code: public static @Extension ContentMappings newInstance() throws IOException {
          ContentMappings mappings = Persistence.load(ContentMappings.class);
          if (mappings == null) {
              mappings = (ContentMappings) new XmlProxy().readResolve();
          }
          return mappings;
      }
docs: Constructs a new ContentMappings using an existing config file or default settings if not found.