SitemapGen4j is a Java library to generate XML sitemaps. It supports gzipped output, sitemap validation, and sitemap index generation. It can also generate Google-specific sitemaps, such as Mobile sitemaps, Geo sitemaps, Code Search sitemaps, Google News sitemaps, and Video sitemaps.
Redland is a set of C libraries providing a high-level API for the Resource Description Framework (RDF), allowing it to be stored, parsed, serialized, queried, and manipulated. It has an object-based, modular design and comes with detailed reference documentation and examples. Redland supports all RDF vocabularies such as FOAF, RSS 1.0, Dublin Core, DOAP, and OWL, the query languages SPARQL and RDQL, and all RDF syntaxes including Turtle, RDF/XML, RDF/JSON, RSS, Atom, RDFa, and GRDDL.