue;
415                    }
416
417                    ResolutionGroup group = null;
418                    while (groupIt.hasNext()) {
419                        ResolutionGroup t = groupIt.next();
420                        if (t.matches(repo)) {
421                            group = t;
422                            break;
423                        }
424                    }
425                    if (group == null) {
426                        group = new ResolutionGroup(repo);
427                        groups.add(group);
428                        groupIt = Collections.emptyIterator();
429                    }
430                    group.items.add(new ResolutionItem(trace, artifact, resolved, result, local, repo));
431                }
432            }
433
434            for (ResolutionGroup group : groups) {
435                performDownloads(session, group);
436            }
437
438            for (ArtifactResolverPostProcessor artifactResolverPostProcessor :
439                    artifactResolverPostProcessors.values()) {
440                artifactResolverPostProcessor.postProcess(session, results);
441            }
442
443            for (ArtifactResult result : results) {
444                ArtifactRequest request = result.getRequest();
445
446                Artifact artifact = result.getArtifact();
447                if (artifact == null || artifact.getFile() == null) {
448                    failures = true;
449                    if (result.getExceptions().isEmpty()) {
450                        Exception exception = new ArtifactNotFoundException(request.getArtifact(), null);
451                        result.addException(exception);
452                    }
453                    RequestTrace trace = RequestTrace.newChild(request.getTrace(), request);
454                    artifactResolved(session, trace, request.getArtifact(), null, result.getExceptions());
455                }
456            }
457
458            if (failures) {
459                throw new ArtifactResolutionException(results);
460            }
461
462            return results;
463        } finally {
464            syncContext.close();
465        }
466    }
467
468    private boolean isLocallyInstalled(LocalArtifactResult lar, VersionResult vr) {
469        if (lar.isAvailable()) {
470            return true;
471        }
472        if (lar.getFile() != null) {
473            if (vr.getRepository() instanceof LocalRepository) {
474                // resolution of (snapshot) version found locally installed artifact
475                return true;
476            } else if (vr.getRepository() == null
477                    && lar.getRequest().getRepositories().isEmpty()) {
478                // resolution of version range found locally installed artifact
479                return true;
480            }
481        }
482        return false;
483    }
484
485    private File getFile(RepositorySystemSession session, Artifact artifact, File file)
486            throws ArtifactTransferException {
487        if (artifact.isSnapshot()
488                && !artifact.getVersion().equals(artifact.getBaseVersion())
489                && ConfigUtils.getBoolean(session, true, CONFIG_PROP_SNAPSHOT_NORMALIZATION)) {
490            String name = file.getName().replace(artifact.getVersion(), artifact.getBaseVersion());
491            File dst = new File(file.getParent(), name);
492
493            boolean copy = dst.length() != file.length() || dst.lastModified() != file.lastModified();
494            if (copy) {
495                try {
496                    fileProcessor.copy(file, dst);
497                    dst.setLastModified(file.lastModified());
498                } catch (IOException e) {
499                    throw new ArtifactTransferException(artifact, null, e);
500                }
501            }
502
503            file = dst;
504        }
505
506        return file;
507    }
508
509    private void performDownloads(RepositorySystemSession session, ResolutionGroup group) {
510        List<ArtifactDownload> downloads = gatherDownloads(session, group);
511        if (downloads.isEmpty()) {
512            return;
513        }
514
515        for (ArtifactDownload download : downloads) {
516            artifactDownloading(session, download.getTrace(), download.getArtifact(), group.repository);
517        }
518
519        try {
520            try (RepositoryConnector connector =
521                    repositoryConnectorProvider.newRepositoryConnector(session, group.repository)) {
522                connector.get(downloads, null);
523            }
524        } catch (NoRepositoryConnectorException e) {
525            for (ArtifactDownload download : downloads) {
526                download.setException(new ArtifactTransferException(download.getArtifact(), group.repository, e));
527            }
528        }
529
530        evaluateDownloads(session, group);
531    }
532
533    private List<ArtifactDownload> gatherDownloads(RepositorySystemSession session, ResolutionGroup group) {
534        LocalRepositoryManager lrm = session.getLocalRepositoryManager();
535        List<ArtifactDownload> downloads = new ArrayList<>();
536
537        for (ResolutionItem item : group.items) {
538            Artifact artifact = item.artifact;
539
540            if (item.resolved.get()) {
541                // resolved in previous resolution group
542                continue;
543            }
544
545            ArtifactDownload download = new ArtifactDownload();
546            download.setArtifact(artifact);
547            download.setRequestContext(item.request.getRequestContext());
548            download.setListener(SafeTransferListener.wrap(session));
549            download.setTrace(item.trace);
550            if (item.local.getFile() != null) {
551                download.setFile(item.local.getFile());
552                download.setExistenceCheck(true);
553            } else {
554                String path =
555                        lrm.getPathForRemoteArtifact(artifact, group.repository, item.request.getRequestContext());
556                download.setFile(new File(lrm.getRepository().getBasedir(), path));
557            }
558
559            boolean snapshot = artifact.isSnapshot();
560            RepositoryPolicy policy = remoteRepositoryManager.getPolicy(session, group.repository, !snapshot, snapshot);
561
562            int errorPolicy = Utils.getPolicy(session, artifact, group.repository);
563            if ((errorPolicy & ResolutionErrorPolicy.CACHE_ALL) != 0) {
564                UpdateCheck<Artifact, ArtifactTransferException> check = new UpdateCheck<>();
565                check.setItem(artifact);
566                check.setFile(download.getFile());
567                check.setFileValid(false);
568                check.setRepository(group.repository);
569                check.setPolicy(policy.getUpdatePolicy());
570                item.updateCheck = check;
571                updateCheckManager.checkArtifact(session, check);
572                if (!check.isRequired()) {
573                    item.result.addException(check.getException());
574                    continue;
575                }
576            }
577
578            download.setChecksumPolicy(policy.getChecksumPolicy());
579            download.setRepositories(item.repository.getMirroredRepositories());
580            downloads.add(download);
581            item.download = download;
582        }
583
584        return downloads;
585    }
586
587    private void evaluateDownloads(RepositorySystemSession session, ResolutionGroup group) {
588        LocalRepositoryManager lrm = session.getLocalRepositoryManager();
589
590        for (ResolutionItem item : group.items) {
591            ArtifactDownload download = item.download;
592            if (download == null) {
593                continue;
594            }
595
596            Artifact artifact = download.getArtifact();
597            if (download.getException() == null) {
598                item.resolved.set(true);
599                item.result.setRepository(group.repository);
600                try {
601                    artifact = artifact.setFile(getFile(session, artifact, download.getFile()));
602                    item.result.setArtifact(artifact);
603
604                    lrm.add(
605                            session,
606                            new LocalArtifactRegistration(artifact, group.repository, download.getSupportedContexts()));
607                } catch (ArtifactTransferException e) {
608                    download.setException(e);
609                    item.result.addException(e);
610                }
611            } else {
612                item.result.addException(download.getException());
613            }
614
615            /*
616             * NOTE: Touch after registration with local repo to ensure concurrent resolution is not rejected with
617             * "already updated" via session data when actual update to local repo is still pending.
618             */
619            if (item.updateCheck != null) {
620                item.updateCheck.setException(download.getException());
621                updateCheckManager.touchArtifact(session, item.updateCheck);
622            }
623
624            artifactDownloaded(session, download.getTrace(), artifact, group.repository, download.getException());
625            if (download.getException() == null) {
626                artifactResolved(session, download.getTrace(), artifact, group.repository, null);
627            }
628        }
629    }
630
631    private void artifactResolving(RepositorySystemSession session, RequestTrace trace, Artifact artifact) {
632        RepositoryEvent.Builder event = new RepositoryEvent.Builder(session, EventType.ARTIFACT_RESOLVING);
633        event.setTrace(trace);
634        event.setArtifact(artifact);
635
636        repositoryEventDispatcher.dispatch(event.build());
637    }
638
639    private void artifactResolved(
640            RepositorySystemSession session,
641            RequestTrace trace,
642            Artifact artifact,
643            ArtifactRepository repository,
644            List<Exception> exceptions) {
645        RepositoryEvent.Builder event = new RepositoryEvent.Builder(session, EventType.ARTIFACT_RESOLVED);
646        event.setTrace(trace);
647        event.setArtifact(artifact);
648        event.setRepository(repository);
649        event.setExceptions(exceptions);
650        if (artifact != null) {
651            event.setFile(artifact.getFile());
652        }
653
654        repositoryEventDispatcher.dispatch(event.build());
655    }
656
657    private void artifactDownloading(
658            RepositorySystemSession session, RequestTrace trace, Artifact artifact, RemoteRepository repository) {
659        RepositoryEvent.Builder event = new RepositoryEvent.Builder(session, EventType.ARTIFACT_DOWNLOADING);
660        event.setTrace(trace);
661        event.setArtifact(artifact);
662        event.setRepository(repository);
663
664        repositoryEventDispatcher.dispatch(event.build());
665    }
666
667    private void artifactDownloaded(
668            RepositorySystemSession session,
669            RequestTrace trace,
670            Artifact artifact,
671            RemoteRepository repository,
672            Exception exception) {
673        RepositoryEvent.Builder event = new RepositoryEvent.Builder(session, EventType.ARTIFACT_DOWNLOADED);
674        event.setTrace(trace);
675        event.setArtifact(artifact);
676        event.setRepository(repository);
677        event.setException(exception);
678        if (artifact != null) {
679            event.setFile(artifact.getFile());
680        }
681
682        repositoryEventDispatcher.dispatch(event.build());
683    }
684
685    static class ResolutionGroup {
686
687        final RemoteRepository repository;
688
689        final List<ResolutionItem> items = new ArrayList<>();
690
691        ResolutionGroup(RemoteRepository repository) {
692            this.repository = repository;
693        }
694
695        boolean matches(RemoteRepository repo) {
696            return repository.getUrl().equals(repo.getUrl())
697                    && repository.getContentType().equals(repo.getContentType())
698                    && repository.isRepositoryManager() == repo.isRepositoryManager();
699        }
700    }
701
702    static class ResolutionItem {
703
704        final RequestTrace trace;
705
706        final ArtifactRequest request;
707
708        final ArtifactResult result;
709
710        final LocalArtifactResult local;
711
712        final RemoteRepository repository;
713
714        final Artifact artifact;
715
716        final AtomicBoolean resolved;
717
718        ArtifactDownload download;
719
720        UpdateCheck<Artifact, ArtifactTransferException> updateCheck;
721
722        ResolutionItem(
723                RequestTrace trace,
724                Artifact artifact,
725                AtomicBoolean resolved,
726                ArtifactResult result,
727                LocalArtifactResult local,
728                RemoteRepository repository) {
729            this.trace = trace;
730            this.artifact = artifact;
731            this.resolved = resolved;
732            this.result = result;
733            this.request = result.getRequest();
734            this.local = local;
735            this.repository = repository;
736        }
737    }
738}