private ProjectVersionRefLocation resolveLatestMultiRefWithLocation(
final List<? extends Location> locations,
final ProjectVersionRef ref,
final VersionSelectionStrategy selectionStrategy,
final EventMetadata eventMetadata)
throws TransferException {
final Map<SingleVersion, Location> available = new TreeMap<SingleVersion, Location>();
for (final Location location : locations) {
try {
final MavenMetadataView metadata =
metadataReader.getMetadata(
ref.asProjectRef(), Collections.singletonList(location), eventMetadata);
if (metadata != null) {
final List<String> versions =
metadata.resolveValues("/metadata/versioning/versions/version");
if (versions != null) {
for (final String version : versions) {
try {
final SingleVersion spec = VersionUtils.createSingleVersion(version);
if (!available.containsKey(spec)) {
available.put(spec, location);
}
} catch (final InvalidVersionSpecificationException e) {
debug(
"Unparsable version spec found in metadata: '%s' for: %s from: %s.",
e, version, ref, location);
}
}
}
}
} catch (final GalleyMavenException e) {
debug(
"Failed to resolve/parse metadata for variable version of: '%s' from: %s.",
e, ref, location);
}
}
if (!available.isEmpty()) {
final VersionSpec spec = ref.getVersionSpec();
final List<SingleVersion> versions = new ArrayList<SingleVersion>(available.keySet());
Collections.sort(versions);
while (!versions.isEmpty()) {
final SingleVersion selected = selectionStrategy.select(versions);
if (selected == null) {
return null;
}
versions.remove(selected);
if (selected.isConcrete() && spec.contains(selected)) {
return new ProjectVersionRefLocation(
ref.selectVersion(selected), available.get(selected));
}
}
}
return null;
}