- (NJMapping *)objectAtIndexedSubscript:(NSUInteger)idx;
- (void)addMappingWithContentsOfURL:(NSURL *)url;
- (void)activateMapping:(NJMapping *)mapping;
- (NJMapping *)objectAtIndexedSubscript:(NSUInteger)idx;
- (void)addMappingWithContentsOfURL:(NSURL *)url;
- (void)activateMapping:(NJMapping *)mapping;