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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.maven.project.artifact;
20  
21  import java.io.File;
22  import java.util.ArrayList;
23  import java.util.Arrays;
24  import java.util.Collection;
25  import java.util.Collections;
26  import java.util.HashMap;
27  import java.util.LinkedHashMap;
28  import java.util.LinkedHashSet;
29  import java.util.List;
30  import java.util.Map;
31  import java.util.Properties;
32  import java.util.Set;
33  
34  import org.apache.maven.RepositoryUtils;
35  import org.apache.maven.artifact.Artifact;
36  import org.apache.maven.artifact.ArtifactUtils;
37  import org.apache.maven.artifact.factory.ArtifactFactory;
38  import org.apache.maven.artifact.metadata.ArtifactMetadataRetrievalException;
39  import org.apache.maven.artifact.metadata.ArtifactMetadataSource;
40  import org.apache.maven.artifact.metadata.ResolutionGroup;
41  import org.apache.maven.artifact.repository.ArtifactRepository;
42  import org.apache.maven.artifact.repository.metadata.ArtifactRepositoryMetadata;
43  import org.apache.maven.artifact.repository.metadata.Metadata;
44  import org.apache.maven.artifact.repository.metadata.RepositoryMetadata;
45  import org.apache.maven.artifact.repository.metadata.RepositoryMetadataManager;
46  import org.apache.maven.artifact.repository.metadata.RepositoryMetadataResolutionException;
47  import org.apache.maven.artifact.resolver.ArtifactResolutionException;
48  import org.apache.maven.artifact.resolver.MultipleArtifactsNotFoundException;
49  import org.apache.maven.artifact.resolver.filter.AndArtifactFilter;
50  import org.apache.maven.artifact.resolver.filter.ArtifactFilter;
51  import org.apache.maven.artifact.resolver.filter.ExclusionArtifactFilter;
52  import org.apache.maven.artifact.versioning.ArtifactVersion;
53  import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
54  import org.apache.maven.artifact.versioning.InvalidVersionSpecificationException;
55  import org.apache.maven.artifact.versioning.VersionRange;
56  import org.apache.maven.execution.MavenSession;
57  import org.apache.maven.model.Dependency;
58  import org.apache.maven.model.DependencyManagement;
59  import org.apache.maven.model.DistributionManagement;
60  import org.apache.maven.model.Model;
61  import org.apache.maven.model.Relocation;
62  import org.apache.maven.model.building.ModelBuildingException;
63  import org.apache.maven.model.building.ModelBuildingRequest;
64  import org.apache.maven.model.building.ModelProblem;
65  import org.apache.maven.model.resolution.UnresolvableModelException;
66  import org.apache.maven.plugin.LegacySupport;
67  import org.apache.maven.project.DefaultProjectBuildingRequest;
68  import org.apache.maven.project.MavenProject;
69  import org.apache.maven.project.ProjectBuilder;
70  import org.apache.maven.project.ProjectBuildingException;
71  import org.apache.maven.project.ProjectBuildingRequest;
72  import org.apache.maven.properties.internal.EnvironmentUtils;
73  import org.apache.maven.properties.internal.SystemProperties;
74  import org.apache.maven.repository.internal.MavenWorkspaceReader;
75  import org.apache.maven.repository.legacy.metadata.DefaultMetadataResolutionRequest;
76  import org.apache.maven.repository.legacy.metadata.MetadataResolutionRequest;
77  import org.codehaus.plexus.PlexusContainer;
78  import org.codehaus.plexus.component.annotations.Component;
79  import org.codehaus.plexus.component.annotations.Requirement;
80  import org.codehaus.plexus.component.repository.exception.ComponentLookupException;
81  import org.codehaus.plexus.logging.Logger;
82  import org.eclipse.aether.RepositorySystemSession;
83  import org.eclipse.aether.repository.RepositoryPolicy;
84  import org.eclipse.aether.repository.WorkspaceReader;
85  import org.eclipse.aether.transfer.ArtifactNotFoundException;
86  
87  /**
88   * @author Jason van Zyl
89   */
90  @Component(role = ArtifactMetadataSource.class, hint = "maven")
91  public class MavenMetadataSource implements ArtifactMetadataSource {
92      @Requirement
93      private RepositoryMetadataManager repositoryMetadataManager;
94  
95      @Requirement
96      private ArtifactFactory repositorySystem;
97  
98      // TODO This prevents a cycle in the composition which shows us another problem we need to deal with.
99      // @Requirement
100     private ProjectBuilder projectBuilder;
101 
102     @Requirement
103     private PlexusContainer container;
104 
105     @Requirement
106     private Logger logger;
107 
108     @Requirement
109     private MavenMetadataCache cache;
110 
111     @Requirement
112     private LegacySupport legacySupport;
113 
114     private void injectSession(MetadataResolutionRequest request) {
115         RepositorySystemSession session = legacySupport.getRepositorySession();
116 
117         if (session != null) {
118             request.setOffline(session.isOffline());
119             request.setForceUpdate(RepositoryPolicy.UPDATE_POLICY_ALWAYS.equals(session.getUpdatePolicy()));
120         }
121     }
122 
123     public ResolutionGroup retrieve(
124             Artifact artifact, ArtifactRepository localRepository, List<ArtifactRepository> remoteRepositories)
125             throws ArtifactMetadataRetrievalException {
126         return retrieve(artifact, localRepository, remoteRepositories, false);
127     }
128 
129     public ResolutionGroup retrieve(
130             Artifact artifact,
131             ArtifactRepository localRepository,
132             List<ArtifactRepository> remoteRepositories,
133             boolean resolveManagedVersions)
134             throws ArtifactMetadataRetrievalException {
135         MetadataResolutionRequest request = new DefaultMetadataResolutionRequest();
136         injectSession(request);
137         request.setArtifact(artifact);
138         request.setLocalRepository(localRepository);
139         request.setRemoteRepositories(remoteRepositories);
140         request.setResolveManagedVersions(resolveManagedVersions);
141         return retrieve(request);
142     }
143 
144     public ResolutionGroup retrieve(MetadataResolutionRequest request) throws ArtifactMetadataRetrievalException {
145         Artifact artifact = request.getArtifact();
146 
147         //
148         // If we have a system scoped artifact then we do not want any searching in local or remote repositories
149         // and we want artifact resolution to only return the system scoped artifact itself.
150         //
151         if (artifact.getScope() != null && artifact.getScope().equals(Artifact.SCOPE_SYSTEM)) {
152             return new ResolutionGroup(null, null, null);
153         }
154 
155         ResolutionGroup cached = cache.get(
156                 artifact,
157                 request.isResolveManagedVersions(),
158                 request.getLocalRepository(),
159                 request.getRemoteRepositories());
160 
161         if (cached != null
162                 // if the POM has no file, we cached a missing artifact, only return the cached data if no update forced
163                 && (!request.isForceUpdate() || hasFile(cached.getPomArtifact()))) {
164             return cached;
165         }
166 
167         List<Dependency> dependencies;
168 
169         List<Dependency> managedDependencies = null;
170 
171         List<ArtifactRepository> pomRepositories = null;
172 
173         Artifact pomArtifact;
174 
175         Artifact relocatedArtifact = null;
176 
177         // TODO hack: don't rebuild model if it was already loaded during reactor resolution
178         final WorkspaceReader workspace = legacySupport.getRepositorySession().getWorkspaceReader();
179         Model model = null;
180         if (workspace instanceof MavenWorkspaceReader) {
181             model = ((MavenWorkspaceReader) workspace).findModel(RepositoryUtils.toArtifact(artifact));
182         }
183 
184         if (model != null) {
185             pomArtifact = artifact;
186             dependencies = model.getDependencies();
187             DependencyManagement dependencyManagement = model.getDependencyManagement();
188             managedDependencies = dependencyManagement == null ? null : dependencyManagement.getDependencies();
189             MavenSession session = legacySupport.getSession();
190             if (session != null) {
191                 MavenProject project = session.getProjectMap()
192                         .get(ArtifactUtils.key(artifact.getGroupId(), artifact.getArtifactId(), artifact.getVersion()));
193                 pomRepositories = project.getRemoteArtifactRepositories();
194             } else {
195                 pomRepositories = new ArrayList<>();
196             }
197         } else if (artifact instanceof ArtifactWithDependencies) {
198             pomArtifact = artifact;
199 
200             dependencies = ((ArtifactWithDependencies) artifact).getDependencies();
201 
202             managedDependencies = ((ArtifactWithDependencies) artifact).getManagedDependencies();
203         } else {
204             ProjectRelocation rel = retrieveRelocatedProject(artifact, request);
205 
206             if (rel == null) {
207                 return null;
208             }
209 
210             pomArtifact = rel.pomArtifact;
211 
212             relocatedArtifact = rel.relocatedArtifact;
213 
214             if (rel.project == null) {
215                 // When this happens we have a Maven 1.x POM, or some invalid POM.
216                 // It should have never found its way into Maven 2.x repository but it did.
217                 dependencies = Collections.emptyList();
218             } else {
219                 dependencies = rel.project.getDependencies();
220 
221                 DependencyManagement depMgmt = rel.project.getDependencyManagement();
222                 managedDependencies = (depMgmt != null) ? depMgmt.getDependencies() : null;
223 
224                 pomRepositories = rel.project.getRemoteArtifactRepositories();
225             }
226         }
227 
228         Set<Artifact> artifacts = Collections.emptySet();
229 
230         if (!artifact.getArtifactHandler().isIncludesDependencies()) {
231             artifacts = new LinkedHashSet<>();
232 
233             for (Dependency dependency : dependencies) {
234                 Artifact dependencyArtifact = createDependencyArtifact(dependency, artifact, pomArtifact);
235 
236                 if (dependencyArtifact != null) {
237                     artifacts.add(dependencyArtifact);
238                 }
239             }
240         }
241 
242         Map<String, Artifact> managedVersions = null;
243 
244         if (managedDependencies != null && request.isResolveManagedVersions()) {
245             managedVersions = new HashMap<>();
246 
247             for (Dependency managedDependency : managedDependencies) {
248                 Artifact managedArtifact = createDependencyArtifact(managedDependency, null, pomArtifact);
249 
250                 managedVersions.put(managedDependency.getManagementKey(), managedArtifact);
251             }
252         }
253 
254         List<ArtifactRepository> aggregatedRepositories =
255                 aggregateRepositories(request.getRemoteRepositories(), pomRepositories);
256 
257         ResolutionGroup result =
258                 new ResolutionGroup(pomArtifact, relocatedArtifact, artifacts, managedVersions, aggregatedRepositories);
259 
260         cache.put(
261                 artifact,
262                 request.isResolveManagedVersions(),
263                 request.getLocalRepository(),
264                 request.getRemoteRepositories(),
265                 result);
266 
267         return result;
268     }
269 
270     private boolean hasFile(Artifact artifact) {
271         return artifact != null
272                 && artifact.getFile() != null
273                 && artifact.getFile().exists();
274     }
275 
276     private List<ArtifactRepository> aggregateRepositories(
277             List<ArtifactRepository> requestRepositories, List<ArtifactRepository> pomRepositories) {
278         List<ArtifactRepository> repositories = requestRepositories;
279 
280         if (pomRepositories != null && !pomRepositories.isEmpty()) {
281             Map<String, ArtifactRepository> repos = new LinkedHashMap<>();
282 
283             for (ArtifactRepository repo : requestRepositories) {
284                 if (!repos.containsKey(repo.getId())) {
285                     repos.put(repo.getId(), repo);
286                 }
287             }
288 
289             for (ArtifactRepository repo : pomRepositories) {
290                 if (!repos.containsKey(repo.getId())) {
291                     repos.put(repo.getId(), repo);
292                 }
293             }
294 
295             repositories = new ArrayList<>(repos.values());
296         }
297 
298         return repositories;
299     }
300 
301     private Artifact createDependencyArtifact(Dependency dependency, Artifact owner, Artifact pom)
302             throws ArtifactMetadataRetrievalException {
303         try {
304             String inheritedScope = (owner != null) ? owner.getScope() : null;
305 
306             ArtifactFilter inheritedFilter = (owner != null) ? owner.getDependencyFilter() : null;
307 
308             return createDependencyArtifact(repositorySystem, dependency, inheritedScope, inheritedFilter);
309         } catch (InvalidVersionSpecificationException e) {
310             throw new ArtifactMetadataRetrievalException(
311                     "Invalid version for dependency " + dependency.getManagementKey() + ": " + e.getMessage(), e, pom);
312         }
313     }
314 
315     private static Artifact createDependencyArtifact(
316             ArtifactFactory factory, Dependency dependency, String inheritedScope, ArtifactFilter inheritedFilter)
317             throws InvalidVersionSpecificationException {
318         String effectiveScope = getEffectiveScope(dependency.getScope(), inheritedScope);
319 
320         if (effectiveScope == null) {
321             return null;
322         }
323 
324         VersionRange versionRange = VersionRange.createFromVersionSpec(dependency.getVersion());
325 
326         Artifact dependencyArtifact = factory.createDependencyArtifact(
327                 dependency.getGroupId(),
328                 dependency.getArtifactId(),
329                 versionRange,
330                 dependency.getType(),
331                 dependency.getClassifier(),
332                 effectiveScope,
333                 dependency.isOptional());
334 
335         ArtifactFilter dependencyFilter = inheritedFilter;
336 
337         if (dependencyFilter != null && !dependencyFilter.include(dependencyArtifact)) {
338             return null;
339         }
340 
341         if (Artifact.SCOPE_SYSTEM.equals(effectiveScope)) {
342             dependencyArtifact.setFile(new File(dependency.getSystemPath()));
343         }
344 
345         dependencyArtifact.setDependencyFilter(createDependencyFilter(dependency, dependencyFilter));
346 
347         return dependencyArtifact;
348     }
349 
350     private static String getEffectiveScope(String originalScope, String inheritedScope) {
351         String effectiveScope = Artifact.SCOPE_RUNTIME;
352 
353         if (originalScope == null) {
354             originalScope = Artifact.SCOPE_COMPILE;
355         }
356 
357         if (inheritedScope == null) {
358             // direct dependency retains its scope
359             effectiveScope = originalScope;
360         } else if (Artifact.SCOPE_TEST.equals(originalScope) || Artifact.SCOPE_PROVIDED.equals(originalScope)) {
361             // test and provided are not transitive, so exclude them
362             effectiveScope = null;
363         } else if (Artifact.SCOPE_SYSTEM.equals(originalScope)) {
364             // system scope come through unchanged...
365             effectiveScope = Artifact.SCOPE_SYSTEM;
366         } else if (Artifact.SCOPE_COMPILE.equals(originalScope) && Artifact.SCOPE_COMPILE.equals(inheritedScope)) {
367             // added to retain compile scope. Remove if you want compile inherited as runtime
368             effectiveScope = Artifact.SCOPE_COMPILE;
369         } else if (Artifact.SCOPE_TEST.equals(inheritedScope)) {
370             effectiveScope = Artifact.SCOPE_TEST;
371         } else if (Artifact.SCOPE_PROVIDED.equals(inheritedScope)) {
372             effectiveScope = Artifact.SCOPE_PROVIDED;
373         }
374 
375         return effectiveScope;
376     }
377 
378     private static ArtifactFilter createDependencyFilter(Dependency dependency, ArtifactFilter inheritedFilter) {
379         ArtifactFilter effectiveFilter = inheritedFilter;
380 
381         if (!dependency.getExclusions().isEmpty()) {
382             effectiveFilter = new ExclusionArtifactFilter(dependency.getExclusions());
383 
384             if (inheritedFilter != null) {
385                 effectiveFilter = new AndArtifactFilter(Arrays.asList(inheritedFilter, effectiveFilter));
386             }
387         }
388 
389         return effectiveFilter;
390     }
391 
392     public List<ArtifactVersion> retrieveAvailableVersions(
393             Artifact artifact, ArtifactRepository localRepository, List<ArtifactRepository> remoteRepositories)
394             throws ArtifactMetadataRetrievalException {
395         MetadataResolutionRequest request = new DefaultMetadataResolutionRequest();
396         injectSession(request);
397         request.setArtifact(artifact);
398         request.setLocalRepository(localRepository);
399         request.setRemoteRepositories(remoteRepositories);
400         return retrieveAvailableVersions(request);
401     }
402 
403     public List<ArtifactVersion> retrieveAvailableVersions(MetadataResolutionRequest request)
404             throws ArtifactMetadataRetrievalException {
405         RepositoryMetadata metadata = new ArtifactRepositoryMetadata(request.getArtifact());
406 
407         try {
408             repositoryMetadataManager.resolve(metadata, request);
409         } catch (RepositoryMetadataResolutionException e) {
410             throw new ArtifactMetadataRetrievalException(e.getMessage(), e, request.getArtifact());
411         }
412 
413         List<String> availableVersions = request.getLocalRepository().findVersions(request.getArtifact());
414 
415         return retrieveAvailableVersionsFromMetadata(metadata.getMetadata(), availableVersions);
416     }
417 
418     public List<ArtifactVersion> retrieveAvailableVersionsFromDeploymentRepository(
419             Artifact artifact, ArtifactRepository localRepository, ArtifactRepository deploymentRepository)
420             throws ArtifactMetadataRetrievalException {
421         RepositoryMetadata metadata = new ArtifactRepositoryMetadata(artifact);
422 
423         try {
424             repositoryMetadataManager.resolveAlways(metadata, localRepository, deploymentRepository);
425         } catch (RepositoryMetadataResolutionException e) {
426             throw new ArtifactMetadataRetrievalException(e.getMessage(), e, artifact);
427         }
428 
429         List<String> availableVersions = localRepository.findVersions(artifact);
430 
431         return retrieveAvailableVersionsFromMetadata(metadata.getMetadata(), availableVersions);
432     }
433 
434     private List<ArtifactVersion> retrieveAvailableVersionsFromMetadata(
435             Metadata repoMetadata, List<String> availableVersions) {
436         Collection<String> versions = new LinkedHashSet<>();
437 
438         if ((repoMetadata != null) && (repoMetadata.getVersioning() != null)) {
439             versions.addAll(repoMetadata.getVersioning().getVersions());
440         }
441 
442         versions.addAll(availableVersions);
443 
444         List<ArtifactVersion> artifactVersions = new ArrayList<>(versions.size());
445 
446         for (String version : versions) {
447             artifactVersions.add(new DefaultArtifactVersion(version));
448         }
449 
450         return artifactVersions;
451     }
452 
453     // USED BY MAVEN ASSEMBLY PLUGIN
454     @Deprecated
455     public static Set<Artifact> createArtifacts(
456             ArtifactFactory artifactFactory,
457             List<Dependency> dependencies,
458             String inheritedScope,
459             ArtifactFilter dependencyFilter,
460             MavenProject project)
461             throws InvalidDependencyVersionException {
462         Set<Artifact> artifacts = new LinkedHashSet<>();
463 
464         for (Dependency d : dependencies) {
465             Artifact dependencyArtifact;
466             try {
467                 dependencyArtifact = createDependencyArtifact(artifactFactory, d, inheritedScope, dependencyFilter);
468             } catch (InvalidVersionSpecificationException e) {
469                 throw new InvalidDependencyVersionException(project.getId(), d, project.getFile(), e);
470             }
471 
472             if (dependencyArtifact != null) {
473                 artifacts.add(dependencyArtifact);
474             }
475         }
476 
477         return artifacts;
478     }
479 
480     private ProjectBuilder getProjectBuilder() {
481         if (projectBuilder != null) {
482             return projectBuilder;
483         }
484 
485         try {
486             projectBuilder = container.lookup(ProjectBuilder.class);
487         } catch (ComponentLookupException e) {
488             // Won't happen
489         }
490 
491         return projectBuilder;
492     }
493 
494     @SuppressWarnings("checkstyle:methodlength")
495     private ProjectRelocation retrieveRelocatedProject(Artifact artifact, MetadataResolutionRequest repositoryRequest)
496             throws ArtifactMetadataRetrievalException {
497         MavenProject project;
498 
499         Artifact pomArtifact;
500         Artifact relocatedArtifact = null;
501         boolean done = false;
502         do {
503             project = null;
504 
505             pomArtifact = repositorySystem.createProjectArtifact(
506                     artifact.getGroupId(), artifact.getArtifactId(), artifact.getVersion(), artifact.getScope());
507 
508             if ("pom".equals(artifact.getType())) {
509                 pomArtifact.setFile(artifact.getFile());
510             }
511 
512             if (Artifact.SCOPE_SYSTEM.equals(artifact.getScope())) {
513                 done = true;
514             } else {
515                 try {
516                     ProjectBuildingRequest configuration = new DefaultProjectBuildingRequest();
517                     configuration.setLocalRepository(repositoryRequest.getLocalRepository());
518                     configuration.setRemoteRepositories(repositoryRequest.getRemoteRepositories());
519                     configuration.setValidationLevel(ModelBuildingRequest.VALIDATION_LEVEL_MINIMAL);
520                     configuration.setProcessPlugins(false);
521                     configuration.setRepositoryMerging(ProjectBuildingRequest.RepositoryMerging.REQUEST_DOMINANT);
522                     MavenSession session = legacySupport.getSession();
523                     if (session != null) {
524                         configuration.setSystemProperties(session.getSystemProperties());
525                         configuration.setUserProperties(session.getUserProperties());
526                     } else {
527                         configuration.setSystemProperties(getSystemProperties());
528                         configuration.setUserProperties(new Properties());
529                     }
530                     configuration.setRepositorySession(legacySupport.getRepositorySession());
531 
532                     project = getProjectBuilder()
533                             .build(pomArtifact, configuration)
534                             .getProject();
535                 } catch (ProjectBuildingException e) {
536                     ModelProblem missingParentPom = hasMissingParentPom(e);
537                     if (missingParentPom != null) {
538                         throw new ArtifactMetadataRetrievalException(
539                                 "Failed to process POM for " + artifact.getId() + ": " + missingParentPom.getMessage(),
540                                 missingParentPom.getException(),
541                                 artifact);
542                     }
543 
544                     String message;
545 
546                     if (isMissingPom(e)) {
547                         message = "Missing POM for " + artifact.getId();
548                     } else if (isNonTransferrablePom(e)) {
549                         throw new ArtifactMetadataRetrievalException(
550                                 "Failed to retrieve POM for " + artifact.getId() + ": "
551                                         + e.getCause().getMessage(),
552                                 e.getCause(),
553                                 artifact);
554                     } else {
555                         message = "Invalid POM for " + artifact.getId()
556                                 + ", transitive dependencies (if any) will not be available"
557                                 + ", enable debug logging for more details";
558                     }
559 
560                     if (logger.isDebugEnabled()) {
561                         message += ": " + e.getMessage();
562                     }
563 
564                     logger.warn(message);
565                 }
566 
567                 if (project != null) {
568                     Relocation relocation = null;
569 
570                     DistributionManagement distMgmt = project.getDistributionManagement();
571                     if (distMgmt != null) {
572                         relocation = distMgmt.getRelocation();
573 
574                         artifact.setDownloadUrl(distMgmt.getDownloadUrl());
575                         pomArtifact.setDownloadUrl(distMgmt.getDownloadUrl());
576                     }
577 
578                     if (relocation != null) {
579                         if (relocation.getGroupId() != null) {
580                             artifact.setGroupId(relocation.getGroupId());
581                             relocatedArtifact = artifact;
582                             project.setGroupId(relocation.getGroupId());
583                         }
584                         if (relocation.getArtifactId() != null) {
585                             artifact.setArtifactId(relocation.getArtifactId());
586                             relocatedArtifact = artifact;
587                             project.setArtifactId(relocation.getArtifactId());
588                         }
589                         if (relocation.getVersion() != null) {
590                             // note: see MNG-3454. This causes a problem, but fixing it may break more.
591                             artifact.setVersionRange(VersionRange.createFromVersion(relocation.getVersion()));
592                             relocatedArtifact = artifact;
593                             project.setVersion(relocation.getVersion());
594                         }
595 
596                         if (artifact.getDependencyFilter() != null
597                                 && !artifact.getDependencyFilter().include(artifact)) {
598                             return null;
599                         }
600 
601                         // MNG-2861: the artifact data has changed. If the available versions where previously
602                         // retrieved, we need to update it.
603                         // TODO shouldn't the versions be merged across relocations?
604                         List<ArtifactVersion> available = artifact.getAvailableVersions();
605                         if (available != null && !available.isEmpty()) {
606                             MetadataResolutionRequest metadataRequest =
607                                     new DefaultMetadataResolutionRequest(repositoryRequest);
608                             metadataRequest.setArtifact(artifact);
609                             available = retrieveAvailableVersions(metadataRequest);
610                             artifact.setAvailableVersions(available);
611                         }
612 
613                         String message = "\n  This artifact has been relocated to " + artifact.getGroupId() + ":"
614                                 + artifact.getArtifactId() + ":" + artifact.getVersion() + ".\n";
615 
616                         if (relocation.getMessage() != null) {
617                             message += "  " + relocation.getMessage() + "\n";
618                         }
619 
620                         if (artifact.getDependencyTrail() != null
621                                 && artifact.getDependencyTrail().size() == 1) {
622                             logger.warn("While downloading " + pomArtifact.getGroupId() + ":"
623                                     + pomArtifact.getArtifactId() + ":" + pomArtifact.getVersion() + message + "\n");
624                         } else {
625                             logger.debug("While downloading " + pomArtifact.getGroupId() + ":"
626                                     + pomArtifact.getArtifactId() + ":" + pomArtifact.getVersion() + message + "\n");
627                         }
628                     } else {
629                         done = true;
630                     }
631                 } else {
632                     done = true;
633                 }
634             }
635         } while (!done);
636 
637         ProjectRelocation rel = new ProjectRelocation();
638         rel.project = project;
639         rel.pomArtifact = pomArtifact;
640         rel.relocatedArtifact = relocatedArtifact;
641 
642         return rel;
643     }
644 
645     private ModelProblem hasMissingParentPom(ProjectBuildingException e) {
646         if (e.getCause() instanceof ModelBuildingException) {
647             ModelBuildingException mbe = (ModelBuildingException) e.getCause();
648             for (ModelProblem problem : mbe.getProblems()) {
649                 if (problem.getException() instanceof UnresolvableModelException) {
650                     return problem;
651                 }
652             }
653         }
654         return null;
655     }
656 
657     private boolean isMissingPom(Exception e) {
658         if (e.getCause() instanceof MultipleArtifactsNotFoundException) {
659             return true;
660         }
661         return e.getCause() instanceof org.eclipse.aether.resolution.ArtifactResolutionException
662                 && e.getCause().getCause() instanceof ArtifactNotFoundException;
663     }
664 
665     private boolean isNonTransferrablePom(Exception e) {
666         if (e.getCause() instanceof ArtifactResolutionException) {
667             return true;
668         }
669         return e.getCause() instanceof org.eclipse.aether.resolution.ArtifactResolutionException
670                 && !(e.getCause().getCause() instanceof ArtifactNotFoundException);
671     }
672 
673     private Properties getSystemProperties() {
674         Properties props = new Properties();
675 
676         EnvironmentUtils.addEnvVars(props);
677 
678         SystemProperties.addSystemProperties(props);
679 
680         return props;
681     }
682 
683     private static final class ProjectRelocation {
684         private MavenProject project;
685 
686         private Artifact pomArtifact;
687 
688         private Artifact relocatedArtifact;
689     }
690 }