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- readVersions() it receives a version quiery and interprets it depending on the repository (metadata for remote) contents. It is the only API that deals with version ranges and special suffixes like LATEST or SNAPSHOT, all other APIs accept version literally and don't try to interpret it
- readDependencies() - based on the artifact coordinates and environment (passed as Hashtable) returns artifact dependencies. It actually calls out to DependencyProcessor implementation to interpret POM files, thus is just a thin layer that interprets what DependencyProcessor digested and spit back. It repo reader also provides a readMetadata() callback so that DependencyProcessor can access all the metadata it needs
- readArtifacts() is the simplest of them - just reads artifacts based on supplied coordinates. It can also use results of previous calls to readVersions() because the latter transiently records the repository where a version was found.
RepositoryWriter API explanation
RepositoryWriter is a primitive writeArtifacts() implementation. Due to intimate relationship with JettyTransport, implementation of this API call in remote-repository-m2 is also transactional; it ensures all-or-nothing deployment.
Artifact versions special treatment
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