Introduce two exceptions to distinquish between resolution failures

core/src/main/java/org/wildfly/channel/ArtifactTransferException.java

@@ -0,0 +1,20 @@
+package org.wildfly.channel;
+
+import java.util.Set;
+
+/**
+ * Thrown in case of an error during downloading of one or more of required artifacts.
+ */
+public class ArtifactTransferException extends UnresolvedMavenArtifactException {
+
+    public ArtifactTransferException(String localizedMessage,
+                                    Throwable cause,
+                                    Set<ArtifactCoordinate> unresolvedArtifacts,
+                                    Set<Repository> attemptedRepositories) {
+        super(localizedMessage, cause, unresolvedArtifacts, attemptedRepositories);
+    }
+
+    public ArtifactTransferException(String message, Set<ArtifactCoordinate> unresolvedArtifacts, Set<Repository> attemptedRepositories) {
+        super(message, unresolvedArtifacts, attemptedRepositories);
+    }
+}

core/src/main/java/org/wildfly/channel/ChannelSession.java

@@ -105,10 +105,12 @@ public ChannelSession(List<Channel> channelDefinitions, MavenVersionsResolver.Fa
      * @param baseVersion - can be null. The base version is required when the stream for the component specifies multiple versions and needs the base version to
      *                    determine the appropriate version to resolve.
      * @return the Maven Artifact (with a file corresponding to the artifact).
-     * @throws UnresolvedMavenArtifactException if the latest version can not be resolved or the artifact itself can not be resolved.
+     * @throws NoStreamFoundException if none of the channels in the {@code ChannelSession} provides the artifact
+     * @throws ArtifactTransferException if the artifact is provided by the {@code ChannelSession}, but the resolution failed
      *
      */
-    public MavenArtifact resolveMavenArtifact(String groupId, String artifactId, String extension, String classifier, String baseVersion) throws UnresolvedMavenArtifactException {
+    public MavenArtifact resolveMavenArtifact(String groupId, String artifactId, String extension, String classifier, String baseVersion)
+            throws NoStreamFoundException, ArtifactTransferException {
         requireNonNull(groupId);
         requireNonNull(artifactId);
         // baseVersion is not used at the moment but will provide essential to support advanced use cases to determine multiple streams of the same Maven component.
@@ -134,7 +136,8 @@ public MavenArtifact resolveMavenArtifact(String groupId, String artifactId, Str
      *
      * @param coordinates list of ArtifactCoordinates to resolve
      * @return a list of resolved MavenArtifacts with resolved versions asnd files
-     * @throws UnresolvedMavenArtifactException
+     * @throws NoStreamFoundException if one or more of the artifact is not provided by any of the channels in the {@code ChannelSession}
+     * @throws ArtifactTransferException if one or more of the artifacts is provided by the {@code ChannelSession}, but the resolution failed
      */
     public List<MavenArtifact> resolveMavenArtifacts(List<ArtifactCoordinate> coordinates) throws UnresolvedMavenArtifactException {
         requireNonNull(coordinates);
@@ -167,9 +170,9 @@ public List<MavenArtifact> resolveMavenArtifacts(List<ArtifactCoordinate> coordi
      * @param classifier - can be null
      * @param version - required
      * @return the Maven Artifact (with a file corresponding to the artifact).
-     * @throws UnresolvedMavenArtifactException if the artifact can not be resolved
+     * @throws ArtifactTransferException if the artifact can not be resolved
      */
-    public MavenArtifact resolveDirectMavenArtifact(String groupId, String artifactId, String extension, String classifier, String version) throws UnresolvedMavenArtifactException {
+    public MavenArtifact resolveDirectMavenArtifact(String groupId, String artifactId, String extension, String classifier, String version) throws ArtifactTransferException {
         requireNonNull(groupId);
         requireNonNull(artifactId);
         requireNonNull(version);
@@ -186,9 +189,9 @@ public MavenArtifact resolveDirectMavenArtifact(String groupId, String artifactI
      *
      * @param coordinates - list of ArtifactCoordinates to check
      * @return the Maven Artifact (with a file corresponding to the artifact).
-     * @throws UnresolvedMavenArtifactException if the artifact can not be resolved
+     * @throws ArtifactTransferException if the artifact can not be resolved
      */
-    public List<MavenArtifact> resolveDirectMavenArtifacts(List<ArtifactCoordinate> coordinates) throws UnresolvedMavenArtifactException {
+    public List<MavenArtifact> resolveDirectMavenArtifacts(List<ArtifactCoordinate> coordinates) throws ArtifactTransferException {
         coordinates.forEach(c -> {
             requireNonNull(c.getGroupId());
             requireNonNull(c.getArtifactId());
@@ -217,9 +220,9 @@ public List<MavenArtifact> resolveDirectMavenArtifacts(List<ArtifactCoordinate>
      * @param baseVersion - can be null. The base version is required when the stream for the component specifies multiple versions and needs the base version to
      *                    determine the appropriate version to resolve.
      * @return the latest version if a Maven artifact
-     * @throws UnresolvedMavenArtifactException if the latest version cannot be established
+     * @throws NoStreamFoundException if the latest version cannot be established
      */
-    public String findLatestMavenArtifactVersion(String groupId, String artifactId, String extension, String classifier, String baseVersion) throws UnresolvedMavenArtifactException {
+    public String findLatestMavenArtifactVersion(String groupId, String artifactId, String extension, String classifier, String baseVersion) throws NoStreamFoundException {
         return findChannelWithLatestVersion(groupId, artifactId, extension, classifier, baseVersion).version;
     }
 
@@ -250,7 +253,7 @@ private void validateNoDuplicatedManifests() {
         }
     }
 
-    private ChannelImpl.ResolveLatestVersionResult findChannelWithLatestVersion(String groupId, String artifactId, String extension, String classifier, String baseVersion) throws UnresolvedMavenArtifactException {
+    private ChannelImpl.ResolveLatestVersionResult findChannelWithLatestVersion(String groupId, String artifactId, String extension, String classifier, String baseVersion) throws NoStreamFoundException {
         requireNonNull(groupId);
         requireNonNull(artifactId);
 
@@ -270,7 +273,7 @@ private ChannelImpl.ResolveLatestVersionResult findChannelWithLatestVersion(Stri
                     .map(ChannelImpl::getChannelDefinition)
                     .flatMap(d -> d.getRepositories().stream())
                     .collect(Collectors.toSet());
-            throw new UnresolvedMavenArtifactException(
+            throw new NoStreamFoundException(
                     String.format("Can not resolve latest Maven artifact (no stream found) : %s:%s:%s:%s", groupId, artifactId, extension, classifier),
                     Collections.singleton(coord), repositories);
         }));

core/src/main/java/org/wildfly/channel/NoStreamFoundException.java

@@ -0,0 +1,20 @@
+package org.wildfly.channel;
+
+import java.util.Set;
+
+/**
+ * Thrown if one or more of required artifacts are not found in specified Channels
+ */
+public class NoStreamFoundException extends UnresolvedMavenArtifactException {
+
+    public NoStreamFoundException(String localizedMessage,
+                                  Throwable cause,
+                                  Set<ArtifactCoordinate> unresolvedArtifacts,
+                                  Set<Repository> attemptedRepositories) {
+        super(localizedMessage, cause, unresolvedArtifacts, attemptedRepositories);
+    }
+
+    public NoStreamFoundException(String message, Set<ArtifactCoordinate> unresolvedArtifacts, Set<Repository> attemptedRepositories) {
+        super(message, unresolvedArtifacts, attemptedRepositories);
+    }
+}

core/src/main/java/org/wildfly/channel/UnresolvedMavenArtifactException.java

@@ -18,7 +18,7 @@
 
 import java.util.Set;
 
-public class UnresolvedMavenArtifactException extends RuntimeException {
+public abstract class UnresolvedMavenArtifactException extends RuntimeException {
 
     private final Set<ArtifactCoordinate> unresolvedArtifacts;
     private final Set<Repository> attemptedRepositories;
@@ -32,7 +32,7 @@ public UnresolvedMavenArtifactException(String localizedMessage,
         this.attemptedRepositories = attemptedRepositories;
     }
 
-    public <E> UnresolvedMavenArtifactException(String message, Set<ArtifactCoordinate> unresolvedArtifacts, Set<Repository> attemptedRepositories) {
+    public UnresolvedMavenArtifactException(String message, Set<ArtifactCoordinate> unresolvedArtifacts, Set<Repository> attemptedRepositories) {
         super(message);
         this.unresolvedArtifacts = unresolvedArtifacts;
         this.attemptedRepositories = attemptedRepositories;

core/src/main/java/org/wildfly/channel/spi/MavenVersionsResolver.java

@@ -24,6 +24,7 @@
 import java.util.Set;
 
 import org.wildfly.channel.ArtifactCoordinate;
+import org.wildfly.channel.ArtifactTransferException;
 import org.wildfly.channel.ChannelMetadataCoordinate;
 import org.wildfly.channel.Repository;
 import org.wildfly.channel.UnresolvedMavenArtifactException;
@@ -57,9 +58,9 @@ public interface MavenVersionsResolver extends Closeable {
     *
     * @return a File representing the resolved Maven artifact.
     *
-    * @throws UnresolvedMavenArtifactException if the artifact can not be resolved.
+    * @throws ArtifactTransferException if the artifact can not be resolved.
     */
-   File resolveArtifact(String groupId, String artifactId, String extension, String classifier, String version) throws UnresolvedMavenArtifactException;
+   File resolveArtifact(String groupId, String artifactId, String extension, String classifier, String version) throws ArtifactTransferException;
 
    /**
     * Resolve a list of maven artifacts based on the full coordinates.
@@ -70,9 +71,9 @@ public interface MavenVersionsResolver extends Closeable {
     *
     * @return a list of File representing the resolved Maven artifact.
     *
-    * @throws UnresolvedMavenArtifactException if any artifacts can not be resolved.
+    * @throws ArtifactTransferException if any artifacts can not be resolved.
     */
-   List<File> resolveArtifacts(List<ArtifactCoordinate> coordinates) throws UnresolvedMavenArtifactException;
+   List<File> resolveArtifacts(List<ArtifactCoordinate> coordinates) throws ArtifactTransferException;
 
    /**
     * Resolve a list of channel metadata artifacts based on the coordinates.
@@ -88,9 +89,9 @@ public interface MavenVersionsResolver extends Closeable {
     *
     * @return a list of URLs to the metadata files
     *
-    * @throws UnresolvedMavenArtifactException if any artifacts can not be resolved.
+    * @throws ArtifactTransferException if any artifacts can not be resolved.
     */
-   List<URL> resolveChannelMetadata(List<? extends ChannelMetadataCoordinate> manifestCoords) throws UnresolvedMavenArtifactException;
+   List<URL> resolveChannelMetadata(List<? extends ChannelMetadataCoordinate> manifestCoords) throws ArtifactTransferException;
 
    /**
     * Returns the {@code <release>} version according to the repositories' Maven metadata. If multiple repositories

core/src/test/java/org/wildfly/channel/ChannelSessionInitTestCase.java

@@ -122,7 +122,7 @@ public void throwExceptionRequiredChannelIdNotAvailableAndNotAbleToResolve() thr
         mockManifest(resolver, baseManifest, "test.channels:base-manifest:1.0.0");
 
         when(resolver.resolveChannelMetadata(List.of(new ChannelManifestCoordinate("test.channels", "i-dont-exist", "1.0.0"))))
-                .thenThrow(UnresolvedMavenArtifactException.class);
+                .thenThrow(ArtifactTransferException.class);
 
         List<Channel> channels = List.of(new Channel.Builder()
                         .setName("root level requiring channel")

maven-resolver/src/main/java/org/wildfly/channel/maven/VersionResolverFactory.java

@@ -56,10 +56,12 @@
 import org.eclipse.aether.resolution.VersionRangeResult;
 import org.eclipse.aether.version.Version;
 import org.wildfly.channel.ArtifactCoordinate;
+import org.wildfly.channel.ArtifactTransferException;
 import org.wildfly.channel.Channel;
 import org.wildfly.channel.ChannelMapper;
 import org.wildfly.channel.ChannelMetadataCoordinate;
 import org.wildfly.channel.Repository;
+import org.wildfly.channel.NoStreamFoundException;
 import org.wildfly.channel.UnresolvedMavenArtifactException;
 import org.wildfly.channel.spi.MavenVersionsResolver;
 import org.wildfly.channel.version.VersionMatcher;
@@ -150,7 +152,7 @@ public Set<String> getAllVersions(String groupId, String artifactId, String exte
         }
 
         @Override
-        public File resolveArtifact(String groupId, String artifactId, String extension, String classifier, String version) throws UnresolvedMavenArtifactException {
+        public File resolveArtifact(String groupId, String artifactId, String extension, String classifier, String version) throws ArtifactTransferException {
             requireNonNull(groupId);
             requireNonNull(artifactId);
             requireNonNull(version);
@@ -167,7 +169,7 @@ public File resolveArtifact(String groupId, String artifactId, String extension,
             try {
                 result = system.resolveArtifact(session, request);
             } catch (ArtifactResolutionException ex) {
-                throw new UnresolvedMavenArtifactException(ex.getLocalizedMessage(), ex,
+                throw new ArtifactTransferException(ex.getLocalizedMessage(), ex,
                         singleton(new ArtifactCoordinate(groupId, artifactId, extension, classifier, version)),
                         attemptedRepositories());
             }
@@ -203,12 +205,12 @@ public List<File> resolveArtifacts(List<ArtifactCoordinate> coordinates) throws
                    .map(res->res.getRequest().getArtifact())
                    .map(a->new ArtifactCoordinate(a.getGroupId(), a.getArtifactId(), a.getExtension(), a.getClassifier(), a.getVersion()))
                    .collect(Collectors.toSet());
-                throw new UnresolvedMavenArtifactException(ex.getLocalizedMessage(), ex, failed, attemptedRepositories());
+                throw new ArtifactTransferException(ex.getLocalizedMessage(), ex, failed, attemptedRepositories());
             }
         }
 
         @Override
-        public List<URL> resolveChannelMetadata(List<? extends ChannelMetadataCoordinate> coords) throws UnresolvedMavenArtifactException {
+        public List<URL> resolveChannelMetadata(List<? extends ChannelMetadataCoordinate> coords) throws ArtifactTransferException {
             requireNonNull(coords);
 
             List<URL> channels = new ArrayList<>();
@@ -225,7 +227,7 @@ public List<URL> resolveChannelMetadata(List<? extends ChannelMetadataCoordinate
                     Set<String> versions = getAllVersions(coord.getGroupId(), coord.getArtifactId(), coord.getExtension(), coord.getClassifier());
                     Optional<String> latestVersion = VersionMatcher.getLatestVersion(versions);
                     version = latestVersion.orElseThrow(() ->
-                        new UnresolvedMavenArtifactException(String.format("Unable to resolve the latest version of channel metadata %s:%s", coord.getGroupId(), coord.getArtifactId()),
+                        new ArtifactTransferException(String.format("Unable to resolve the latest version of channel metadata %s:%s", coord.getGroupId(), coord.getArtifactId()),
                                 singleton(new ArtifactCoordinate(coord.getGroupId(), coord.getArtifactId(), coord.getExtension(), coord.getClassifier(), "")),
                                 attemptedRepositories()));
                 }
@@ -234,7 +236,7 @@ public List<URL> resolveChannelMetadata(List<? extends ChannelMetadataCoordinate
                 try {
                     channels.add(channelArtifact.toURI().toURL());
                 } catch (MalformedURLException e) {
-                    throw new UnresolvedMavenArtifactException(String.format("Unable to resolve the latest version of channel metadata %s:%s", coord.getGroupId(), coord.getArtifactId()), e,
+                    throw new ArtifactTransferException(String.format("Unable to resolve the latest version of channel metadata %s:%s", coord.getGroupId(), coord.getArtifactId()), e,
                             singleton(new ArtifactCoordinate(coord.getGroupId(), coord.getArtifactId(),
                                     coord.getExtension(), coord.getClassifier(), coord.getVersion())),
                             attemptedRepositories());
@@ -276,15 +278,15 @@ private String findLatestMetadataVersion(List<MetadataResult> metadataResults,
                             return reader.read(new FileReader(f));
                         } catch (IOException | XmlPullParserException e) {
                             final ArtifactCoordinate requestedArtifact = new ArtifactCoordinate(groupId, artifactId, null, null, "*");
-                            throw new UnresolvedMavenArtifactException(e.getLocalizedMessage(), e, singleton(requestedArtifact),
+                            throw new ArtifactTransferException(e.getLocalizedMessage(), e, singleton(requestedArtifact),
                                     attemptedRepositories());
                         }
                     })
                     .filter(m->m.getVersioning() != null)
                     .map(getVersion)
                     .filter(s->s!=null&&!s.isEmpty())
                     .max(COMPARATOR)
-                    .orElseThrow(()-> new UnresolvedMavenArtifactException("No versioning information found in metadata.",
+                    .orElseThrow(()-> new NoStreamFoundException("No versioning information found in metadata.",
                         singleton(new ArtifactCoordinate(groupId, artifactId, null, null, "*")),
                             attemptedRepositories()));
         }